Ento Ento6331 331 331

Pests of Crops and their Management–ENTO-331 (3+1) – Revised Syllabus Dr. Cherukuri Sreenivasa Rao Associate Professor & Head, Department of Entomology, Agricultural College, JAGTIAL

EntoEnto-331 Pests of Crops & their Management

Prepared by Dr. Cherukuri Sreenivasa Rao M.Sc.(Ag.), Ph.D.(IARI)

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Associate Professor & Head Department of Entomology Agricultural College Jagtial-505529 Karminagar District


ENTO 331 PESTS OF CROPS & THIER MANAGEMENT Total Number of Theory Classes Total Number of Practical Classes Plan of course outline: Course Number Course Title Credit Hours General Objective

: 48 (48 Hours) : 16 (40 Hours)

: ENTO-331 : Pests of Crops & their Management : 4 (3+1) (Theory+Practicals) : To impart knowledge to the students on the identification and management of pests of different crops. Course In-Charge : Dr. Cherukuri Sreenivasa Rao Associate Professor & Head Department of Entomology Agricultural College, JAGTIAL-505529 Karimanagar District, Andhra Pradesh Academic level of learners at entry : II Year B.Sc.(Ag.) Academic Calendar in which course offered : III Year B.Sc.(Ag.), I Semester Course Objectives: Theory: By the end of the course, the students will be able to (i) know the distribution pattern of insect pests in AP and India, (ii) know the host range of different insect pests, (iii) know the nature and symptoms of different pests, (iv) know the life cycle of major insect pests of different crops, and (v) know the integrated pest management practices of different insect and non-insect pests. Practicals: By the end of practical exercises, the students will be able to (i) identify the insect and non-insect pests, and (ii) diagnose the different insect pests based on symptoms of damage. MARKS Distribution Allotted Marks 60 90 150 15 10 25 20 05 50 200

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Type of Examination Mid-Semester Exam Theory Semester Final Examination Theory-TOTAL Class Work-Practical Record Class Work-Insect Collection Practicals Class Work-TOTAL Final Practical Examination-Written Examination Final Practical Examination-Viva Voce Final Practical Examination-TOTAL TOTAL (Theory+Practicals) (150+50) • Total 200 marks will be reduced to 100 (reduced to 10 for calculation of Grade Point) • Grade Point (GP) in course should be 5.0/10.0 to PASS in the course Points to Remember • Student should get 50% of marks to PASS in Final Theory Examination • Student should get 50% of marks to PASS in Final Practical Examination • Student should get 5.0 GP to PASS in the Course


Theory-Lecture Wise outlines (As per the Green Book of 2010)

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1. Introduction of economic entomology and economic classification of insect pests. 2. Major insect pests of rice-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of yellow stem borer and gall midge. 3. Major insect pests of rice-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of BPH and GLH. 4. Major insect pests of rice-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of hispa, leaf folder and ear head bug. 5. Minor insect pests of rice-nature and symptoms of damage and management strategies and IPM practices for grasshoppers, root weevil, swarming caterpillar, climbing cutworm, caseworm, whorl.maggot, leaf mite and panicle mite. 6. Major insect pests of sorghum and millets-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of sorghum shoot fly, sorghum stem borer, pink borer, sorghum midge and ear head bug. 7. Major insect pests of sorghum-distribution-marks of identification biology-nature and symptoms of damage and management strategies of Red Hairy Caterpillar (RHC). 8. Minor insect pests of sorghum and millets-nature and symptoms of damage and management practices of deccan wingless grasshopper, aphids, maize shoot bug, flea beetle, blister beetle, ragi cut worm, ragi root aphid and army worm; Insect pests of wheat - nature and symptoms of damage and management practices of ghujia weevil, ragi pink borer and termites. 9. Major insect pests of sugarcane-distribution-marks of identification biology-nature and symptoms of damage and management strategies of early shoot borer, inter-nodal borer and top shoot borer. 10. Major insect pests of sugarcane-nature and symptoms of damage and management strategies of scales, leafhoppers and white grubs. 11. Minor insect pests of sugarcane-nature and symptoms of damage and management' practices of mealybug, termites, whiteflies, wooly aphid and yellow mite. 12. Major insect pests of cotton-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of spotted bollworm, pink bollworm, gram caterpillar and tobacco caterpillar. 13. Major insect pests of cotton-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of leafhoppers and whiteflies. 14. Minor insect pests of cotton-nature and symptoms of damage and management strategies at aphids, thrips, red cotton bug, dusky cotton bug, leaf roller, stem weevil, grasshopper and mealybug-IPM practices in cotton. 15. Insect pests of mesta-distribution-marks of identification-biology, nature and symptoms of damage and management strategies of hairy caterpillar and minor insect pests (aphids, semilooper; flea beetle, mealybug and leafhopper); Insect pest of sunhemp-nature and symptoms of damage and management practices of hairy caterpillar and minor pests (stem weevil, stem borer, flea beetle and mealybug). 16. Major insect pests of pulses, beans and peas-distribution-marks of identification-biologynature and symptoms of damage and management strategies of gram caterpillar, plume moth, pod fly, stem fly and spotted pod borer. 17. Minor insect pests of pulses, beans and peas-nature and symptoms of damage and management practices of cowpea aphids, cowbugs, pod bug, leafhopper, stink bug, green pod boring caterpillar and blue butterflies; Insect pests of peas-nature and symptoms of damage and management practices of pea leaf miner and pea stem fly; Insect pests of soybean-nature and symptoms of damage and management practices of stem fly and Spodoptera exigua and minor pest (whiteflies). 18. Major insect pests, of castor-distribution-marks of identification biology-nature and symptoms of damage and management strategies of semilooper, shoot and capsule borer, tobacco caterpillar. Minor insect pests of castor-nature and symptoms of damage and management practices of leafhoppers, butterfly, whitefly, thrips and castor slug.


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19. Major insect pests of groundnut-distribution-marks of identification biology-nature and symptoms of damage and management strategies of white grub, leaf miner, RHC and tobacco caterpillar; Minor insect pests of groundnut-nature and symptoms of damage and management practices of Helicoverpa, leafhoppers, thrips, aphids, pod bugs and jewel beetle. 20. Major insect pests of sesamum-distribution, marks of identification, biology-Nature and symptoms of damage and management strategies of leaf arid pod borer and gall fly; Minor insect pests of sesamum - nature and symptoms of damage and management practices of sphinx caterpillar; Major insect pests of safflower-nature and symptoms of damage and management practices of aphid; Minor pests of safflower-nature and symptoms of damage and management practices of Helicoverpa and Spodoptera exigua. 21. Major insect pests of mustard-distribution-marks of identification biology-nature and symptoms of damage and management strategies of aphids, sawfly and diamondback moth; Minor insect pests of mustard nature and symptoms of damage and management practices of painted bug; Major insect pests of sunflower-distribution-marks of identification-biologynature and symptoms of damage and management strategies of Helicoverpa and Spodoptera; Minor insect pests of sunflower-nature and symptoms of damage and management practices of leafhoppers, bihar hairy caterpillar and thrips. 22. Major insect pests of brinjal-distribution-marks of identification biology-nature and symptoms of damage and management strategies of epilachna beetle, shoot and fruit borer; Minor insect pests of brinjal nature and symptoms of damage and management practices of stem borer, mealybug, aphids, leafhoppers, lacewing bug, leaf webber and red spider mite. 23. Major insect pests of okra-nature and symptoms of damage and management practices of shoot and fruit borer, leafhoppers and white flies; Minor insect pest of okra-nature and symptoms of damage and management practices of spider mite; Major insect pests of tomato-symptoms of damage and management strategies of serpentine leaf miner and fruit borer; Minor insect pests of tomato-symptoms of damage and management strategies of whiteflies. 24. Major insect pests of cucurbits-distribution-marks of identification biology - nature and symptoms of damage and management strategies of fruit flies and pumpkin beetles; Minor insect pests of cucurbitsdistribution-marks of identification-biology-nature and symptoms of damage and management strategies of serpentine leaf miner, semilooper and pumpkin caterpillars; Insect pests of Coccinia-nature and symptoms of damage and management practices of gall fly and aphids. 25. Major insect pests of crucifers-distribution-marks of identification biology-nature and symptoms of damage and management strategies of diamondback moth, cabbage head borer, leaf webber and aphids; Minor insect pests of crucifers-nature and symptoms of damage and management practices and IPM practices of painted bug, tobacco caterpillar and butterflies. 26. Major insect pest of potato and sweet potato-distribution-marks of identification-biologynature and symptoms of damage and management strategies of tuber moth, sweet potato weevil and hairy caterpillar; Minor insect pests of potato and sweet potato - nature and symptoms of damage and management practices of tortoise beetle; Insect pest of moringanature and symptoms of damage and management practices of hairy caterpillar and bud worm. 27. Major insect pests of chillies-distribution-marks of identification biology-nature and symptoms of damage and management strategies of thrips, pod borer, aphids and mites; Minor insect pests of chillies-nature and symptoms of damage and management strategies of blossom midge; Major insects pests of amaranthus-nature and symptoms of damage and management practices of leaf eating caterpillar and stem weevil. 28. Major insect pests of mango-distribution-marks of identification biology-nature and symptoms of damage and management strategies of leafhoppers, stem borer, nut weevil and fruit fly. 29. Minor insect pests of mango-nature and symptoms of damage and management practices of stem borer, mealybug, aphids, leaf webber and red spider mite. 30. Major insect pests of citrus-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of butterfly, fruit sucking moth, citrus leaf miner, psylla and rust mite; Minor insect pests of citrus-nature and symptoms of damage and management practices of bark eating caterpillar, blackfly and leaf mite.


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31. Major insect pests of grapevine-distribution-marks of identification biology-nature and symptoms of damage and management strategies of flea beetles, thrips and mealybug; Minor insect pests-stem girdler, stem borer, Spodoptera, Helicoverpa and root grub and their nature and symptoms of damage and management practices. 32. Major insect pests of cashew-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of tree borer, shoot and blossom webber, tea mosquito bug and thrips; Minor insect pests of cashew - nature and symptoms of damage and management practices of leaf miner. 33. Major insect pests of pomegranate and guava-distribution-marks of identification-biologynature and symptoms of damage and management strategies of butterfly (pomegranate), tea mosquito bug and mealybug (guava); Minor insect pests of pomegranate and guava distribution-marks of identification-biology-nature and symptoms of damage and management strategies of fruit fly and spiraling whitefly. 34. Major insect pests of sapota-distribution-marks of identification biology-nature and symptoms of damage and management strategies of leaf webber; Minor insect pests of sapota-nature and symptoms of damage' and management practices of parijata hairy caterpillar and mealybug; Insect pests of ber-nature and symptoms of damage and management strategies of fruit fly, fruit borer and weevil. 35. Major insect pests of banana-distribution-marks of identification biology-nature and symptoms of damage and management strategies of rhizome weevil; Minor insect pests of banana-nature and symptoms of damage and management strategies of skipper, aphids and pseudo stem weevil; Major insect pests of apple-distribution-marks of identification biologynature and symptoms of damage and management strategies of wooly aphid and codling moth. 36. Major insect pests of coconut-distribution-marks of identification biology-nature and symptoms of damage and management strategies of black headed caterpillar, rhinoceros beetle and red palm weevil; Minor insect pests of coconut-nature and symptoms of damage and management strategies of slug, termites'and mite. 37. Insect pests'of tobacco-distribution-marks of identification-biology nature and symptoms of damage and management strategies of tobacco caterpillar, aphids and whiteflies. 38. Major "insect pest of coffee-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of white borer; Minor insect pests of coffee-nature and symptoms of damage and management strategies of red borer and green scales; Major insect pests of tea-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of tea mosquito bug; Minor pests of tea-nature and symptoms of damage and management strategies of thrips, red spider mite, pink mite, purple mite and scarlet mite. 39. Major insect pests of turmeric and ginger-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of turmeric rhizome, fly; Minor insect pests of turmeric and ginger-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of lacewing bug. 40. Insect pests of betelvine-distribution-marks.of identification-biology nature and symptoms of damage and management strategies of shootbug and Spodoptera. 41. Major insect pest of onion-nature and symptoms of damage and management practices of thrips; Minor insect pest of onion-nature and symptoms of damage and management practices of Spodoptera exigua; Insect pests of coriander-nature and symptoms of damage and management practices of aphids and leaf eating caterpillar. 42. Major insect pests of rose-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of thrips and scales; Minor pests of rose-nature and symptoms of damage and management strategies of leaf eating caterpillar and chaffer beetle; Major insect pests of jasmine-distribution-marks of identification-biology nature and' symptoms of damage and management strategies of stink bugs; Minor insect pests of jasminedistribution-marks of identification-biology-nature and symptoms of damage and management strategies of gall mite; Major insect pests of chrysanthemum-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of aphids.


43. Stored grain pests-biology-preventive and curative measures of rice weevil, lesser grain borer, red flour beetle, khapra beetle, cigarette beetle, pulse beetle and groundnut bruchid. 44. Stored grain pests-biology and preventive and curative measures of saw toothed beetle, rice moth and angoumois grain moth. 45. Locusts-phases (solitary and gregarious)-breeding places-migration, damage and control. 46. Mites-brief morphology and systematics-mites infesting sorghum, cotton, redgram, coconut, vegetables, chillies, citrus and their management practices. 47. Phytoparasitic nematodes-brief morphology and systematics-important phytophagous nematodes in rice (white tip nematode), wheat (cyst and gall nematode), vegetable (root knot nematode), citrus (citrus nematode) and banana (burrowing nematode) and their management. 48. Rodents (infesting field and storage) and birds-nature and symptoms of damage and management of rodents and birds. Practicals: 1. Typical symptoms of damage caused by various phytophagous insects. 2. Identification of major insect pests of paddy and their damage symptoms. 3. Identification of minor insect pests of paddy and their damage symptoms. 4. Identification of insect pests of sorghum, maize and other millets, and their damage symptoms. 5. Identification of insect pests of sugarcane and their damage symptoms. 6. Identification of insect pests of cotton, sunhemp and mesta and their damage symptoms. 7. Identification of insect pests of pulse crops and their damage symptoms. 8. Identification of insect pests of oilseed crops and their damage symptoms. 9. Identification of insect pests of vegetables and their damage symptoms. 10. Identification of insect pests of mango, cashew, banana and their damage symptoms. 11. Identification of insect pests of citrus, sapota, ber and their damage symptoms. 12. Identification of insect pests of grapes, pomegranate, guava and their damage symptoms. 13. Identification of insect pests of coconut, turmeric, betelvine, onion, ginger, tobacco and their damage symptoms. 14. Identification of insect pests of flower, ornamental plants and their damage symptoms. 15. Identification of insect pests of stored grains and their damage symptoms. 16. Study of mite, rodent, bird and nematode pests of crops. Note: Submission of well maintained insect specimens during the final practical examination is compulsory.

The information furnished was collected from various books, websites of ICAR NRCs of different crops, ICAR Directorates of different crops, NCIPM, ANGRAU Vyavasaya Panchangam, ANGRAU Research Highlights, resorce sites of different Agri-Versities.

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The photos given in the manual are taken at RARS, Jagtial, and collected from different resource sites.


References: 1. Atwal AS (1976), Agricultural Pests of India and South East Asia, Kalyani Publishers, Ludhiana 2. Butani DK and Jotwani MG (1984), Insects in Vegetables. Periodical Export Book Agency, New Delhi 3. Pradhan S (1991), Agricultural Entomology and Pest Control, ICAR, New Delhi 4. PAnwar VPS (1995), Agricultural Insect Pests of Crops and Their Control, Kalyani Publishers, New Delhi. 5. Awasthi VB (2007), Agricultural Insect Pests and Their Control, Scientifc Publishers, Jodhpur. 6. Venugopal Rao, Umamaheswari, Rajendraprasad, Naidu and Savithri (2010), Integrated Insect Pest Management, Agrobios (India), Jodhpur. 7. Ghosh SK and Durbey SL (2003), Integrated Management of Stored Grain Pest, International Book Distributing Company, Lucknow. 8. Manisegaran S and Soundararajan RP (2007), Pest Management in Field Crops, Agrobios (India), Jodhpur. 9. Butani DK (1984), Insects and Fruits, Periodical Export Book Agency, New Delhi 10. Khare SP (1993), Stored grain pests and their management, Kalyani Publishers, Ludhiana 11. Nair KK, Ananthakrishnan TN and David BV (1985), general and applied entomology, Tata-McGraw Hill Publishing company 12. Ramakrishna Ayyar TV (1963), Handbook of economic entomology for South India, Government Press, Madras 13. Upadhyaya KP and Kusum Dwivedi (1996), A text book of plant nematology, Arman Publishing House, Meerut 14. Vasantha Raj David (2003), Elements of economic entomology, Popular Book Depot, Coimbatore.

Instructions: • Text given in highlighted format and italics format is important to remember for examination purpose.

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Text given in small font (size 10.5) includes additional information related to the same lecture, which can be utilized by teacher and student for learning important points.

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Lecture: 1 1. Introduction of economic entomology and economic classification of insect pests. The unceasing struggle between man and his insect enemies started even before the dawn of civilization. In spite by the numerous advances made by man in evolving newer and deadlier weapons to fight the war against insects, he has not succeeded in eradicating even one of the thousands of serious pests which damages his food and other agricultural products, destroys his possessions and even attack himself and injure his domestic animals. There generally exists an uneasy truce between the insect’s pests and man, and this is termed as 'balance in nature'. This balance is the result of two opposing phenomena, the 'biotic potential',i.e.,the tremendous capacity of insects to reproduce and multiply and the environment resistance which keeps their numbers under check. The environment resistance results in the death of adults before oviposition, in the mortality of eggs, larvae or pupae of the insects because of desiccation, starvation, parasites, predators, diseases and other adverse environmental conditions. Even any slight slackening of any of the processes of 'environment resistance' results in a population explosion of an insect species and the consequent epidemic. The change in 'environment resistance' may take place owing to a number of causes, either natural or operated by different agencies. Man is perhaps the single most important agent, who has, from time to time, disturbed the 'balance of nature' and this has caused numerous pest problems and pest epidemics. The nature too, plays an important role in causing pest epidemics. Favorable conditions which reduce the natural mortality and bring down the rapid development of the insect coupled with the conditions unfavorable to the natural enemies of that insect, often result in the rapid increase of its population leading to a sudden pest out-break. Insects are the only animals giving challenge to man for his supremacy. They have been upon earth for 300 million years. They occupy more than 2/3 of the known species of animals. About 80 per cent of all the animals are insects. Over 7,50,000 species of insects have been described to date and it is estimated that this number may one day exceed one million). They are found in almost all types of environment (Insects are man’s greatest competition for food and domination of the earth. Most of our crops and livestock or the products derived from them may be damaged by insects. Insects can kill our animals, destroy crops and stored products, demolish buildings and even feed on man himself. These losses do not count the discomfort and suffering insects inflict by direct attacks on people. They feed on almost all kinds of plant, many of which are sources for supply of food clothing and shelter to man. Some insects may superficially scrap the plant tissue, while others invade the plants and stored products. By such infestations, insects inflict direct loss in quantity and weight of these commodities, but in quite many cases, they make the infested materials unmarketable and unfit for human consumption. The annual loss of food due to insects is estimated 15 per cent on an average. Some insects transmit diseases from affected to healthy plants. Insects have great potential for rapid rise in population through a variety of ways. However, many insects are harmless and beneficial to human beings.

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For feeding, reproduction and survival purpose organisms used various types of resources. These resources combined termed as ecological ranges of organism. Similarly insect use the plant resources (phytophagous) for fulfilling their different requirements such as shelter, food, protection from different predators. However use of host plant range is relatively different in the phytophagous insect species. Entomologist classified the plant feeding insect into two categories such as generalist and specialist according to the mode of host plant use by them. Generalist insect can be defined those insect which use wide range of plant species as their host, whereas the specialist insect using a specified range of host plants in their life stages. Again phytophagous insects are differentiated into three categories such as monophagous, oligophagous and polyphagous. The insect species which feed on plants under single genus termed as monophagous. The oligophagous type consumed wide range of plants of different genera but in a single plant family. Whereas a


polyphagous insect refers that they are feeding wide range of plant under different plant families. Most of the phytophagous insects are specialized for choosing their host plant. A study of insect, which affects the interests of man in various ways, is referred to as “Economic Entomology”. Insects can be classified into various groups as per their economic importance (Economic Classification), as given below: Insects Insects possessing economic Importance (Economic entomology)

Insects of no economic importance (Harmless insects)

Insects which are phytophagous can cause injury and damage to plants. By defoliating, or sucking their sap, insects can retard plant growth. By boring into the trunk, stem and branches, they interfere with sap flow and weaken the plant structure. Insects may also carry some plant diseases. Insects may be divided into three categories according to their method of feeding: chewing, sucking, or boring. Insects from each group have characteristic patterns of damage that will help you determine the culprit and the proper treatment. Almost all the parts of the plant are being affected by various insect pests, and in most cases, the species of insect damaging different parts are always unique to the plant Revised during 2011

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b. Pests of stored products (Storage Entomology) c. House hold pests Damage by feeding (pulse beetle, furniture beetle) Contamination by excretion (cockroach) Seeking protection / building nests/tunnels (termites, wasps, meal moth) d. Insects inimical to man (Medical entomology) Causing annoyance: (head louse, bed bugs, eye fly, ants, etc.) Causing irritations on body (ants, wasps, mosquito) Disseminating diseases (mosquito- malaria, rat flea-plaque, housefly- cholera, typhoid, dysentery, diarrhea) Sucking blood (mosquito, horsefly, flea)

Beneficial insects (a) Productive insects Secretion of insects : Silk by silk worm, Lac by lac insects, Wax by honey bees Bodies useful or contain Dye (Cochneal insect), Cantharidin (Blister beetle), Fish bait (stone fly nymphs) Collect and store plant product : Honey (nectar collected by honey bees) Products from plant galls caused by insects: Tannic acid, inks, dyes. Insects as food for animals and human beings (Termites, white grubs, silk worms, pupae, grasshoppers) (b) Helpful insects Aids in pollination (Honey bees, butterflies, fig wasp) Predators and parasitoids (Dragon fly, praying mantis, Chrysoperla, Trichogramma sp,Bracon sp) Destroy weeds: (Mexican beetle, Zygogramma bicolorata feeding on Parthenium). Improve soil fertility: (Ants, crickets, ground beetles, termites) As scavengers: (Dung rollers, maggots, beetles) Ideal material for scientific investigations: Drosphila melanogaster Aesthetic value: (Butterflies, Jewel beetle, clear wing moth)

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Harmful insects (Injurious) a. Pests of crop and plants (Agricultural entomology and Forest entomology) Damage by feeding. Direct (Borers, leaf feeders) Indirect (vectors, whitefly, leaf hoppers) Damage by Non feeding By Egg laying (cow bugs) Using plant parts for Constructing nests (red ants, leaf cutter bee)


species. Based on the insect species affecting parts of the plant, which is usually typical, and the knowledge of the symptoms appearing are very important to understand, as the pest may sometimes disappear from the site of damage. Hence, we need to understand the symptomology (is the study of symptoms present on the different parts of the plant due to the damage caused by the insect pests), so as to identify the pest, assessing the pest damage and also to recommend the proper management practices.

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Based on the nature and symptoms of damage, insects can be classified broadly in to groups: • Chewing insects eat plant tissue such as leaves, flowers, buds, fruits, twigs, roots etc. Indications of damage by these insects are often seen by uneven or broken margins on the leaves, skeletonization of the leaves, and leaf mining. Chewing insects can be beetle adults or larvae, moth larvae (caterpillars), adults and nymphs of locusts, grasshoppers, and many other groups of insects. The damage they cause (leaf notching, leaf mining, leaf skeletonizing, etc.) will help in identifying the pest insect. • Sucking insects insert their beak (proboscis) into the tissues of leaves, twigs, branches, flowers, or fruit and then feed on the plant’s juices. Some examples of sucking insects are aphids, mealy bugs, thrips, and leafhoppers. Damage caused by these pests is often indicated by discoloration, drooping, wilting, leaf spots (stippling), honeydew, or general lack of vigor in the affected plant.

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The following picture depicts that all the parts can be damaged by various insect species. Few examples of insect species affecting tree plants are being illustrated for general understanding.


Boring insects spend time feeding somewhere beneath the bark of a tree or inside the stem or twigs or fruits as larvae. Some borers kill twigs and leaders when adults feed or when eggs hatch into larvae that bore into the stem and develop into adults. The typical damage symptoms include, drying of plant, tree, dropping of fruits, flowers, death of tress, plants, gummy substance ooze from trunk. The following classification of insect pests based on the damage with special reference to the parts they damage, is important to understand: 1. Root feeding insects: Insect larvae feed on roots, root nodules; nymphs and adults suck sap from roots, resulting in stunted growth, poor tillering, drying of plants in isolated patches etc. Eg: White grubs, grubs of rhinoceros beetles, termites, rice root weevil and ragi root aphid 2. Stem borers: Larvae enter into the shoot of main stem, tillers and feed on the central growing point. As a result, nutrient supply from the main plant beyond the infested part is affected leading to withering, wilting and drying up exhibiting symptoms such as dead heart / white ear / over growths of bunchy top etc. Eg: Stem borers of paddy, millets, sugarcane, brinjal, bhendi, cotton etc. 3. Shoot borers: Larvae attack tender shoots and bore inside during the vegetative stage of crop growth and cause wilting, dropping of terminal plant part which later dries up. Eg: Shoot fly of sorghum, early stem borer in sugarcane, stem fly in black gram/ French bean, soybean, shoot borers of brinjal, bhendi, cotton, castor etc. 4. Tree borers: Larvae bore deep into the tree trunk, tunnels in zigzag manner and feed on inner tissues, affecting nutrient and translocation of sap to upper portions of branches / tree exhibiting symptoms such as withering of leaves, drying of twigs or complete dying of tree. Presence of fresh powdered material, ooze of gummy exudations etc. from the affected portion on the tree trunk is also seen in some cases. Eg: Tree borers of mango, cashew; coconut red palm weevil etc. 5. Bark borers: Larvae enter into the bark and tunnel into the branches. The larvae remain hiding in the galleries formed from floss / fecal matter and silken saliva on the stem and continue to scrape the bark. Larval feeding results in drying of branches and breaking of affected portion with wind or gale. Eg: Bark eating caterpillars of citrus, mango, guava, casuarinas, jack etc. 6. Gall formers: Larvae/nymphs feeding inside the stem! tiller /leaf/ flower bud affect the tissue by nibbling the meristamitic tissues and secretion of auxins that results in excessive growth of cells at the affected portion leading to distorted growth and malformation of plant parts known as 'Gall' Eg: Paddy gall midge, chilly midge, gingelly midge, cucurbit stem borer, mango malformations, tobacco stem borer, cotton stem weevil, mango inflorescence midge, chilli midge etc. 7. Leaf folders: Larvae fasten the margins of individual leaves from margins / fold longitudinally or roll leaves into bell shape and feeds within by scrapping the chlorophyll. Ex: Rice/ maize/leaf folder, cotton leaf roller,red gram / black gram leaf folder. 8. Leaf miners: Larvae fasten the leaves /leaflets by means of silken threads (derived from saliva) and scrape the chlorophyll content by remaining within the web. Fecal pellets / frass remain present in the web. Eg: Leaf webbers on groundnut / gingelly, Webbers of mango / sapota /Cashew. 9. Leaf webbers: Larvae fasten the leaves /leaflets by means of silken threads (derived from saliva) and scrape the chlorophyll content by remaining within the web. Fecal pellets / frass remain present in the web.

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Eg: Leaf webbers on groundnut / gingelly, Webbers of mango / sapota /Cashew. 10. Defoliators / Skeletonizers: Larvae feed on the leaves completely leaving only midrib / veins or scrape the chlorophyll content of leaves or cause numerous holes. Eg: Castor semilooper, red hairy caterpillar, bihar hairy caterpillar, snakegourd semilooper, ash weevils, tobacco caterpillar, brinjal epilachna beetle. 11. Pod / Capsule borers: During the reproductive stage of crop, larvae bore into the flowers, pods, capsules and fasten the adsuscent plant parts with silken threads, frass and excreta and feed on the internal contents within the web. Eg: Spotted pod borer in legumes, capsule borers of castor / gingelly ; pod borer complex in pulses, gram caterpillar, pink bollworm, tobacco caterpillar , chilly pod borer etc. 12. Fruit borers / Bollworms: Larvae enter into the tender fruits bolls and feed on internal content /pulp and plug the larval burrow with excreta. Eg: Fruit borer of brinjal /bhendi /tomato, mango fruit borer, fruit fly, mango stone weevil, cashew apple and nut borer, anar/ guava fruit borer, Cotton bollworm etc. 13. Seed feeding insects / stored grain pests: Larvae feed on stored seeds either as internal/ external feeders / by webbing the food particles. Eg: Rice weevil, lesser grain borer, red rust flour beetle, rice moth, cigarette beetle, saw toothed beetle etc. 14. Sap sucking insects / feeders: (a) From tender plant parts: Nymphs and adults suck sap from the base of the plant/leaves / tender terminal plant parts and affect the vigor and growth of the plants. Different insects exhibit different symptoms. Most of the sap suckers suck sap in excess of their requirement and excrete honey dew, which is rich in sugars, a source for sooty mold development. Ex: Aphids, leafhoppers (jassids), plant hoppers, white flies etc on important crops. (b) From grains: Nymphs and adults suck juice from developing ovaries/milky grains resulting in the formation of shriveled /chaffy grains. Eg: Rice gundhy bug, sorghum ear-head bug, sorghum midge.

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Symptoms of sucking pest damage: • Hopper burn (drying of margins), complete drying of plants in patches - paddy brown plant hopper, cotton leafhoppers • Scorch appearance of leaves - paddy leafhopper • Upward curling of leaves - Chilli thrips • Downward curling of leaves and elongation of petioles of older leaves-Chilli white mites • Leaf drying from tip down wards - Onion thrips • Yellowing /crinkling of leaves - Thrips on groundnut, pulses • White / yellow blotches on upper surface of leaves - Thrips in castor, cotton mites, Brinjal mites • Red streaks on leaves - Sorghum/Maize mites • Reduced vigour /sooty mold /yellowing / - Aphids / whiteflies on cotton/brinjal • Corky out growths on fruits - tea mosquito bug in guava • Rotting of fruits - fruit sucking moth in citrus fruit flies in mango • Die back symptoms - tea mosquito bug in cashew


Lectures: 2-5 (INSECT PESTS OF RICE) 2. Major insect pests of rice-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of yellow stem borer and gall midge. 3. Major insect pests of rice-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of BPH and GLH. 4. Major insect pests of rice-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of hispa, leaf folder and ear head bug. 5. Minor insect pests of rice-nature and symptoms of damage and management strategies and IPM practices for grasshoppers, root weevil, swarming caterpillar, climbing cutworm, caseworm, whorl maggot, leaf mite and panicle mite. Rice is the staple food of at least half of the world's population and is grown in approximately 148 million ha of land globally. Nearly 90% of this area falls in the Asian region. Integrated pest management (IPM) is a broad ecological approach for pest management which employs all available skills, techniques and practices such as cultural, genetic, mechanical and biological methods including application of chemical pesticides as a last resort in a harmonious and compatible manner with a view to suppress pest population below economic injury level, based on regular crop pest surveillance and monitoring. The IPM is a dynamic approach and process which varies from area to area, time to time, crop to crop and pest to pest etc., and aims at minimizing crop losses with due consideration to human and animal health besides safety to environment. Live and let live is the philosophy behind IPM. IPM approach has been globally accepted for achieving sustainability in agriculture. IPM has been enshrined as the important principal of plant protection in the overall crop protection programme under the national agricultural policy of the government of India.

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1. STEM BORERS: (Kandam toluchu purugu, Peeka purugu, Tella kanki) Yellow stem borer Scirpophaga incertulas Striped stem borer / Asian rice borer Chilo suppressalis Pink stem borer / Ragi stem borer Sesamia inferens White stem borer Scirpophaga innotata Dark headed borer Chilo polychrysa • Yellow stem borer is the most predominant species distributed throughout the country. • The outbreak years of stem borer are associated with low rainfall. Infestation at the heading stage is assessed based on rainfall received during October-November. • In addition to rice, the pink stem borer survives on maize, sorghum, barley and wheat. Therefore, the dynamics of these pests is of significance in the rice-wheat belt. Distribution: • Yellow stem borer is common in Southeast Asia, China, India, and Afghanistan. • Striped stem borer is present in India, Southeast Asia, China, Iran, and Southern Europe. • Dark-headed borer is an important pest in Malaysia and Thailand. • Pink stem borer is present in the India, China, and Southeast Asia.

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Rice is attacked by insect pests, diseases, weeds, rodents and nematodes. Some of the pests are of national significance, while others are pests of regional significance. Insect pests like yellow stem borer (Sciropophaga incertalas), leaf folder (Cnaphalocrosis medinalis), brown plant hopper (Nilaparvata lugens), gallmidge (Orseola oryzae), white backed plant hopper (Sogatella furciferra), diseases like rice blast (Pyricularia oryzae), bacterial leaf blight (Xanthomonas campestris pv. Oryzae) and sheath blight (Rhizoctonia solani) and weeds like Panicum spp., Cyperus spp. and Echinochloa spp. and rodents such as smaller bandicoot (Bandicota bengalensis), field mice (Musa spp.) and soft furred field rat (Millardia meltada) are pests of national significance.


• White stem borer is found in Indonesia, Philippines, Malaysia, and Australia. • Problematic insect pest throughout state. • Serious problem under late planted and ill drained conditions. Host plants: • Yellow stem borer feeds only on rice plants, while other species feed on barley, sorghum, maize, wheat, and grasses. Marks of identification: Scirpophaga incertulas Pyralidae: Lepidoptera (Snout moths) • The female adult is whitish to yellowish in color, usually bigger in size than males. It has a pair of clear black spots in the middle of yellow colored forewing. The hind wings are pale straw coloured. The body length is 13-15 mm. The male is smaller and is dull in color. It has two rows of black spots at the tip of the forewings. • Eggs are white in color; they are oval, flattened, laid in masses (egg masses) and covered with brownish anal hairs of the female moth.Eggs are usually laid on the leaf tips. (Clipping of leaf tips helps to remove egg masses, during transplantation). • The larva is an internal feeder, has a pale hairless yellow body with a small orange head. • Pupation inside the stem with an exit hole. Full grown caterpillar is about 2.5 cm.

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Nature of Damage: • All rice stem borer species cause the same crop injury and damage to rice plants. • Caterpillar alone is destructive. The larvae cause damage both the vegetative and heading stages of the crop. • The newly hatched larva often wandering on leaf blade hangs down by silken thread and gets blown off to adjoining plants. The larva enters the leaf sheath and feeds for 2-3 days and bores into the stem near the nodal region. Usually only one larva is found inside a stem. They then feed on the tissues around the node as a result of which infested stems are weakened and are easily broken. Some borers eat through the nodes and bore right down the stems, others leave the stem above the node and either enters another tiller or a neighboring inter node of the same stem. At the vegetative stage, the central leaf whorl does not unfold due to larval feeding and turns brownish and dries off, resulting formation of dead heart during vegetative stage or white ear (chaffy earheads) during flowering stages which can be easily pulled out. Symptoms of damage: • The curling of youngest seedling leaf or the presence of egg batches on the upper or lower surface of the leaves. • Often the adult moths are seen in the vicinity of the young plants. • Stem borer larvae feeds inside the stem results in the formation of dead heart during vegetative stage or white ear during flowering stages which can be easily pulled out.


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Life History: Of the different species of stem borers reported on paddy, the yellow stem borer (Scirpophaga incertulas) is the most important in India. This has been reported as a major pest from Andhra Pradesh, Maharashtra, Orrisa, Tamilnadu, Kerala, Assam, Bihar and West Bengal. • The eggs are laid in small masses of oval shape of 80-150 and are covered by the brown anal hairs of the females, which hatch in about 5-8 days. • The larva that hatches out crawls for 30 minutes along the leaf or hangs down by a silken string and reaches the stem, where it bites a hole near a node and enters the stem. It feeds inside as a borer. • The caterpillar pupates in about 40 days inside the stem itself, often near the base within a transparent silken cocoon. Pupa is yellowish-white in colour. The pupal stage lasts for about 8 days. • Adult moth that emerges out through a hole previously made by the caterpillar in the stem. • No alternate hosts are recorded (highly monophagous). Absence of alternate hosts, peculiar boring habit of the larva makes it more difficult to control. • There are three (generations) broads first Kharif / Abi) crop and two in second (Rabi / Tabi) crop period. It is serious in first or main crop season in coastal districts while in Telangana it is serious in second crop season. • The entire life cycle is completed in about 52-71 days depending upon the climate. Seasonal Occurrence and Factors of Abundance • The stem borer attacks the crop in both kharif (Abi) and rabi (Tabi) seasons. • The first appearance of the moths is observed in June but they are more active from September-October till May. • Serious problem in late planted kharif crop and ill drained conditions.

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Dead-hearts are the dried- up central shoots of tillers while whiteheads are the discolored panicles with empty or partially filled grains. These visible symptoms vary at the plant growth stages at which infestation begins. Seedlings and tillers attack at the base of the stem have dead-hearts. An attack on the bearing panicles usually produces whiteheads. Transparent or yellowing leaf sheaths. The damaged leaf sheaths have transparent patches that sooner turn yellowish-brown and eventually become dry. Presence of entrance or exit holes on the stem. Stem borers eat through the node and bore down the stem. They leave the stem above the node and enter in either another tiller, or at the neighboring inter-node of the same stem. Larvae feed on the tissues around the node causing the stem to break. The signs are the tiny holes on the stems and tillers. Fecal matters are found inside the damaged stems. Frass at the feeding site is common when recent feeding has occurred.

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The rabi crop always suffers more due to the stem borer and the number of broods vary from area to area. • Rice fields receiving high rates of nitrogenous fertilizers are preferred by stem borer moths for oviposition and are suitable for larval growth. • Higher incidence was also recorded on acid soils than on neutral and alkaline ones, the damage reported to be more intense in silica deficient plant. • Fallows having high nitrogen fertilizer attract more stem borer moths for egg laying and suitable for larval growth. • The outbreak years of stem borer are associated with low rainfall. Infestation at the heading stage is assessed based on rainfall received during October-November. Management: • Harvesting of crop close to the soil surface (removes larval, & hibernating pupal stages). • Deep summer ploughing after the harvest • Burning the stubbles after harvesting. • Flooding the field. • Provide proper drainage in problematic areas so as to avoid water logging condition. • Grow tolerant varieties like Vikas, Ratna, RP-2812, RP-2815, Goutami, RP825-7-1, IR-20, IR-26 in endemic areas. • Clipping the tops of leaf blades before transplanting (aids in removal of egg masses). • Seedling root dip with chlorpyriphos @ 0.02% for 12-14 hours before transplantation. • Application of carbofuran 3G @ 1.5kgai/ha in nursery 5 days before pulling, protects the crop in main field up to 30 days. • Avoid aged seedlings, if possible. • Moths can be collected by setting Light traps and killed. • Moths can be monitored by pheromone traps @ 4 traps/acre. • Using the natural enemies like egg parasites-Tetrastichus schoenobii, Telenomus beneficiens, Trichogramma sp.; Larval parasites: Amauromorpha accepta schoenobii and Isotima javensis. Release Trichogramma @ 1 lakh/acre. • For an effective control of the pest, insecticide spraying should be taken up at vulnerable stages of the pest viz., at the time of brood emergence (from light traps), and when majority of eggs hatch and larvae are found in wandering stage to entire the stem. • When moths and egg masses are observed, apply phosvel (Leptophos) @ 2 ml/lt, repeat the treatment in 7-10 days if needed. • Application of granules of mephosfolan 5G (Cytrolane-American Cynamide-Systemic) @ 3-4 kg or carbofuran (Furadan) 3G @ 8-10 kg or diazinon 5G @ 8-10 kg per acre at 25 and 40 DAT (days after transplantation). • Otherwise during moderate incidence, the granular application may be substituted with spraying of endosulfan or phosalone 35EC at 1.5 ml/lt or quinalphos 25EC or chlorpyriphos 20EC @ 2ml/lt or monocrotophos 36SC @ 1.6ml/lt, or Repeat 7 to 10 days after spray. Economic Threshold Levels: • Moderate to severe in nursery, 5% dead hearts or one egg mass/m2 at planting to tillering stages or one moth/m2 at panicle initiation to booting or flowering stages.

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Nature and Symptoms of Damage: • The newly hatched maggots move downwards between leaf sheath and feed on the growing point (shoot apex) resulting in the stoppage of normal growth (suppression of apical meristem) and results in the formation of long tubular outgrowths in tillers known as ‘galls’ or ‘silver shoots’ or ‘onion shoots’. (Gall is the modified leaf sheath of flag leaf). • The infestation in the early growth period of crop induces vigorous subsidiary tillering. • Tillering stage of the crop is most susceptible. It infests rice even in nursery but usually tillers are preferred. Tillers affected by the pest don’t form panicle.

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2. GALL MIDGE: (Ulli Kodu) (Silver Shoot) (Onion shoots) Orseolia oryzae (Wood-Mason) Cecidomyiidae:Diptera Distribution: • The Asian gall midge is an important pest and can cause significant yield losses of 3040% in some areas like Sri Lanka and parts of India. • The paddy gall-fly or gall midge is found in most of the paddy growing areas in the southern and eastern parts of India. • The Asian rice gall midge is found in irrigated or rain-fed wetland environments during the tillering stage of the rice crop. • It is also common in upland and deep-water rice. • Severe in Warangal, Srikakulum, Karimnagar and Nizamabad Districts. Host range: • Wild rices, such as Oryza rufipogon are common alternate hosts. • A number of grasses growing in and around rice fields are found to be alternate hosts for gall midge. • It feeds and breeds on number of grasses such as Paspolum scrobiculatum, Panicum sp. Cynodon dactylon, Ischaeum chiliare. Marks of identification: • The adults are nocturnal and they are easily collected using light traps. Adult is mosquito like dipteran fly with slender long legs & orange color body. The female fly has bright red abdomen, & male is darker in colour. Female is swifter with reddish telescopic body. • Elongate pinkish eggs laid either singly or in clusters at the base of leaves. • Maggot is light yellow or pale red colored legless larva (apodous- tapering at the anterior end) feeds on shoot apex and flag leaf gets converted in to hollow onion shoot. • Pupation occurs in onion shoot (at the base of the gall), and pupal exuvae can be seen projecting outside of the gall. • During the dry season, the insect remains dormant in the pupal stage. They become active again when the buds start growing after the rains.


Life History: • The female fly lays 13-320 reddish elongated eggs on the leaf blade or sheath. • The maggots hatch in 3-4 days move down wards between the leaf sheaths to shoot apices and feed on the growing point, resulting into the stoppage of normal growth and gall is produced. • The maggots pupate at the base after 15-20 days. Pupal period lasts for 2-8 days. • The adult flies survive for 1 to 3 days. 5-8 broods spending entire larval and pupal period inside a single tiller.

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Seasonal Occurrence and factors of Abundance • The fly becomes active at the onset of the monsoon, when it completes one to two generations on ratoons or grasses and then finally migrates to the newly planted rice crop. • The peak infestation of gall midge fluctuates between August to November and depending upon the climate conditions. So that late planted first (kharif) crop i.e. plantings made from mid-August to mid-September are seriously infected by this pest. • The years of most gall midge infestations are those when early rain makes the flies active but subsequent dry periods delay planting (delayed planting due to early rains followed by subsequent dry periods). • The population density of the Asian rice gall midge is favored mainly by cloudy or rainy weather, cultivation of high-tillering varieties, intensive management practices, and low parasitization. • The continuous light rainy and cloudy weather in July-September coupled with high humidity favour the buildup of the pest. • The incidence is higher on crops receiving higher doses of nitrogen in alkaline soils. • This pest is mostly confined to first crop i.e., Kharif crop only. It also occurs in second crop but the incidence is very low. Its active period extends from 2nd week of July to end of September.


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3. PLANT HOPPERS: (Doma potu, Doma kaatu, Sudi tegulu) Brown Plant Hopper (BPH) Nilaparvata lugens (Stal), Delphacidae:Hemiptera White-Backed PH (WBPH) Sogatella furcifera Horvath, Delphacidae:Hemiptera Distribution: • When brown plant hopper (BPH) had first assumed major pest status in India 1972, it was confined mainly to southern states, like Kuttanad area of Kerala, KrishnaGodavari delta, Khammam, Nalgonda, Karimnagar, Nizamabad, Srikakulum, Mahboobnagar, parts of Medak and Ranga Reddy districts of Andhra Pradesh, Tanjore delta of Tamil Nadu. • Later it has spread to Tungabhadra region of Karnataka, Mahanadi delta of Orissa and Bankura region of West Bengal. For the last 7-8 years, it started occurring regularly in Goa, Maharashtra, Gujarat, Chhattisgarh, Bihar, Uttar Pradesh, Uttarakhand, Asom and Tripura. It has even been noticed in Haryana, Punjab and Delhi. • Thus, it has risen to status of number one rice pest in India.

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Management • Avoid late transplanting in endemic areas (Warangal and Jagtial area in AP-NTZ and CTZ). • Growing of resistant varieties like Kakatiya, Surekha, Phalguna, Polasa Prabha, Jagtial Sannalu, Jagtial Samba, Jagtial Mahsuri, Karimnagar Samba, Manair Samba, Kavya, Pothana, Erramallelu, Keshava, Shiva, Bhadrakali, Dhanya Lakshmi, Vikram, RP825-24-7-1, RP-9-4, RP-352, RP-974, WRL-20506, WRL-22585, WRL-17672. • Apply carbofuran 3G or phorate 10G @ 1kg ai/ha in nursery at 10DAS (or) spray monocrotophos 36SC @ 1.6ml/lt or quinalphos 20EC @ 2ml/lt or chlorpyriphos 20EC @ 2ml/lt at 10 and 15DAS. • Seedling root dip with chlorpyriphos @ 0.02% for 12-14 hours before transplantation. This treatment is also effective against rice stem borer, brown plant hopper and green leafhoppers up to 30 days. • Application of granules of mephosfolan 5% G (cytrolane) @ 3-4 kg or carbofuran 3G (Furadan) @ 6-8 kg or diazinon 5G (Basudin) 8-10 kg per acre at 10 and 25 days after planting in endemic areas. • Spraying with monocrotophos 36SC @ 1.6ml/lt or quinalphos 20EC @ 2ml/lt or chlorpyriphos 20EC @ 2ml/lt or endosulfan (Thiodan) 35EC @ 1.5 ml/lt or phosphamidon (Dimicron) 100% EC @ 1 ml/lt. • Spray recommended insecticides before 11AM or after 3PM. • In nature rice gall midge larvae is parasitized at different stages. Heavy building of parasitic population occurs after october (larval parasites, Polygnotus sp., Platygaster oryzae), and hence can be conserved through discriminate use of insecticides. Note: • As soon as one gall or more per square meter or 5% affected tillers/sq.mt are seen, the building up of the pest should be checked by taking one of the above control measures. • Several years’ data suggest that in gall midge endemic areas cultivation of resistant varieties could check the infestation of this pest and followed by need based application of insecticides to control other pests would be a practical approach. Economic Threshold Level (ETL): • One gall/m2 in endemic areas or 5% affected tillers in non-endemic areas. 5% affected tillers is the ETL at mid tillering stage.


WBPH: It was serious problem in Punjab and Haryana from 1975 onwards. However, it has also started becoming a serious problem in many deltas of Andhra Pradesh, Tamil Nadu, Karnataka and Kerala. WBPH has started appearing regularly along with BPH since 1990 in these delta areas, particularly during kharif. At present both BPH and WBPH are occurring together in almost all major rice-growing areas. • In southern and eastern India, where there are two crop seasons, viz kharif and rabi, BPH and WBPH attack crop during kharif, BPH is the most serious problem during rabi. In northern and north-western India where rice-wheat rotation is followed and rice is confined to kharif, WBPH is more serious. • In general infestation of WBPH is more during early crop growth, while BPH becomes serious during later crop growth, i.e. during reproductive phase. Host Range: • Although there are many plants listed as alternate hosts to BPH and WBPH, none of them were able to support a population. Marks of identification: • BPH adult is brownish black with yellowish brown body. It has a distinct white band on its mesonotum and dark brown outer sides. • The adults exist in two forms, macropterous and brachypterous. Macropterous adults or long-winged have normal front and hind wings, whereas brachypterous forms or the short-winged have reduced hind wings. A prominent tibial spur is present on the third leg. The macropterous forms are more numerous towards the end of the crop season or when crop is nearing maturity. These adults will migrate to neighboring fields, which are green. If there is no green crop in the vicinity, these can fly over long distances, i.e. even hundreds of kilometers in search of green rice-fields along with the direction of wind. During the process of migration they can withstand starvation for a few days. Once macropterous adults find a green rice crop, then these settle at the basal portion of crop canopy and start laying eggs. The nymphs that emerge from these eggs feed and develop into brachypterous adults. • These adults lay about 400-500 eggs/female and multiply very fast. The eggs are crescent-shaped and 0.99 mm long. Eggs are thrust within tissues of the middle region of the leaf sheath or midrib which are white, elongated and shaped like curved club. • Nymphs are pale white to brown. The nymph has triangular head with a narrow vertex. Its body is creamy white with a pale brown tinge. Mature nymph is 2.99 mm long. It has a prominent median line from the base of the vertex to the end of its metathorax where it is the widest. This line crosses at a right angle to the partition line between the prothorax and mesothorax. •

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Nymphs and Adults of BPH, Nilaparvata lugens


Nymph and Adult of WBPH, Sogatella furcifera

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Symptoms of damage: • The first sign of brown plant hopper damage (in an apparently green looking crop) is the sudden slumping of green looking crop in patches in the middle of the field. Excessive sap drain from plants results in premature yellowing of leaves, which later dry up, and the whole plant dies in due course. Drying of plants start in isolated patches and spreads in a more or less circular pattern. This type of drying up of plants is called Hopper burn. • Membranous cast skins of hopper nymphs can be seen floating on the water surface in hopper infested fields. • When infested plants are tapped with a stick or hand, tiny brownish white nymphs jump in to the water. • In heavy infested fields, both adults and nymphs can be seen climbing onto tip of leaves, and entire leaf surface is covered with different stages of BPH.

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Nature of damage: • The planthoppers are common in rainfed and irrigated wetland environments during the reproductive stage of the rice plant. • High nitrogen levels and close plant spacing tends to favor both the BPH and WBPH increase. Outbreaks of the insect pests are closely associated with insecticide misuse, especially during the early crop stages. These insecticide sprays usually directed at leaf feeding insects disrupt the natural biological control, which favor the BPH development as secondary pest. • The nymphs and adults cause damage. The nymphs and adults of the insect are usually found at the bases of the canopy, where it is shady and humidity is high. They congregate at the base of the plant above the water level. • They suck the plat sap and also obstruct the flow of plant sap by plugging xylem and phloem vessels with their feeding sheets. • A sooty mold develops on the honey dew secreted by the hoppers at the base of the infected plant. • When the planthopper population increases to above 40-50 per hill, the leaves of infested plants first turn yellow from the tip downwards and later brown, and then plants dry up and this type of drying up of plant is called “Hopper burn”. • The brown plant hopper has been reported to be vector of Grassy stunt virus disease.

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Life History • The macropterous (winged) females migrate from the infested crop of the last season or from the grasses and lay eggs. • The female lays eggs in clusters of 2-16 in the leaf sheath or on the basal portions of the midrib, by lacerating the tissues. An individual female may lay 200-600 eggs in its life span. The eggs are white elongate and their anterior ends are attached to one another. They hatch in 8-12 days. The eggs hatch in 12 days during December when the maximum temperature 27°C and minimum temperature is 13.5°C and relative humidity being 90-91 per cent. • The nymphs are brown (but look whitish when they drop on water). There are five instars before nymph becomes adult. The nymphal development takes 11 to 18 days. • The adult lives for 3 weeks. In early part of the season, females with shorter wings called brachypterous are produced. They are larger in size and lay more eggs than winged females. They remain on the basal portion of the plant. Later in the season, when the number of nymphs on a plant increases, winged adults (macropterous) are produced which migrate to the new crop or grasses growing on bunds. The production of wingless females is inversely proportional to the number of nymphs on the plant. • The total period from egg to adult takes about 42 days. Seasonal Occurrence and Factors of Abundance • The brown plant hopper remains active throughout the year in warm and humid climate. The planthoppers are common in rainfed and irrigated wetland environments during the reproductive stage of the rice plant. • A temperature range of 25-300C and relative humidity from 70-85% are optimum and favour rapid development of the plant hopper. • The plant hoppers prefer low land to upland rice. • High nitrogen levels and close plant spacing tends to favor both the BPH and WBPH increase. • Outbreaks of the insect pests are closely associated with insecticide misuse, especially during the early crop stages. These insecticide sprays usually directed at leaf feeding insects disrupt the natural biological control, which favor the BPH development as secondary pest. • Since thick vegetation is better habitable for BPH, direct sown fields are often preferred to transplant ones. Management • Avoid monoculture of susceptible varieties. • Growing of resistant, tolerant varieties like MTU1010, RP-825-24-7-1, IET-2815, CR94-MR-1523, RP-1045, RP-825-71-4-11, IET-5656, MTU-6024, IET 6315. • Preferably form alleys (alley ways) of 0.3m at every 2m distance. This will permit movement of the air and allow sunlight to reach the base of the plant. It will retard hopper build up and will help application of insecticides to the base of the plant when required. • Examine the crop before recommending an insecticidal treatment as there are some predatory spiders and mired bugs, which keep the brown plant hopper under, control. If sufficient population of these predators is observed, better not to adopt any insecticidal treatment. • Spray any of the following at the boot leaf and flowering stage, per acre Monocrotophos 36%SC 250-400ml/acre Carbaryl 50% WP 800-1100 gms/acre Phosalone 35% EC 400 ml/acre

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Malathion 50% EC 200 ml/acre Phosphamidon 100EC 100-150 ml/acre Chlorpyriphos 20 % EC 400-500 ml/acre Note: The spraying should be done on the basal portion of the plant. Carbofuran 3G (Furadan) 6-8 Kg/acre Phorate 10G (Thimmet) 3-4 Kg/acre Water should be impounded in the field for 6-7 days after application of the granules. • If the pest is noticed in large numbers at pre-flowering stage, apply granules in standing water; Carbofuran 3G @ 12 kg/acre, or Phorate 10G @ 4 kg/acre. Water should be impounded in the field for 6-7 days after application. • If the hoppers appear after flowering or where granular applications not possible, spray monocrotophos 36SC @ 0.2 kg.a.i/ha (500 ml) or Carbaryl 50 WP @ 0.5 kg a.i/ ha Repeat if necessary. Sprayings should be done on the basal portion of the plant. • If hoppers appear when the crop is approaching maturity, dust the crop with Quinalphos 1.5 % D @ 0.15-0.18 kg ai/ha (10-12 Kg/ha). • Conserve biological control agents like, Predatory Spider (Lycosa pseudoannulata), predatory Myrid bug (Cyrtorhinus lividipennis), Coccinellid beetles (Coccinella arcuata, C. reanda, Menochilus sexmaculata), and parasitoids (egg: Anagarus sp, Oligosita sp, nymphal: Haplogonatopus orientalis), through discriminate use of insecticides. Economic Threshold Levels (ETL): • Brown plant hopper: 5-10 insects/hill at tillering stage. At panicle initiation to booting stage 20 insects per hill, while 5-10 insects at flowering stage and after flowering. • White backed plant hopper: 10 insects per hill at tillering stage and 5-10 insects per hill at flowering stages and after flowering.

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4. GREEN LEAF HOPPER (GLH): (Patcha doma) Nephotettix nigropictus Cicadellidae : Homoptera Nephotettix virescens Cicadellidae : Homoptera Distribution: • Green leafhoppers are common in rain-fed and irrigated wetland environments. • They are not prevalent in upland rice. • Staggered planting encourages population growth of GLH. • Problem areas include Nellore, Chittor, Krishna, East and West Godavari, Khammam, Prakasam, Guntur, Nizamabad and Karimnagar Districts in Andhra Pradesh. • Prevalent in areas with continuous cropping with rice. Host Range: • It also feeds on number of grasses, such as Echinochloa colonum, E. crusgalli and Panicum proliferum. Marks of identification: • Nephotettix nigropictus having two black patches in the fore wings of the males. In case of the females only some of them have these patches and are bigger in size than males. • Nephotettix virescens having two black spots in the fore wings of males. Females may or may not have the black spots and are bigger in size than males. Black sub marginal band on the crown is absent.


White and elongate or cigar-shaped individual eggs are arranged neatly and lie parallel to each other in each egg batch. Upon maturation, the egg turns brownish and develops red eyes. • The nymphs of both these species are greenish. Neonate nymph measures 0.9 mm long. It is transparent, white, and shiny. As it matures, it turns yellowish to green with or without black markings on the head, thorax, and abdomen. A mature nymph is 3.1 mm long. The shape of the nymph is similar to that of the adult except that the nymph is smaller and is wingless. • As the insect matures, blackish markings on the abdomen become more prominent as well as the blackish band on the last abdominal segment. Nature of damage: • Both the nymphs and adults feed on the dorsal surface of the leaf blades rather than the ventral surface. Both nymphs and adults of the green leafhopper feed on rice by sucking the plant sap and plugging the vascular bundles with stylet sheaths. • They prefer to feed on the lateral leaves rather than the leaf sheaths and the middle leaves. • N. nigropictus transmit 4 virus diseases of rice viz., Trasitory yellowing, Yellow dwarf Dwarf, Tungro virus • N. virescens transmits two virus diseases viz., rice yellow dwarf and rice stunt. • There are about 6 overlapping generations from March-November. The insect overwinters in the adult stage. Symptoms of damage: • Transmits virus diseases such as tungro, yellow dwarf, yellow-orange leaf, and transitory yellowing. • Plant stunted and reduced vigor. • Number of productive tillers reduced. • Withering or complete plant drying. • Yellowing, erect leaves, reduced tillering and stunted growth due to Tungro Virus. Life History • The female insects the eggs in row under epidermis of leaf sheath and lay up to 53 eggs. • The total life cycle takes about 24 days. • There are five instars before it becomes adult. • Egg period 6 days and nymphal stage 16-18 days.

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Seasonal Occurrences and Factors of Abundance • Normally it is most abundant during the rainy season. • High humidity and optimum temperature appear to be important factors causing its abundance. • The pest population is the maximum in July-August and decreases markedly after a heavy rain. • Excessive nitrogen applications encourages pest. • Staggered planting encourages population growth of GLH. Management • Early clipping off of the infested tips of leaves. • Provide proper drainage. • Removal of the alternate host plants such as Echinochloa colonum, E. crusgalli and Panicum proliferum. • Avoid phorate 3G in main field at 40DAT. • Spray with quinalphos (Ekalux) @ 2ml/lt or chlorpyriphos (Dursban) @ 2ml/lt or phosphamidon (Dimecron) @ 1.25ml/lt or Fenthion (Zebayeid) @ 1.5ml/lt or monocrotophos @ 2ml/lt. • If the populations are high, for immediate knockdown affect, mix dichlorvos (DDVP) @ 1ml/lt with monocrotophos @ 2ml/lt. Economic Threshold Levels (ETL): 2 insects/hill in tungro endemic areas, 10 insects/hill in other areas at tillering stage and 20 insects per hill at mid tillering to panicle initiation to booting stages.


5. LEAF FOLDER / LEAF ROLLER (Aaaku mudatha / Aaaku chuttu purugu) : Rice leaf roller is a misnomer because the caterpillar does not roll the leaf and it is better to call it leaf folder, because caterpillar folds the leaves longitudinally (by fringing together their margins with silken threads and live in the tubes or rolls thus formed). Cnaphalocrocis medinalis (Guenee) Pyralidae: Lepidoptera • Nellore, East and West Godavari, Prakasam, Chittor, command areas of Nalgonda, Khammam, Nizamabad, Karimnagar and Srikakulum are the problem areas. Host Range: • Rice leaf folder also feeds on Oats, Coconut, Echinochloa colona (jungle rice), Eleusine coracana, Barley, Banana, Tobacco, Panicum milliaceum (millet), Sugarcane, wild sugarcane) etc. Marks of identification • The adult insect is a small orange moth with yellowish brown wings. • The wings have 2-3 wavy lines characterized by wavy lines in the center and dark band on the margins of the wings. • The newly hatched larva is greenish white in color. Full grown caterpillar measures ½ in length and is greenish yellow in colour.

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Life History • The female moth lays about 300 eggs. The egg period is about 3-4 days. • The caterpillars remain inside the folds and feed on the chlorophyll and give scorching appearance. The larval period lasts from 15-25 days.

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Nature of damage • The caterpillar folds the leaves longitudinally by fringing together their margins with silken threads and lives in the tubes or rolls thus formed. • They feed on the chlorophyll, resulting in longitudinal and transparent whitish streaks on damaged leaves, whitish membranous tubular folded leaves, which give scorching appearance. • Single caterpillar is capable of damaging several leaves. Symptoms of damage • Longitudinal and transparent whitish streaks on damaged leaves. • Tubular folded leaves (margins of leaf blades are folded). • Leaf tips sometimes fastened to the basal part of leaf. • Heavily infested fields appear scorched with many folded leaves.


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6. RICE HISPA / SPINY BEETLE (Naamala tegulu, tellaku tegulu, majjiga tegulu / taataku tegulu) Dicladispa armigera, Hispidae: Coleoptera. • The rice hispa problem is known in Myanmar, India, Bangladesh, Thailand, Cambodia, Nepal, Indonesia, Laos, Malaysia, China, Pakistan, and Sri Lanka. • The adult is a small, shiny, blue-black beetle about 5.5 mm in length with spines over the body surface. • Females lay an average of 55 eggs singly, partly inserted beneath the epidermis of the ventral surface of rice leaves. • Moist conditions, along with higher temperatures are conducive to its development. • It completes life in 13-20 days averaging 16.5 days. • Rice hispa damage the paddy nurseries as well as the transplanted crop. • The main attack is on young rice, by both adults and larvae. • Soon after hatching, the larvae (grubs) mine into the leaf between the epidermal membranes, scrape the green matter of leaves, producing irregular longitudinal / parallel streaks of white lines / patches. The damage starts from the site of oviposition near the leaf tip and extends towards the base of the leaf blade. • In the younger affected leaves, the leaf tips are white or give dried up appearance. Since a very large leaf area is lost due to infestation, vigorous growth of the plant is inhibited when the insect appears in large numbers either in nurseries or planted fields damage to paddy crop is often serious. • The affected leaves gradually wither and die. • A large number of white lines could be seen on older leaves, which appear glistening, membranous and papery white in beginning and turn into pale reddish or straw color later. • The leaf withers, finally resulting in the drying up of the affected leaf.

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• The pupation takes place inside the leaf fold itself. The pupal period lasts for 6-8 days. • Adults survive for 3-4 days. Seasonal Occurrence and Factor of Abundance • Normally it is most abundant during the rainy season. • High humidity and optimum temperatures appear to be important factors causing its abundance. Management • Early clipping off of the infested tips of leaves. • Removal of the alternate host plants such as Echinochloa colonum, E. crusgalli and Panicum proliferum. • Passing the rope / thorny branches over crop, opens the leaf folds, larva falls down, and can be eliminated by draining the water. • Heavy incidence needs spraying of monocrotophos @ 1.6ml/lt, or chlorpyriphos @ 2ml/lt or cartap hydrochloride (Caldan, Padan) @ 10kg/ha. • Avoid application of carbofuran 3G in main field. • Avoid excess application of Nitrogen fertilizers. • Monitor through pheromone traps @ 10/ha for timely monitoring. • Spraying the crop with quinalphos or chlorpyriphos or phosphamidon or fenthion at 0.5 kg a.i./ha. Economic Threshold Levels (ETL): One damaged leaf per hill or one larva per hill at planting and 1-2 freshly damaged leaf per hill at mid tillering or panicle initiation to booting stages.


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The adult beetle feeds on the green portion of the leaf, leaving only the epidermal membranes. The feeding damage shows as characteristic white streaks along the long axis of the leaf.

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Seasonal Occurrence and Factors of Abundance • Usually heavy rains in July followed by abnormally low rainfall in August and September leads to abundance of the pest. • Steady temperatures with least fluctuations between maximum and minimum coupled with high relative humidity were found responsible for hispa out breaks.

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Life History • The entire life cycle of the insect is completed in the rice plant itself. • Female beetle lays an average of 55 eggs singly, partly inserted beneath the epidermis of the ventral surface of paddy leaves. They hatch in 4-5 days. • The grubs immediately after hatching mine into the leaf tissue, where they feed for 712 days and pupate in leaf mines. • The pupae are also flattened and brown. The pupal stage lasts for 4-5 days. • The adult beetles emerge from the grub tunnel. • Adult beetles migrate from infested field to young rice, causing severe damage along the edges of fields. • Two to three generations in a single paddy season take place.


Management • While planting, leaf tips may be clipped off (nursery leaf tips clipping). • To kill the grub inside the leaf tissue, spray fenitrothion 50EC (Sumithin or Folithion) at 1.5 ml / litre of water or quinalphos 25 EC or phosalone 35EC or fenthion (Lebacyid) at 0.5 kg a.i./ha or malathion 50% EC @ 2 ml/liter of water to check and control the pest from further spread. • Dusting carbaryl 10% or BHC 10% dust @ 10 to 15 kg per acre. ETL: One adult or one grub per hill at planting to pre-tillering stages or one adult or 1 to 2 damaged leaves per hill at mid tillering stages. 7. RICE GRASSHOPPER (Vari Midathalu) Larger Rice Grasshopper Hieroglyphus banian Acrididae:Orthoptera Smaller Rice Grasshoppper Oxya nitidula Acrididae:Orthoptera • Hieroglyphus banian adult is larger green, measuring about 3.75 cm long with three transverse dark lines on the prothorax. Its hind tibia is bluish in colour and the antennae are brownish. • Oxya nitidula adults are smaller, green, about 2.5 cm long, with a longitudinal brown streak on either side of the thorax. • Nymphs are brownish but turn greenish as they grow. • Both nymphs and adults feed on foliage and also on developing ears. • Eggs are laid in the soil on the field bunds in masses • At boot leaf stage of the crop, they nibble at the florets/gnaw into the base of inflorescence causing white ears. • Initial damage starts from leaf margins as irregular cuttings. • Hieroglyphus banian infests rice, sugarcane and millet crops, while Oxya nitidula feeds on rice and various grasses.

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Life History • Eggs are laid in soil or bunds in October-November. • The eggs hatch into wingless hoppers (nymphs) soon after first monsoon rains in JuneJuly months. • They are gregarious in initial stages and disperse later. • One generation in a year. Control Measures • Scraping field bunds (clearing field bunds) to destroy eggs and ploughing the fields at summer beginning. • Dusting BHC 10% dust @ 10-12 kg/acre. • Spraying 0.05% fenitrothion or 0.05% endosulfan


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8. RICE CASE WORM (Gottala purugu) Nymphula depunctalis (Guenee), Pyralidae:Lepidoptera • Rice caseworm is common pest in low lying and swampy fields. • A rice field with standing water increases the pest’s abundance. • Transplanting young seedlings favors the development of the insect. • The insect is commonly found in rice fields in low populations. They inhabit wetland and irrigated environments with standing water. • The adults are nocturnal and are attracted to light traps. • The adult moth is about 5 mm long. It is bright white with light brown and black spots. • Individual egg is circular, flattened, light yellow and has a smooth surface. • First instar larva is pale cream with light yellow head, and the larva turns greenish with age. It has branched and thread-like gills along the sides of the body. • The larva scrapes the green tissue of the leaf with only the white epidermis remaining. The white epidermis appears ladder-like because of the back and forth motions of the larval head during feeding. Grownup caterpillars cut the paddy leaves into short lengths, form tubular cases, remain inside the small cases and feed on the foliage. The larva hides in its case then float on the water surface during the day and crawls to the rice plant with its case to feed. • The pupa is cream in color and about 5.5 mm long. Mature pupa is silvery white. • Severe infestation may be observed occasionally on dwarf, compact, heavy tillering, high yielding varieties during the rainy season. • The rice caseworm feeds on rice during the seedling and tillering stages of the crop. Its damage usually starts in a flooded seedbed but does not occur after the maximum tillering stage. • In badly effected fields, number of these leaf cases could be seen attacked to the plants and the foliage eaten up. • Severely attacked fields show a typical whitish appearance from damaged plant tips. • Sometimes the tubular cases can be seen floating on the water in low lying fields. • The cases can be dislodged easily by shaking an infested plant and they can be readily identified in water.


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Early transplanted crop is prone to severe infestation. Severely attacked fields show a typical whitish appearance from damaged plant tips. Sprinkling a little kerosene on to the water in the field. A rope or bamboo pole may be passed over the crop for dislodging the larval cases from the tillers. Water may be drained for removing dislodged larvae. Dusting with BHC dust @ 10-12 kg/acre or spraying with methyl parathion 50% EC @ 1 ml/litre. ETL: 1-2 cases/hill.

9. RICE SWARMING CATERPILLAR / ARMY WORM Spodoptera mauritia (Boisduval) Noctuidae: Lepidoptera Spodoptera exigua Noctuidae: Lepidoptera • Armyworm larva feeds on almost all agricultural crops. • Found in India, Asia, Australia, New Zealand, Canada, and USA • It is a sporadic pest of paddy. • It is a serious pest in nurseries and marches from field to field. • The young caterpillars feed on the leaves nibbling first at the surface, eating small pieces. As they grow, they become voracious feeders, caterpillars appear in swarms of thousands eat up the whole field and migrates to another and they are also called as Army worms. • They feed at night times and hide in day time. • Polyphagous pest also thrives in grasses. • The larvae can eat the entire leaves of field crops and grasses. When feeding, they chew from the leaf edges until only the midrib is left. They feed on various crops and grasses during their migration, and often bare crops of tender leaves after passing through. They travel from field to field in great numbers, hence the name "armyworm". • Adult is dark brown with a conspicuous black spot on fore wings. The moth has 3-4 cm wingspan and 1.5 cm long. Colors vary from light green, light pink, tan, to dark brown in color. The tiny white dot in the center of each forewing is an important feature to identify the armyworm moth. • The moth is seldom seen because it is active only at night time, either mating or searching for suitable egg-laying sites.

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Spodoptera exigua

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Spodoptera mauritia


The female moths lay eggs on the lower leaves of growing grasses or small grains. Eggs are laid in masses on leaves and covered with grey hairs. Eggs of armyworms are white and are found in clusters. One egg mass contains 200-300 eggs. These turn yellowish when mature. Hatching occurs in about 2-5 days. • The caterpillar is smooth, pale to dark-green color with dull dorsal and sub dorsal stripes. The larva varies its colors according to the species. Sizes vary from 2-4.5 cm long. The larva has 6 small legs just behind the head and 10 fleshy legs at the rear. • The larva eats voraciously as it grows. Young caterpillars feed on leaves by nibbling first at the source, eating only small pieces. As they grow, they become voracious feeders appear in swarms and move from field to field. Nursery and early grown crop is more susceptible to the attack. The full grown caterpillar curls in to round shape, when disturbed. • It digs 3-6 cm below the soil surface to pupate. The pupa is brownish red in color and about 2-3 cm long. Pupation takes about 7-16 days depending on the climatic conditions. Control measures: • Trenching round the field and trapping the caterpillar while migrating to neighboring fields. • Removal of alternate host grasses around the rice fields helps in keeping the pest population down. • Dusting 10% BHC dust @ 10-12 kg a.i/acre or spraying BHC 50% WP@ 0.2% or methyl parathion 50% EC @ 0.033% at 225 litres spray fluid per acre. • Spray Quinalphos, chlorpyriphos, Chlorpyriphos, monocrotophos, endosulfan @ 0.05%. •

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10. CLIMBING CUT WORM (RICE EAR-CUTTING CATER PILLAR) (Rella Ralchu Purugu) Mythimna separata Noctuidae:Lepidoptera • The Northern armyworm, Oriental armyworm or Cosmopolitan armyworm or Rice ear-cutting caterpillar (Mythimna separata) is a moth of the Noctuidae family. • It is found in China, Japan, Taiwan, South-east Asia, India, Eastern Australia, New Zealand, and some Pacific Islands. • The adults have a wingspan of up to 40-50 mm and vary in colour from fairly uniform dull yellowish-brown to bright reddish brown. The forewings have a small central whitish spot. The hind wings are uniformly grey. Adults, which are nocturnal in habit, are strongly attracted to lights. • The eggs are pale cream, and are laid in lower leaves of grasses, usually between blades or in sheaths, the mass being held in place by a clusters on the sticky secretion. • Larvae [caterpillars] when fully grown are up to 40 mm long. The younger larvae are green, whereas larger larvae are pale greenish-brown with a thin whitish line down the back and dark lines on each side. There are also dark longitudinal lines near each side of the body. The head has a honeycomb pattern on it. Larvae pass through five instars [stages].


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Pupae are reddish brown, and are found underground or beneath stones, etc. The larvae feed on a range of agricultural plants like Zea mays, Sorghum bicolor and Oryza sativa and are thus considered a pest. Cosmopolitan Armyworms are essentially grass feeders and important as pests of pasture grasses, cereals, and maize. This pest appears in swarms. It has the characteristic habit of climbing the paddy plant and cutting the ear heads in addition to damaging the paddy leaves at night times. It generally appears at the ear head stage in November and December months. It appears on serious only during certain years when the tract gets heavy rainfall. Some losses of production of "grass" crops result from feeding by cosmopolitan Armyworm every season, but when populations reach epidemic proportions plants are completely stripped of foliage. Feeding is mostly on leaves but can also be on stalks, and in maize on developing cobs. In recent years populations appear to have been stabilized by parasitic hymenoptera (wasps). The remains of parasitized caterpillars complete with clusters of 10-20 yellow to greyish cocoons can often be seen adhering to plant material or fence posts. Dusting with BHC 10% dust @ 10-15 kg per acre or spraying methyl parathion (metacid) 50% EC @ 1 ml / litre of water or BHC 50% WP @ 0.2% concentration. Dusting or sprayings for this pest should be taken during afternoon or evening hours. Chemicals same in case of swarming caterpillars.

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11. WHORL MAGGOT Hydrellia sasakii, Yuasa and Ishitani, Ephydridae : Diptera • Rice whorl maggot feed on the margin of rice leaves. • Generally damage occurs from the seedling stage to maximum tillering stage. • Adult is small fly dark brown dorsally and olive green laterally. • Maggot is yellowish white, cylindrical, tapering anteriorly with pointed spiracles posteriorly. • The maggot feed on tender tissue in the center of the whorl and thus it is difficult to make out. The maggots feed on the unopened central whorl and nibble the inner most margin of the leaf causing longitudinal blotches as the leaves unfurl. The damage becomes apparent when leaf comes out. • Typical symptoms include, drooping of young leaves near the tip (terminal drying), shrivelled leaves, plant stunting, and delayed maturity, and under heavy infestation, reduced tillering can be observed. • The full grown maggot pupates outside the feeding stalk. • The damage is more in double cropped areas. • If the nursery is not protected, it will spread into transplanted field. • Incidence is particularly more during tillering phase. • ETL: 20% damaged hills up to 30 days after planting.


12. RICE GUNDHI BUG / SLENDER RICE BUGS / PADDY BUGS / EAR HEAD BUG Lecptocorisa acuta Coreidae:Hemiptera Leptocorisa chinensis Coreidae:Hemiptera Leptocorisa varicornis Coreidae:Hemiptera • The ear head bugs attack paddy crop at flowering stage and continue up to the milky stage. • They are called Gundy bugs because of the bad stink, they emit. • Both nymphs and adults suck juice from grains in the milky state which become shriveled and remain chaffy. • Mature grains are not infested. • In the case of earhead bug attack, only some grains are found chaffy whereas the stem borer infested ears are completely dry including the stalk. • High rice bug populations are brought about by factors such as nearby woodlands, extensive weedy areas near rice fields, wild grasses near canals, and staggered rice planting. • The insect also becomes active when the moonsoonal rains begin. Warm weather, overcast skies, and frequent drizzles favor its population buildup. • The population of the rice bug increases at the end of the rainy season. • Rice bugs are found in all rice environments. • They are more common in rainfed and upland rice and prefer the flowering to milky stages of the rice crop. • Adults are active during the late afternoon and early morning. Under bright sunlight, they hide in grassy areas. They are less active during the dry season. In cooler areas, the adults undergo aestivation or diapause in grasses. • They feed on wild hosts for one to two generations before migrating into the rice fields at the flowering stages. • The nymphs are found on the rice plant where they blend with the foliage. There, they are often left unnoticed. When disturbed, the nymphs drop to the lower part of the plants and the adults fly within a short distance. • Small or shrivelled grains, deformed or spotty grains, empty grains, erect panicles are the typical symptoms. • ETL: 1-2 bugs/hill

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Clean cultivation and weed control (alternate hosts). Collection of the bugs by hand nets Dusting a mixture of 10% BHC and 2% folidol dusts at 3 : 1 at 10-12 kg per acre or sevin 10% dust at the same quantity.

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14. RICE SKIPPER Pelopidas methiasHesperidae:Lepidoptera • The diverse microhabitats in upland environment are conducive to the rice skipper’s development. • Droughts, downpours, floods, or misuse of pesticides are favorable for the insect because beneficial organisms, which held them in check, die. • Rice skippers are found in all rice environments. • They are most abundant in rainfed rice fields. • The adults are diurnal. • At nighttime, they rest. • They have very fast and erratic flight movement as they skip from plant to plant. • The larvae are nocturnal. They feed on the leaf blades at night and rest during daytime. They also create a leaf chamber where they rest during the day. • The larva uses its mandibulate mouthparts to feed on rice foliage.

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13. RICE EVENING BUTTERFLY / HORN CATERPILLAR Melanitis leda Nymphalidae:Lepidoptera • Feeds on Rice, Sorghum, Wheat ,Grasses , Bamboo, etc. • India, sri Lanka, Pakistan, Bangladesh, Myanmar, malaysia, the Philippines, Mauritius, Madagascar, korea, Japan, Africa, Australia, Southern Arabia and the Bismarck Islands. • Common throughout India, except in the arid northwest region. • Adults usually active at dawn and just before dusk, often entering houses during nights. Adults are weak fliers with jerky flight. Though visits flowers, more fond of over ripen fruits, tree sap and toddy, often more abundant around tapped palm trees. • Adults: upperside dull dark brown, fore-Wing with 2 white pupilled black ocelli, having orange inner borders, hind-wing with 3 ocelli , more prominent in and tail also prominent, wingspan 60-80 mm. • Lay shiny and spherical pearl-like eggs. • Larvae yellow-green larva with body covered by small and yellow bead-like hairs, head with 2 dark purplish horns having black hairs, body wrinkled with dark bluegreen dorsal stripe edged with a line of minute yellow dots. • Pupa chrysalis. • Greenhorned caterpillar is a minor pest, feeds on leaves and defoliate the plant. • The greenhorned caterpillars feed on rice from tillering to panicle initiation stages of the crop.Their potential severity is generally too low to cause yield loss. • Natural enemies usually control their populations and rice compensate from the feeding damage of greenhorned caterpillars. • larvae feed on the margins and tips of leaf blades, and feeding damage causes removal of leaf tissues and veins. • Spray quinalphos (0.05%) or chlorpyriphos (0.05%)


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The insect favors young transplanted rice seedlings. Feeding damage continues until plant maturation. Removal of leaf tissues and veins and sometimes leaving only the midrib Rolling down of leaf tip or folding two edges of the same leaf or two adjacent leaves and tying them with silken threads to make a protective chamber. The symptoms are similar to the damage caused by the greenhorned caterpillar Parasites and predators usually control the population density of rice skippers in the field. The eggs of rice skippers are parasitized by small wasps. Big wasps and tachinid flies parasitize the larvae. They are preyed upon by reduviid bugs and earwigs. The orb-web spiders feed on the adults during flight. A nuclear polyhedrosis virus also infects skipper larvae.

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15. RICE ROOT WEEVIL Echinocnemus oryzae Marshall, Curculionidae: Coleoptera • The adult weevils are dark in colour and are covered with grey scales. • Grubs are apodous and white in colour. • On hatching, the larvae (grub) feed on stem epidermis and then enter the soil to attack the roots. The attacked plants are stunted in growth, gradually turn yellow. • Tillering is very poor and some plants may die even. On investigation of the roots reveal the grubs adhering to them. • Clay or heavy loam soils are suitable for the pest and generally the pest appears in patches. Life History • The adults weevils emerge in June and are seen swimming in the water. • The female weevil lays eggs on rice and other Graminaceae. • On hatching, the grubs feed on the stem epidermis and then enter the soil and attack the roots. The grubs are milky white. The grub has an adaptation to get oxygen by fixing its breathing tubes in the air spaces of the tissues roots of the plant. • Pupation takes place 8 cm below soil level. Late in the season, the grubs go 30 cm below soil level and remain until next year. • Two generations per year.


Seasonal Abundance • The small brown weevils soon after S.W. monsoon showers emerge during May-June from earthen cocoons. • Clay or heavy loam soils are suitable for the pest and generally the pest appears in patches Control Measures • Dipping the seedling for 15 minutes in 0.1% diazinon solution. • Application of neem cake 2 bags (each bag of 50 kg) per acre. 16. RICE THRIPS Thrips oryzae Thripidae:Thysanoptera • Nymphs and adults suck sap from the leaves in the nurseries and the just transplanted crop under drought conditions the infestation will be more severe. • The young leaves are rolled; turn yellow, tips dry and the crop gives sickly appearance.

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NON INSECT PESTS RICE PANICLE MITE / Rice Spinki Mite / Rice Tarsonemid Mites (Vari kanki nalli) Steneotarsonemus spinki • Serious rice pest in several Asian tropical regions, Central America and the Caribbean. • The panicle rice mite is not visible to the naked eye. • The mites are clear to straw-colored and are approximately 250 µm in length. The male has elongated rear legs containing a pair of elongated spines. The legs are carried above the body. Males are highly active and can be seen moving on the surface of the leaf. Females are ovoid-shaped. Larval stages, as well as eggs are about half the size of adults. • Parnicle rice mites are parthenogenetic (virgin females can produce male offspring). The female will then mate with the male offspring and produce eggs. A mated female produces an average of 55 eggs in her lifetime. The lifecycle in the laboratory can vary from 3 days at 86 ºF to 20 days at 68 ºF. • High temperatures and low rainfall are ideal for development of large populations of parnicle rice mites in the field. • Continuous rice culture and the sharing of equipment between fields is also conducive to building damaging populations of the mites. • Feeding takes place behind the leaf sheath. When a new leaf begins development, a female will move to the new leaf sheath, produce male offspring and then establish a new feeding lesion. Thus, damage will often be observed on interior sheaths when the outer sheath is removed. This continues until the mite reaches the leaf nearest the stem. • They also feed on developing panicles from the boot stage to the milk stage of heading. • Panicle rice mites cause damage to plants by directly by feeding on leaf tissue in the leaf sheath and developing grains at the milk stage, and indirectly, by transmitting fungal pathogens.


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During feeding, they inject a toxic saliva. The mites have been associated with sheath rot as well as bacterial panicle blight. The mites can carry sheath rot spores on their body. The mites cause damage to plant tissue which may facilitate entry of fungal pathogens into developing grains and the leaf sheath. This damage to grains results in sterility and deformed grains, straight-head, and parrot-beaking of grains. Crop losses ranging from 5%-90% have been attributed to panicle rice mites a number of countries.

Cultural controls include plouging stubble after harvesting crops, as well as ensuring no re-growth of plant material for winter, fallowing fields, rotation with an alternate crop, cleaning machinery before use in an un-infested field, sampling two weeks after planting to catch mite populations at low levels, and avoidance of second-cropping. Chemical controls are usually not effective because the mites remain present in a water-sealed area of the plant-behind the leaf sheath and near the stem. Thus, systemic miticides may be the best option for chemical control.

FIELD RATS BBC News; Jan 2008: Farmers in India's north-eastern state of Mizoram have lost nearly 88% of their rice harvest after rats ravaged croplands last year, officials say. Nearly 40,000 tonnes of rice are reported to have been lost, with more than 70% of farming families affected. The state's heavy flowering bamboo crops attract hordes of rats, a phenomenon known locally as Mautam. Not only do the rats thrive on the bamboo flowers, they also then go on to destroy the farmers' crops. Rat reward Mizoram agriculture official James Lalsiamliana told the BBC no maize had been harvested in the state either. He said the rats had also devoured other crops such as pumpkin, watermelon, chilli, banana and papaya. "The total cultivation area was reduced during the year to around 75% due to apprehensions of destruction of paddy and other crops by rats," he said. All districts of Mizoram had been affected, with Saiha and Lawngtlai in the south worst hit, he said. There, the loss of rice crops had been almost total. The state's problems have been compounded by farmers not planting for fear that crops will be eaten by the rats. "Most of those who planted lost everything to the rats," Mr Lalsiamliana said. Desperate to control the rising rat population, the state government now offers a reward of two rupees for every rat killed. Hundreds of thousands have been killed in the past couple of years, but the rats keep coming in hordes.

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Millardia meltada Bandicota bengalensis Muridae : Rodenta : Class : Mammalia Soft furred field rat or grass rat Millardia meltada • It occurs in irrigated fields but observed in pastures also. • It is nocturnal and lives in simple burrows. • It breeds throughout the year with litter size of 2-10 young ones. • It is small and slender. Adult weight 100 gm. Total length including tail 19-29 cm, tail 9-14 cm either equal or little shorter than head and body, moderately to poorly haired. The tail is dark above and pale below.

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FIELD RATS:


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Indian Mole Rat or Lesser Bandicoot Rat Bandicota bengalenses • It is an excellent swimmer, often living in flooded rice fields and bunds. • Also occurs in the wheat crop fields and godowns. • It is nocturnal and fossorial. • Hoards large amounts of food in its burrows. • Breeds commonly twice a year with 8-10 young ones in each litter. • Adult weight 325 gm. Length from nose to tip of tail 36-48 cm. Tail 18-20 cm; less than some times equal to length of head and body together, 160-170 rings clearly seen on scaly tail. Ear 2.5 to 2.6 cm in length, thick and opaque. Snout – short, stumpy, pig like. Fur and colour: thick, short and harsh, spines present, dark brown, pale brown or reddish above. • Droppings: Scattered, oval weighing 0.042 gm. • It is widely distributed in India. Lesser bandicoot Grass rat Bandicota bengalenses Millardia meltada • Larger in size. • Smaller in size • Dark greyish in colour with a greyish • Dark brownish grey above and pale grey white belly and a bare tail below with soft fur • It makes larger ramifying burrows in soil • The burrows of this are similar to that of extending to a depth of 1-1.5 m and the mole rat excepting that they are laterally 9-12 m. There are 4 or 5 smaller in length and usually more than openings for the burrow; the entrances one adult rat occupies a single burrow are protected by heaps of excavated soil. It usually live alone one in a burrow Nature and Symptoms of damage • Rodents attack rice at all stages of growth from planting to harvest and if there is opportunity, even they will continue to attack the grain in store. • Freshly sown may be dug up and the seed may be eaten. • Rats also feed on germinating grains, cut and feeds on tender seedlings and also grown up plants in boot leaf stage. • On young rice plants, rodents attack the heart of the stem discarding the leaves. The rodents make the rice stems fall. • Some rodent species may store grain in their burrows. • Large rodents, besides feeding on the cop may cause serious damage to the bunds. Control Measures • Rodent pest management envisages using of poison baiting with zinc phosphide followed by fumigation of residual freshly opened burrow openings with aluminium phosphide tablets (Celphos, quickphos, phosfuma etc.,) for control of rodents in crop fields and threshing floors. This should be planned to cover a larger area. This minimizes reinfestation in the cleared area from surrounding infested region, if any. • Rodent control operation should be taken up before sowing of the crop. The rodent burrows should be marked and the burrow opening closed with moist soil and tagged with flags. The burrows opened out on the next day are active burrows or live burrows. • Then pre-baiting has to be done on the 1st and 3rd day. On 5th day 2% zinc phosphide is added and baits distributed 70-80% kill of rodent population can be secured by the operation. The remaining population can be controlled by fumigating burrows. On 6th day all burrow openings are closed. On 7th day in those reopened burrows aluminium


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RICE FIELD CRAB Paratelphusa hydrodromus Decpoda (Ord) : Crustacea (class) Fam: Gecarimidae Marks of identification: • It is whitish to dark brown in colour with yellowish border. • Eyes are stalked and dark black at the back. • Body measures 0.5 cm in thickness and 4 cm in length. Nature of Damage • Crabs are polyphagous. • They cause damage to rice plant and may also damage bunds and irrigation system. • Crabs mostly feed on nursery and newly planted rice seedlings and feed mainly at night times. • Young seedlings in nurseries and newly transplanted ones in the main field, mostly within a fortnight after planting are damaged. • In the older plants after sheets are cut open and the tender inner portions are consumed. • They mainly feed at night. Symptoms of Damage: • In attacked field bits of leaves and stems can be seen floating in water. In badly damaged fields, patches of cutted plants can be noticed. Life History: The crabs breed throughout the year but mainly in dry season April to June. Control Measures • Local farmers do not use chemicals to crab but they do plant extra seedlings in each hill near the bunds. • It can be controlled by spraying BHC at 0.16% (28 gm / 9 litres of water) or phorate (Thimet 10G) 10% granules application in crab burrows or by spraying methyl parathion at 0.1% during dry season.

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phosphide @ 1.5 gm/ active burrow opening are placed and this will take care of residue rodent population. In Households (single dose poisoning-without baiting): The following mixture may be prepared, and offered to kill the rodents: 1. Crushed wheat, maize, bajra etc 450 gr 2. Sugar 15 gr 3. Edible Oil 10 gr 4. Anticoagulant 25 gr Zinc Phosphide bait formulation For Pre baiting Cereal floor 97 parts Vegetable Oil 3 parts Or Whole/cracked grain 98 parts Vegetable Oil 2 parts 8 grams of the above mixture per active burrow should be placed After two days of Pre baiting Cereal floor 95 parts Vegetable Oil 3 parts Zinc phosphide 2 parts or Whole/cracked grains 96 parts Vegetable Oil 2 parts Zinc phosphide 2 parts 8 grams of the above mixture per active burrow should be placed


Lectures: 6, 7, 8 (INSECT PESTS OF SORGUM AND MILLETS) 6. Major insect pests of sorghum and millets-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of sorghum shoot fly, sorghum stem borer, pink borer, sorghum midge and ear head bug. 7. Major insect pests of sorghum-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of Red Hairy Caterpillar (RHC). 8. Minor insect pests of sorghum and millets-nature and symptoms of damage and management practices of deccan wingless grasshopper, aphids, maize shoot bug, flea beetle, blister beetle, ragi cut worm, ragi root aphid and army worm; Insect pests of wheat - nature and symptoms of damage and management practices of ghujia weevil, ragi pink borer and termites. The millets are a group of small-seeded species of cereal crops or grains, widely grown around the world for food and fodder. They do not form a taxonomic group, but rather a functional or agronomic one. Their essential similarities are that they are small-seeded grasses grown in difficult production environments such as those at risk of drought. They have been in cultivation in East Asia for the last 10,000 years. The millets include species in several genera, mostly in the subfamily Panicoideae, of the grass family Poaceae. Of the major and minor millets (not including those plants sometimes called millet) all of the species are in the tribe Paniceae of the subfamily Panicoideae except for finger millet. The most widely cultivated species (major millets) in order of worldwide production are: Pearl millet (Pennisetum glaucum), Foxtail millet (Setaria italica), Proso millet, common millet, broom corn millet, hog millet or white millet (Panicum miliaceum), Finger millet (Eleusine coracana), Minor millets include: Indian barnyard millet or Sawa millet (Echinochloa frumentacea), Japanese barnyard millet (Echinochloa esculenta), Kodo millet (Paspalum scrobiculatum), Little millet (Panicum sumatrense), Guinea millet (Brachiaria deflexa = Urochloa deflexa). Teff (Eragrostis tef) and fonio (Digitaria exilis) are also often called millets, as more rarely are sorghum (Sorghum spp.) and Job's Tears (Coix lacrima-jobi). India is the world's main producer of millets. Sorghum is second most important millet in India.

INSECT PESTS OF SORGHUM OR JOWAR (Sorghum bicolar) (Jonna)

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1. SORGHUM SHOOT FLY (Jonna Kandam Eeega) Atherigona soccata Rondani Muscidae:Diptera Distribution: • More than 150 species of insect pests damage the sorghum crop, of which sorghum shoot fly is most important in Asia, West Africa, and the Mediterranean Europe. • The shoot fly is found in all sorghum growing areas of India. • Distributed in all sorghum growing areas of Andhra Pradesh. • It is one of the most important pests of sorghum. In case of sever attack by this pest; almost all the young sorghum plants succumb to the attack necessitating resowing of crop. Losses in grain yield because of shoot fly damage average about 5% in India. Alternate Hosts: • Main hosts: Sorghum, Alternative hosts: Maize, Finger millet, Bullrush millet, Rice, Wheat, Several species of grasses. Marks of identification: • The adult male resembles a housefly but is much smaller in size. The female fly is pale to dark grey with three pairs of black spots on the abdomen. There are six and four dark spots arranged in two rows on abdominal segments of female and male, respectively. • Maggots are legless tapering towards head. Fully developed maggot is pale yellow in colour measuring about 10-12 mm in length.


Nature and Symptoms of Damage: • The young larvae (maggot) crawl down inside the sheath. Then they bore into the base of the young shoot, killing the growing point and the youngest leaf. This leaf turns brown and withers (dead heart). • Dead heart can be easily pulled out and gives offensive smell at the cut end.

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Seasonal occurance: • This pest is found throughout the year when hosts are available at the right stage. • Highest population levels are observed in August and September. Population is low during december-june. Life cycle: • The flies are active during morning and evening hours. The sorghum shoot fly adult feeds on honey dew and other sweet material available in nature. • The shoot fly females lay white, elongated, cigar-shaped eggs singly on the undersurface of the leaves, parallel to the midrib. Eggs are laid on 7-8 days old seedlings, or on young tillers. One to three eggs are laid per leaf. Each females lay 25 to 40 eggs on leaf sheath. They hatch after 2-3 days. • After egg hatching, the larvae crawl to the plant whorl and move downward between the folds of the young leaves until they reach the growing point. Four instars lasts for 7-12 days. The full grown (third instar) larvae is 8-10 mm long and has a white or yellowish colour. • Pupation usually takes place in the base of the dead shoot, but sometimes in the soil. The pupal period takes about 7 days. • The total life cycle is completed in 18-25 days.


Control Measures • As the insect affects very large number of plants, use higher seed rate. • Uproot (removal) and destroy infested seedlings and extra plants four weeks after germination may be useful. • Early sowing in kharif, with the onset of monsoon, results in escape of the crop from shoot fly damage. • Seed treatment with Carbofuran 50% WP at 100 gm / kg of seed is very effective. • Row application of granules: 3% carbofuran / 5% disulfoton granules (@ 3g/metre) / 10% phorate (@15gm/metre), at the time of sowing. • Spray in early kharif with carbaryl 50% WP @ 2 kg/ha or Lindane 20% EC @ 250 ml / ha in 450-500 litres of water. Spraying thrice, at 7,14 and 21 days after germination is desirable.

Larva: In general appearance the caterpillars look like maize stalk borer larvae. They are creamy pink with groups of dark spots along the back. The head capsule is brown. When mature they are about 25 mm long.

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2. SORGHUM STEM BORER (Jonna Kandam Toluchu Purugu) (Spotted Stem Borer) (Jonna Kandam toluchu matchala purugu) Chilo partellus Swinhoe Pyralidae:Lepidoptera Chilo zonellus Swinhoe Pyralidae:Lepidoptera Distribution: • Attacks Sorghum, maize, millet, rice, sugarcane, and many grasses. • Major pest of Sorghum and Maize, minor pest of wheat in India. • Distributed in Africa, Botswana, Cameroon, Comoro Islands, Ethiopia, Kenya, Malawi, Mozambique, Réunion, Somalia, South Africa, Sudan, Tanzania, Uganda, Zimbabwe, Asia, Afghanistan, Cambodia, India, Andhra Pradesh, Assam, Bihar, Delhi, Gujarat, Haryana, Himachal Pradesh, Karnataka, Madhya Pradesh, Maharashtra, Orissa, Punjab, Rajasthan, Tamil Nadu, Uttar Pradesh, West Bengal, Indonesia, Laos, Nepal, Pakistan, Sikkim, Sri Lanka, Thailand, Vietnam, Yemen, Benin, Bangladesh, Indonesia, Japan, Taiwan. Host range: • It is also known to infest to varying degrees of very large number of other cultivated and uncultivated plants like sugarcane, various millets, paddy, Johnson grass etc. Marks of identification: • Adult: Adult moths have a wingspan of 20-30 mm. Males are smaller and darker than females. The forewings of males are pale brown. The forewings of the females are much paler and the hind wings are almost white. Adult moth is straw colored with pale yellow grey fore wings with black specks along caudal margin. In males, hind wings are pale straw colored and in females, hyaline


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Seasonal occurrence and factors of abundance : • The moths mainly appear in considerable number after onset of monsoon rains in June and are abundant up to November. Life History • The moth is nocturnal insect and during the day it remains concealed under dried leaves, close of earth. • It lays eggs generally on the underside of leaves. • Eggs are small flattish oval, creamy white in colour, laid in over lapping batches. • The larvae are cylindrical about 25 mm long when fully grown, buff coloured with four pinkish brown longitudinal stripes. The caterpillars soon after hatching feed on tender

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Nature and Symptoms of damage: • Newly hatched larvae initially feed on the leaves causing numerous small holes in leaf lamina (shot holes) (windowing) on unfurled leaves. Sometimes the early stages mine in the leaves, causing yellow streaks. • Later on it bores down inside the funnel, and into the stem thereby causes dead heart in young plants where in sufficient stem formation has not taken place. • The effected plants / dead hearts can be easily pulled up, but the affected plants do not emit bad smell, when pulled up. This condition does not occur in the later stage when the stem is so thick that even a large number of caterpillars can continue to tunnel without leading to any external symptom. • The pest infestation continues up to harvest of the crop. The damaged plants lose their vigor and put forth weak ears. • They also may move down outside the stem and then bore into it just above an internode. • Entry and exit holes can be seen near the base of the stem. • Larval damage after flowering produces white ear. • In older plants the caterpillars sometimes live in the developed heads.


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leaves for a day or two and then bore into the central shots. There are six instars before the caterpillar goes for pupation. Before pupation, the caterpillar prepares a hole for the moth to come out. Pupation takes place within the stem. The pupa is obtect, reddish brown, having 6 spines at caudal end. The moth emerges from the stem through a hole made earlier by the larva (Egg stage : 6 days, larval stage 3-4 weeks, pupal stage 7-10 days.

Control Measures • Uproot the affected stubbles and burn them. • To destroy the hibernating larvae, stubbles are to be ploughed up and destroyed. • Crop rotation helps to reduce the pest occurance. • Use resistant varieties. • The first stage larvae have a tendency to concentrate in the central whorl and this habit has recently proved to be great value in their control. Hence, the best way of dealing with this stage is to place granules of contact insecticides in the central whorl. • Endosulfan 4%G @ 8 kg/ha or carbaryl 4% G @ 12 kg/ha or Lindane 2% @ 15 kg/ha. Granules in general give better control of the borer than the sprays. In the leaf whorls, thrice at 20, 30, 40 days age of the crop granules are to be applied. Granules may be alternated with spray formulation of the same insecticides at the same doses and sprays to be directed towards the leaf whorls. • Spraying carbaryl 0.1% thrice at fortnightly intervals from a month after sowing gives protection.

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3. SORGHUM MIDGE Contarinia sorghicola (Coquillett) Cecidomyidae:Diptera Stenodiplosis sorghicola (Coquillett) Cecidomyidae:Diptera • The sorghum midge or gall midge is one of the most serious pests to sorghum. Marks of identification: • The fly is slender bodied, abdomen bright red in color measuring about 2 mm in length; the wings when closed extend just beyond the tip of the abdomen. • It is small mosquito like reddish fly with one pair of hind wings. • The maggots are creamy white when newly hatched but later on turn orange red.


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Life history: • Female midge numbers are highest between 8 and 11 am, which is when inspections should occur. Monitor midge activity on emerged heads before they start to flower as midge may cause economic damage if present in large numbers, on pre-flowering heads. • The female midge lays up to 50 orange yellow eggs only in flowers / glumes on heads, near the spikelet tip while the spikelet is in bloom just prior to and during flowering, when yellow anthers are exposed. • The larvae feed on developing grains. The larval stage takes 9-11 days. • Pupation takes place in the spikelet or in the soil. The colour is reddish with a darker anterior part. Sometimes pupation takes place in cocoons. • When midge populations are high, losses can approach 100% if control measures have not been taken. A generation is complete in 2 to 3 weeks. • Heavy rainfall reduces midge emergence from the infested heads, but the high humidity before and after increases it. Control: • Clean cultivation: Burning of panicle residues and chaff obtained after threshing will destroy diapausing larvae of the midge. • Adopt uniform date of sowing. • Sowing of varieties that flower at the same time / preferably grow only one variety. • Spray ear heads before flowering with, Endosulfan 35% EC @ 2 ml / litre of water or Carbaryl 50% WP @ 4-5 gm/ litre of water or Lindane 20% EC @ 2.5 ml/litre of water. Note: spray at that time when the blooms first appear on the panicles. • Dusting of 10% carbaryl or 4% endosulfan may be recommended.

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Nature and symptoms of damage: • The maggots/larvae on hatching feed on developing grains (ovary / immature seeds), preventing from normal seed formation, and making them into chaffy. • This causes the seeds to shrivel and become malformed. • In heavy attacks the whole head may be empty of normal grains. • Chaffy grains with round holes indicate the emergence of adult midge. • The presence of maggot within a spikelet can be verified by squeezing it. Red ooze which is the body content of the maggots is squeezed out. • Also in later stages, the empty pupal case can be seen protruding from the glumes.


4. SORGHUM EARHEAD BUG Calocoris angustatus Lethiery (Miridae: Hemiptera) Calocoris norwegicus • Sorghum ear head bug is a very serious pest particularly in certain parts of South India. Although it has been reported to damage a number of cereals and grasses, the sorghum is the main host plant. Marks of identification: • Adults long legged,-Male is green in colour, female is green with a brown margin. • The tiny first stage nymph is with a mixture of yellow and orange red colour. NymphsSlender, green in colour.

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Nature and symptoms of damage: • Both nymphs and adults cause considerable damage by sucking sap from tender grains, which are in milk stage. Presence of large number of nymphs and adults are seen on the ear head. • This huge army of young tiny nymphs soon after hatching begins to suck out the juice from the just developing sorghums. • The affected grains become chaffy / unfilled and get shriveled. • In severe cases, the whole ear head becomes at first blackened and then in due course gets dried. Life cycle: • The adult bugs begin to feed on the sorghum crop as soon as the ear heads begin to make their appearance from the unfolding leaf sheath. • They insert their long cigar shaped eggs generally under the glumes or into the middle of florets. Eggs latch in 5-8 days. • As each bug lays between 150-200 eggs the population of the pest increases by 75-100 times within about a week since the crop begins to attract the adult from surrounding uncultivated grasses. • Nymphs moult 5 times in 10-16 days. The nymph develops to the adult stage after about a fortnight. • The new generation is again ready to oviposit on many more ear heads, which are still in the tender receptive stages. • Eggs are not laid when the grain becomes hard. Control: • Dusting the ear heads with 10% carbaryl @ 10-14 kg/acre. • Spraying with methyl parathion 50% EC at 0.05% Note: when ¼ blooms appear on the panicle, the control measures have to be taken up.


5. SORGHUM APHID (Penu Banka) Rhopalosiphum maidis (Fitch) Aphididae:Homoptera Aphis maidis (Fitch) Aphididae:Homoptera • Polyphagous. Main hosts are Young leaves of Maize, Sorghum, Barley, Wheat, and other Gramineae. • The sorghum / maize aphid is widespread around the world wherever maize is grown. • It is a small (1-2 mm), elongate, dark blue-green aphid, with purplish areas at the bases of the cornicles, and short antennae, cornicles and cauda. Adults are black/green with dark green legs, winged or wingless. • Nymphs are yellowish.

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It may build up in dense colonies on leaves, and sheath covering the earheads. Leaves, leaf sheaths and inflorescenses are infested with colonies of aphids. The leaves may become mottled and distorted. Inflorescenses can become sterile. Colonies of aphids are present in the central whorls with association of ants. Both nymphs and adults suck sap from leaves and earheads. Sooty mould develops on infested parts due to the excretion of honey dew. Infested leaves exhibit mottled appearance with yellow patches. Grains do not develop in the affected earheads. New growth may remain dwarfed. Heavy attacks cause the plant to wilt and die. In case of severe infestation, earheads do not exert fully from the flag leaf. These aphids are known to be a vector of virus diseases. Spray 0.02% Phosphamindon, 0.04% Diazinon, Methyldemeton or Dimethoate

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6. SORGHUM MITES Oligonychus indicus Tetranychidae:Acarina • Adult is greyish green, minute in size. • Larva is spherical and light amber coloured larva, later becomes greenish and elongate. • Both immature stages and adult mites spin delicate webbings under surface of leaves and start sucking the sap. • Appearance of red patches on the leaves which later coalesce and increase in size resulting in complete drying and withering of leaf . • Dry and hot weather congenial for rapid mulplication of mites. • Dust sulphur or spray 0.05% wettable sulphur


7. RAGI PINK STEM BORER Sesamia inferens Noctuiidae:Lepidoptera • A serious pest in peninsular India and South East Asia. • This is a serious pest of ragi and also damages maize, bajra, paddy, sorghum, sugarcane, wheat, barely. oats and various grasses. Marks of identification: • Moth is medium size, stoutly built, with straw colored fore wings with a midlongitudinal dark brown broad triangular streak. • Hind wings are white. • Caterpillar in pink color.

Nature and symptoms of damage: • Newly emerged larvae, remain in group behind the leaf sheath, and begin chewing on the stem and epidermal layer of the sheath, while others penetrate stem. • Whorl feeding of larvae, results in rows of oblong holes in unfolding leaves, unlike round shot holes produced by Chilo partellus.

Fully grown larvae in pink color, bore into central shoot, resulting in drying up of the growing part and formation of dead heart in young sorghum and maize plants. • As a result of bottom feeding, sometimes the bottom internodes show circular ring like cuts. The caterpillar migrates from the plant to another injuring many plants in their life time. In a stem sometimes up to five caterpillars can also be seen. Severe damage causes stem to break. Life cycle: • The female moth lays yellow eggs in rows within the leaf tissues, 30-100 eggs per batch. Eggs are roundish, pearl like and yellowish in colour. • On hatching the caterpillars bore inside the stem. Incubation period is 7-12 days. The caterpillars have the migratory habit and become full grown in 25-54 days. • Pupation takes place inside the stems. Pupa is thin, slender, 16-20 mm long, reddish brown with purple tinge near the head region. • The adult moth emerges out in 8-12 days. Adult longevity is 4-6 days. • Total life cycle lasts for 46-83 days. • There are 4-5 generations in a year. Control methods: • The dead hearts and affected plant parts to be pulled out along with larvae or pupae and destroyed by burning. • Follow chemical control measures suggested for sorghum stem borer.

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8. HAIRY CATERPILLAR (gongali purugulu) Red hairy caterpillars: Amsacta albistriga Arctiidae:Lepidoptera (Tiger moths) Amsacta moorei Arctiidae:Lepidoptera (Tiger moths) Black hairy caterpillars: Amsacta (Estigmene) lactinia Arctiidae:Lepidoptera (Tiger moths) • Among the hairy caterpillars, red hairy caterpillars are most injurious to agriculture throughout India. Although the red hairy caterpillars found in Southern and Northern regions of the country are said to belong to two species of the genes Amsacta, then habits, nature of damage etc., are similar. • They are polyphagous. This is a serious pest and devastating pest of rainfed of ground nut crop. • It is an endemic pest and their seasonal outbreaks in various tracts are largely dependent on climatic conditions and the local agricultural practices. It appears in great numbers as regular plague after the receipt of first monsoon showers during early June. Marks of identification: • Amsacta albistriga: The adult is a medium sized moth. The forewings are white with brownish streak all over and yellow streak along the anterior margin and the hind wings with black markings. An yellowish band is seen on the head.

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Nature and symptoms of damage: • The caterpillars in early stages are found in groups on the underside of the leaves and feed on them by scrapping. Later they disperse to surrounding plants and defoliate plants. In years of severe out breaks, field after field may have to be re-sown in the beginning of the season and later on it becomes too late even for re-sowing. • The caterpillars feed up to about September. Revised during 2011

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Amsacta moorei: The anterior marginal streak of forewings and the band on the head are red in colour. Other characters look similar to A. albistriga. Full grown caterpillars of both these species are reddish brown with black bands on either end and have long reddish brown hairs all over the body arising on warts. Amsacta lactinea: (Black hairy caterpillar): The adults are stout, with white color foreand hind wings. Fore wings anterior margin is in red colour. The larva are stout with dense black colour hairs over the body. Commonly seen but not in large numbers, compared to red hairy caterpillars.

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Life cycle: • Eggs are laid in batches of hundreds on the leaves/vegetation. The larva becomes fully grown in a month, reddish brown with dense hairs all over the body. Pupation takes place in soil generally outside of the fields within larval exuave, hairs and dry leaves, under stem. Control methods: • The red as well as black hairy caterpillars are the most difficult pests to control by means of conventional insecticidal treatments, particularly if the control measures are delayed till the larvae reach the advanced and fully hairy stage at which their damage becomes more spectacular and when they generally attract serious attention. • Camp fires: Dried leaves or trash may be burnt near the fields during the night as the moths are attracted by light and get killed in the fire, thus reducing their population (During June-July months they emerge from the soil during the monsoon in several successive waves, the first of which comes up soon after the onset of the rains. • The egg masses of these pests are quite large in size and very prominent against the green background of the foliage on which they are laid. The collection of egg mass is a very practical method of effective control of the pest. • In its early stages, the larvae of the pest are found in groups on the under surface of leaves at this stage it is easily controlled by dusting Carbaryl @ 10-12 kg/acre. • When the caterpillars grow to about 1" in size, spraying endosulfan 35 EC @ 450 ml in 300 litres of water or DDVP 100% EC @ 60-80 ml in 300 litres of water or methyl parathion 50% EC @ 300 ml in 300 litres of water or dusting toxaphene dust @ 10-12 kg/ac. • Digging trenches around fields with malathion dust helps in killing migrating / marching populations. • If the pest is not controlled in the neighboring fields or there are fallows surrounding the treated plots, the sprayed plots need to be further protected from the onward marching caterpillars. This could be done by placing shots of Jatropha (Locally Tella Nephalam/adivi amudam) on bunds. It has been observed that the grown up larvae are attracted to this and when they are in groups feeding on Jatropha leaves, it becomes very easy to kill them by spraying one of the insecticides recommended. • After harvest of the affected crop, the field must be ploughed up to expose pupae.

Adult is yellowish brown to dark brown with translucent wings. Eggs are laid in groups of 1-4 inside the leaf tissues (preferably midrib) and covered over with waxy substances, results in reddening of midrib due to egg laying by adults Revised during 2011

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9. SORGHUM LEAF HOPPER Peregrinus maidis (Ashmead) Delphacidae:Hemiptera (Leaf hopper) • A major pest of Maize, but now it is reported widely on Sorghum also. • Leaf hopper vector of Maize Mosaic Virus (MMV).


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Colonies of nymphs and adults infect tender portions of the plant and such sap. They are found within the whorls inside or on the leaves, secrete honeydew, which attracts sooty mold development. The attacked plants become unhealthy, stunted and yellow. Leaves wither from top downwards, panicle formation is inhibited and plants die in case of severe infestation. Severe infestation causes yellowing of foliage, stunted growth and gives scorched appearance. Ants visit these bugs. Dusting 5% BHC or Folidol 2% dust @ 10-14 kg / acre or spraying methyl parathion 50% EC at 0.04% controls the pest.

10. BLISTER BEELTES Orange banded blister beetle Mylabris pustulata Meloiadae:Coleoptera Brown blister beetle Gnathopastoides rouxi Meloiadae:Coleoptera • Orange banded blister beetle adults attack inflorescence and feed on pollen and petals of flowers and thus adversely affecting grain setting. • It prefers yellow and red flowers. • It also feeds in tender foliage. • Bajra, redgram and cucurbits are the other host plants. • Brown blister beetle adults feed on flowers and tender earheads preventing grain formation.

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11. WHITE GRUB / ROOT GRUB / MAY BEETLES (Vaeru purugu) Holotrichia consanguinea Scarabidae : Coleoptera Holotrichia insularis Scarabidae : Coleoptera Holotrichia serrate Scarabidae : Coleoptera • Root grub is a general pest feeding on the roots of a wide range of plants. • Polyphagous pest. Pulses, groundnut, sugarcane, vegetables etc. • Serious pest in Kurnool and Anantapur districts. • Adults are medium sized beetle with light yellowish / brownish elytra. • Adults emerge out of soil during first monsoon showers. • They are active during May-July months and disappear by first week of August.

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Control Measures • Collection of beetles by hand nets and destroying them. • They may be attracted to light traps. • Dusting 10% BHC @ 10-12 kg/acre.


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Adults fly to near neem, drumstick, babul trees and feed on the leaves. Adults feed on existing trees on the field and mate and lay eggs in soil (up to 10cm depth). The beetles lay the eggs during April-July in small cell in the soil at a depth of 12-15 cm. A single egg per cell. Grubs are fleshy, 'C' shaped (Scarabeiform), whitish yellow in color found close to the base of the roots. Grubs are creamy white with a brown head and reach 2” in length when full grown. They are curled up (C shape) in position. Upon examining one or more white grubs feeding 2-8 cm below the soil surface can be seen. Grubs feed on roots and fine rootlets as a result of which the plants become pale and wilted in appearance and ultimately dry up. Grubs cut end of the stem, and the affected plants, can be easily pulled. Pupation takes place inside the soil Severely damaged plants appear as if drying from drought. Only one generation in a year. Most abundant in light soils.

Control measures • Incorporation of dusts of BHC 10% (45 kg/ha) into the soil before transplantation or application of phorate 10% G @ 2.5 kg ai./ha in two equal splits one at planting and second month after planting. • Destruction of beetles feeding on leaves of trees by spraying carbaryl at 5 gms/litre of water or methyl parathion at 0.05% concentration or endosulfan at 0.05% concentration. • By setting up light traps in the field, the beetles can be attracted and killed.

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12. DECCAN WINGLESS GRASSHOPPER Deccan Wingless Grasshopper Colemania sphenaroides Acrididae:Orthoptera Phadka grasshopper Hieroglyphus nigrorepletus Acrididae:Orthoptera • Eggs are laid in the soil 75-200 mm deep • Hoppers and adults feed on foilage, at times causing severe defoilation of the crops • Adults of C. sphenaroides are wingless, whereas those of H. nigrorepletus are short winged and can fly short distances only. • Destroy eggs in the soil by deep ploughing soon after harvest • Dust hoppers and adults with 5 and 10% BHC respectively


INSECT PESTS OF RAGI 1. 2. • •

RAGI PINK BORER: Sesamia inferens (Walker) (refer in sorghum and maize) RAGI CUTWORM: Spodoptera exigua (Hubner) Noctuidae:Lepidoptera Eggs are laid in clusters on young plants. Caterpillar: Brownish green with wavy lines on dorsal surface and yellow strip laterally. • Pupation takes place in the soil. • Adult: Medium sized, dark brown moth with distinct black spot on fore wings and with white hind wings. • Caterpillars hide in soil during day time and feed on leaves during night time. • In severe infestation, the crop appears as grazed by cattle. 3. RAGI ROOT APHID Tetraneura nigriabdominalis (Sasaki). Aphididae:Homoptera • Both nymphs and adults are pink, globular and small in size. • Both nymphs and adults suck sap from roots causing blackening of the collar region leading to drying of cortical tissues and burnt appearance of secondary roots. • While feeding, they excrete honey dew on which sooty mould develops. • As a result of feeding, plants turn yellow and setting of seeds is reduced. INSECT PESTS OF MAIZE: 1. MAIZE LEAF APHID (Penu Banka) Rhopalosiphum maidis (Fitch) Aphididae:Homoptera Aphis maidis (Fitch) Aphididae:Homoptera Refer to Sorghum aphid 2. MAIZE STEM BORER (Mokka Jonna Kandam Toluchu Purugu) (Spotted Stem Borer) Chilo partellus Swinhoe Pyralidae:Lepidoptera Chilo zonellus Swinhoe Pyralidae:Lepidoptera Refer to Sorghum stem borer 3. PINK STEM BORER Sesamia inferens Noctuiidae:Lepidoptera Refer to Ragi pink borer. 4. MAIZE SHOOT BUG Peregrinus maidis (Ashmead) Delphacidae:Hemiptera (Leaf hopper)

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Refer to Sorghum shoot bug

5. HAIRY CATERPILLARS Amsacta spp. (refer to sorghum) 6. CORN EAR WORM (Patcha Purugu) Heliothis armigera Noctuiidae:Lepidoptera • Heliothis spp are major pests on many important crops, H. zea (Boddie), H. armigera (Hiibner), and H. virescens (F.) being the most devastative. • In India, the three species: H. armigera, H. peltigera Schiff, and H. assulta Gueneeoccur frequently, and H. armigera is by far the most important. • It is an occasional pest on maize. • Larva damage crops eating leaves and cobs. • The pest is seen at Maize plots of Agricultural College, Jagtial in severe form during Kharif 2010 and 2011.


7. TOBACCO CATERPILLAR Spodoptera litura Nctuiidae: Lepidoptera • This is polyphagous, and cosmopolita pest. • Occassional pest on maize, infest and eat away silk, and cobs. • The pest is seen at Maize plots of Agricultural College, Jagtial in severe form during Kharif 2010 and 2011.

8. HAIRY CATERPILLAR Euproctis spp (E. fraterna) Lymantriidae: Lepidoptera • This is polyphagous, and cosmopolitan pest. • Occassional pest on maize, infest and eat away silk, and cobs. • The pest is seen at Maize plots of Agricultural College, Jagtial in severe form during Kharif 2010 and 2011.

Species involved

Type of damage

Sown Seed

Pigeon and House crow

Disturbance of sown and soaked seeds and feeding on them.

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9. BIRDS DAMAGE • The damage by birds is a big problem in maize, and the destruction is more common in boarder rows compared to inner rows.

House crow

Young seedlings are damaged. Aerial portion discarded feeding on the remaining food material present in the seed.

Cob emerging Stage

Rose ringed parakeet

Emerging tender cobs are damaged along with the silky style and green tender spathe(husk)

Milky stage

Roseringed parakeet

Green spathe (husk) are cut into pieces and the cobs are partially exposed and the grains are damaged by feeding on the milky contents.

Dough stage

Roseringed parakeet

The exposed tender grains are removed and fed

Mature stage

Roseringed parakeet, House crow

Green spathe dries up, and the husk is pulled out. The cobs are fully exposed. Grains are fed and cause total damage of the cob.

Management • Damages inflicted by harmful birds can be reduced using a variety of methods which can be categorised as lethal and non-lethal methods. • The best practices followed for protection of maize from bird damage includes, cob wrapping with leaves specially in boarder rows, acoustic methods (engaging labour during morning and evening to repel birds with sounds or dappus), and keeping reflector tapes in the fields. However, the methods followed in detail as given below: • Lethal methods: Lethal methods involve killing of birds, shooting, trapping, fumigation, poison baiting, egg and nest destruction, etc. In past, lethal methods were extensively used to control bird pests in India and elsewhere because killing was considered to be the surest way of getting rid of harmful birds. Killing of any bird species is now illegal in India and also not approved by the public. In view of the above facts, lethal methods of bird management are not recommended these days. • Non-lethal methods: They do not involve killing of birds but instead aim at repelling them from their preferred crops fields. As a result of successful repelling, the damage gets distributed over larger areas and thus no longer remains an economic injury. If alternative foods of the concerned species are available, a part of the bird pressure may shift to such foods which would reduce the total damage to the preferred crop. Non-lethal methods include habitat manipulation, the use of repellents and provision of alternative food to pest bird species. • Habitat manipulation: Bird damage is known to be higher in crops nearer to bird preferred habitats. Habitat manipulation involves removing roosting, nesting and feeding sites or food and shelter from the preferred habitats of harmful birds. The idea is to make these habitats less attractive for birds so that the damages to the adjoining crops may be reduced • Repellents: Substances and devices that cause pest species to avoid the otherwise attrative or palatable materials are called repellents. Bird repellents include several types viz., visual, auditory, chemical plant-based and physical. • Visual repellents: Visual repellents like scare crows have been used in India since ages. The most promising visual bird repellent known so far is the reflecting tape. It is a polypropylene metallic shining tape (11 mm wide, 0.025 mm thick, with one side red and the other silver) Revised during 2011

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that reflects sunlight causing flashing effect and produces a humming noise in wind, thereby scaring birds. It is stretched between poles (with 2-4 twists per 30 m length and enough slack to allow undulation) 0.5 - 1.0 m above the crop, in parallel rows, keeping row to row distance at 3-5meters. Auditory repellents: In India and several other countries, birds have been traditionally scared by producing noise orally, with fire-crackers or by beating drums and empty cans. Automatic acetylene exploders or bird-scaring guns that produce a loud exploding noise periodically have been used to scare birds in some parts of India. All noise producing devices have a major draw-back i.e. birds get used to them quickly. Chemical repellents: Many chemicals when used as seed dressings, sprays or dusts effectively repel birds from crops, thereby reducing bird damage. Seed treatments with Methiocarb [4(methylthio) 3,5-xylyl-N-methyl carbamate] has been found effective in reducing damage by weaver birds and sparrows to sprouting maize. Thiram (retramethylthiuram sulphide), a fungicide, protects sprouting maize from crows. Alternative food: Availability of alternative food is an important factor in determining bird damage to commercial crops. Generally, a scaring technique is more effective if alternative food is available to bird species being scared away.

PESTS OF WHEAT Wheat is susceptible to insect attack in varying degrees from seedling to harvest stages. However, destructive activities of insect pests of wheat are not so severe or frequent as noticed in other cereal crops.

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1. TERMITES / WHITE ANTS Microtermes obesi Termitidae:Isoptera Odontotermes obesus Termitidae:Isoptera • These are polyphagous insect damaging different crops. • The pest has been reported from many parts of the state. • White ants are polymorphic and the workers are only injurious to the crops. Marks of identification: • Workers are whitish yellow flat, soft bodied, generally wingless and soldiers with powerful mandibles. Nature and symptoms of damage: • The workers feed on the cellulose. They usually feed on roots and the stem of growing plant. As a result of their feeding the plant may succumb. • They are polyphagous, feeding mostly on the dead tissues of the plants. • Wilting and drying of all stages of the wheat crop is the major symptom of damage. Life cycle: • Soon after the first monsoon showers, few winged individuals leave the colony for a nuptial flight. After a short flight, mating takes place and the female (Queen) and the male settle down. The female burrows in soil and starts the new colony. • The queen lays eggs very rapidly. They develop into workers. These workers subsequently take care of queen and the colony. Queen termite eggs and nymphs are found inside the termitoria (anti hills). Reproductive forms are winged.


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Control methods: • Locate termitoria, dig out the queen and destroy it. • Fumigate ant hill with carbon disulphide or chloroform mixture. • Soil application of 50 kg of 10% BHC or 5% aldrin dust per hectare at the time of sowing where the termite trouble is regularly observed. 2. STEM BORER – Sesamia inferens (refer in sorghum and maize-Ragi pink borer) 3. ARMY WORM – Mythimna separata (refer in paddy) 4. WHEAT APHIDS – Rhapalosiphum maidis (refer in sorghum / maize) 5. SHOOT FLY – Atherigona spp. (refer in sorghum) 6. WHEAT APHIDS – Rhapalosiphum maidis (refer maize) 7. GHUJIA WEEVIL Tanymecus indius Curculionidae:Coleoptera • Adults are earthern-grey weevils • Grubs feed on roots, whereas the adults cut growing-points or nibble at margins of leaves • Severe infestation at the seeding stage • Plough the fields in summer to expose and kill the pupae • Mix thoroughly 5% BHC with the 12-25 cm deep layer of soil


Lectures: 9-11 (INSECT PESTS OF SUGARCANE) 9. Major insect pests of sugarcane-distribution-marks of identification biology-nature and symptoms of damage and management strategies of early shoot borer, inter-nodal borer and top shoot borer. 10. Major insect pests of sugarcane-nature and symptoms of damage and management strategies of scales, leafhoppers and white grubs. 11. Minor insect pests of sugarcane-nature and symptoms of damage and management' practices of mealybug, termites, whiteflies, wooly aphid and yellow mite. Sugarcane is a long duration crop of 10-18 months and therefore is liable to be attacked by a number of insect pests. According to an estimate, sugarcane production declines by 20% by insect pests. Sugarcane is infested by about 288 insects of which nearly two dozen causes heavy losses to the quality as well as quantity of the crop. The scenario of insect pests varies in sub-tropical and tropical belt of sugarcane. Top borer and stalk borer are found pre-dominantly in sub-tropical areas whereas internodes borer and early shoot borer are prevalent in tropical region. India is one of the principal sugarcane producing countries of the world and has largest area under sugarcane cultivation. Many insect pests damage the crop throughout the reason from germination to harvest. The losses in sugarcane from insect attack affect both yield and sugar recovery.

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Nature and Symptoms of Damage: • The pest attack is usually severe in the early stages of the crop growth during the hot pre-monsoon period. • The attack of the borer is a continuous process from sprouting stage to cane formation. • Even after cane formation, it acts as an inter-nodal borer affecting the internodes. • Usually young plants of 1-3 months old are affected. • Borer infestation during the germination phase kills the mother shoots resulting in the drying up of the entire clump. This leads to gaps in the field. • The caterpillar bores into the growing stem and kills the young plant causing dead heart and in grownup canes, bores into the internodes.

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1. EARLY SUGARCANE BORER / EARLY SHOOT BORER (Peeka purugu) Chilo infuscatellus Snell Pyralidae: Lepidoptera Distribution: • It is the major pest in South India. • It is a serious pest of sugarcane in the peninsular regions of India. Marks of identification: • Moths are small, slender, grayish brown or straw colored with labial palps projected upwards. Males are smaller than the females with a wing expanse of 19-26 mm compared to 23-35 mm in females. A row of white dots are present along the outer margin of fore wings. • Caterpillars are slender, white with brown markings. The tiny spots develop into spines later full grown caterpillar measures 20-25 mm in length. The caterpillar has five violet stripes dorsally and dorso laterally on its body and its head is dark brown.


• •

Life cycle: • Flat, scale like, over lapping eggs are laid in 3-5 rows on the underside of leaf sheath or leaves in clusters containing 8-40 eggs. Each female moth lay about 300-400 eggs. Oviposition period lasts about 4 days. Egg period varies from 3-8 days. • The larvae that hatch out from the eggs get scattered and young larva enters the stem by passing into the space between the leaf sheath and stem making a tunnel by feeding on the inner contents and cutting across the central shoot thereby causing a dead heart. Larval period ranges between 22-44 days depending upon the climate. • Pupation takes place in a pupal cell at the end of the larval tunnel and the pupa is pale straw coloured. After 4-6 days adult moth comes out. • The adult moth survives for 3-8 days. • There are six generations in a year. Seasonal incidence: • Severity of its infestation is well pronounced during summer months of the year. • Attacks the crop during the early part of cane growth, before internode formation. • It also attacks the cane stalks in the years of scanty rainfall. Management: • Systematic collection & destruction of egg masses. • Removal & destruction of dead hearts. • Trash mulching which not only checks the population but also conserves soil moisture and adds the organic matter to the soil. • Planting in deep trenches reduces the borer incidence. • Adjusting the planting (sowing) dates to avoid the peak oviposition period. The infestation can be greatly reduced with November-December planting, and if delayed upto January-February, the incidence will be maximum. • Quick growing varieties escape heavy infestation-attack will be more in thin varieties than in thick ones. • Earthing up: Light earthing-up for 4-6 week old crop may make the stem inaccessible to larvae results in reduced borer incidence (followed by frequent irrigations). Revised during 2011

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•

Larvae initially feed on leaf epidermis and then enter the stem by making a hole just above ground level (entrance hole at ground level). Larvae enter the cane, laterally through one or more holes in the stalks (shoot) and bores downwards as well as upwards killing the growing point. Thus, it cuts of the central leaf spindle, which eventually dries forming a ‘dead heart'. The dead heart can be easily pulled out. The dead heart emits an offensive odour. Borer infestation in cane stalks reduces both cane yield and quality. Causes heavy yield losses as it affects the plant stand/unit area. It also leads to canes of different age, which will be poor in juice quality, with less cane weight. If infested canes are split opened, the larvae or pupae are seen inside.

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By spraying endosulfan 35% EC @ 0.03–0.05% at 4th, 6th, 9th and 12th week age of the crop or application of endosulfan / sevidol granules at 1.5 kg a.i./ha at 4th, 8th and 12th week age of the crop in three equal splits to the soil and leaf whorls. The egg parasites, Trichogramma minutum; T. australicum were reported to have given good control of this pest at many places (Chagallu sugar factory area). Bt formulations found to be very effective against the pest. The pest incidence can be monitored using the pheromones, which are now available in the market (Pheromone Chemicals, Hyderabad). ETL: 15-22% incidence.

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• Larva smooth white or cream colored. Caterpillars are pale whites 2.5 to 3.0 cm long. Nature and Symptoms of damage • The top shoot borer damage starts when the sugarcane is 2-3 months old. • Pest attack confines mainly to the top portion of the shoot. • The caterpillar first bores into the stem from top by tunneling into the mid ribs of leaves, leaving markings on the 2nd to 5th leaves. • From the mid rib it tunnels towards the central core of leaves and enters the shoot. As a result of biting across the spindle a number of shot holes are formed. • Due to damage to the growing point the side shoots develop and give rise to a bunchy top. • It feeds on the growing point, which dries up forming a dead heart. The dead heart is reddish brown and charred cannot be easily pulled out. • Common symptoms of infestation are the appearance of parallel rows of 'shot holes' on leaves, a red streak caused by mining the inside of the midrib, dead hearts and a bunchy top appearance of shoots. Life cycle: • The female moth lays about 250-300 dull white elongate over lapping eggs in clusters, each cluster having 9-79 eggs, usually near mid ribs and covers them with buff colored hairs from its anal tuft. Eggs hatch in 7-9 days into caterpillar. • The larval period lasts for 25-42 days. • It pupates inside the stem. The pupae period lasts for 7-10 days. • The life cycle may range from 40-62 days. • It completes 7 life cycles in a year.

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2. TOP SHOOT BORER / STALK BORER Scirpophaga nivella Fabricius Pyralidae:Lepidoptera Tryporyza nivella Fabricius Pyralidae:Lepidoptera • The top shot borer has a universal (wide) distribution in India but is more serious in North India. Marks of identification: • Moths are medium sized, creamy white, slightly bigger than early shoot borer moth. • Female has tuft of crimson coloured anal tuft hairs at the tip of the abdomen. • In case of certain males, each of the forewings has a black spot.


Seasonal abundance: • Activity of the top shoot borer starts with the onset of the monsoon rains in the north. • Low humidity is unfavorable for the pest. Management: • Collection and destruction of egg masses, collection of affected tillers and destruction. • Spraying of 0.05% endosulfan. • Release of Isotima javensis and Trichogramma minutum parasites during NovemberDecember in Adsali sugarcane is found successful. • ETL: 5% dead hearts in 2nd brood (June end) 3. INTERNODE BORER Chilo sacchariphagus indicus Kapur

Pyralidae:Lepidoptera

Distribution: • The insect is found throughout India. • It is serious on sugarcane in Andhra Pradesh, Karnataka, Kerala, Tamilnadu and Uttar Pradesh. Marks of identification: • Moths are small and are straw colored. • Forewings have a marginal dark line and the hind wings are white. • Caterpillar has a white body with dark spots with four violet or pink stripes, and light brown head.

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Life cycle: • The moths lays the scale like white eggs in batches, each batch containing 9-11 eggs in two rows on the sheath and leaves, in masses near the mid-rib of leaves. The incubation period is 5-6 days. • The larva becomes full grown in 37 to 53 days.

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Nature & symptoms of damage: • The caterpillar bores at the nodal region and enters the stem. • The tissues turn red and the hole is usually plugged with excreta. • A larva may migrate and can attack a number of nodes.


• Pupates in the leaf sheath. The pupal period lasts for 8-10 days. • The total life cycle is about 50-70 days. • There are six broods of the insect in a year. Seasonal abundance: • Usually occurs on sugarcane late in its growing phase. • Its multiplication is rapid under conditions of low temperature and high humidity and the infestation ranges from 20 to 50%. Management: • Collection & destruction of egg masses. • The pest can be controlled by spraying endosulfan (0.05%) at fortnightly intervals from 120 days age of the crop. Normally two sprayings are sufficient. • Inundative release of the egg parasite Trichogramma australicum @ 50,000 parasites/ha/ week. • ETL: 16-28 bored canes / row of 6 m. length

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Nature & symptoms of damage: • Infestation commences with the formation of the internodes, forms a thick and dark encrustation on stem, and continues to increase as the cane plant grows. The shiny encrustation will be maximum on the bottom and middle portion of the cane. • Both nymphs (crawlers) and adult females suck juice and cause shriveling and stunting of canes. • Infestation reduces sugar content and severe cases results in drying of the cane. • In severe cases, even it infests the leaf sheath and the lamina including the mid rib.

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4. SUGARCANE SCALES Melanaspis glomerata (Green) Diaspididae: Hemiptera Distribution: • There are 35 species of scale attacking sugarcane but Melanapsis glomerata is major spp. • M. glomerata an armoured scale is of considerable importance in Andhra Pradesh, Gujarat, Karnataka, MP and Maharashtra. • It is reported that the pest gained entry into AP in 1966 into Nizamabad district and from there to East Godavari district in 1968 and from there to West Godavari and Krishna. Now the pest persists in latter three districts and in the former district it is not of much consequence. In Nizamabad (AP), the pest flares up in July and vividly seen in October to November. In coastal AP seen first in June-July and persists on the crop right up to July. Marks of identification: • Adult scales are grayish black in colour, irregularly oval and slightly convex in shape. • Female are flat and pyriform shape. • The males are winged and smaller in size but are rare. • Freshly hatched crawlers are tiny and light yellowish in colour.


Life cycle: • The adult female is oviparous. The nymphs that hatch inside the adult female come out through the genital aperture (crawlers), crawl about some time and settle down after selecting suitable spot, preferably on the inter nodes. • Freshly hatched crawlers are tiny and light yellowish in colour. • The tiny nymphs after setting down insect their mouthparts into the tissue and start sucking the plant sap. • They remain stationary all through their life in they are female. • The formation of the protected covering i.e., scales starts soon after a nymph gets settled and becomes thicker and increases in size.

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5. SUGARCANE LEAF HOPPERS Pyrilla perpusilla Lophopidae: Homoptera • It is an important pest and becomes an epidemic in certain years. • It is a very destructive sucking pest. • Pyrilla is the most destructive foliage-sucking pest of sugarcane. Marks of identification: • Adults are straw coloured with two pairs of wings folded like a roof on the back and the head prominently drawn forward as a sort of rostrum.

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Seasonal incidence & factors of abundance: • Varieties having persistent leaf sheaths are attacked to a greater extent and a definite correlation exists between number of stomata in the stem epidermis and the intensity of attack. • In a highly susceptible variety of sugarcane, the germination was reduced by about 20 per cent, further the weight of canes, juice sucrose content, bulk and purity reduced by about 13, 47, 28 and 26 per cent respectively. Management: • Plant varieties like CO-70, A-11 (which have a close leaf sheath and are almost selfstripped) in endemic areas. • Immerse the setts before planting in dimethoate or malathion 0.1% solution for at least 15 minutes (or) drench the cane setts kept in the furrow with 0.1% dimethoate solution @ 450-500 litres per hectare before covering them with earth. • When the shoots have at least 6-8 internodes, de-trash the basal 4-5 internodes ensuring that the top most de-trashed node is free from scale insert (Before end of July). • Spraying with 0.1% malathion or dimethoate to the exposed basal nodes twice at intervals of 10-15 days wherever the stage of the crop and its growth permits. • Application of disulfotan 5% G @ 20 kg/acre at the base of clumps 5"-6" deep before July. • Release of predatory Coccinellids viz., Pharoscymnus horni or Chilocorus nigritus in the de-trashed fields after July.


Nature and symptoms of damage: • The adults and nymphs suck the sap from the undersurface of the lower leaves causing yellowish white spots to appear. • When the infestation is heavy, leaves turn yellowish white and wither away. • Due to continuous de-sapping by large number of hoppers, top leaves in the affected canes dry up and lateral buds germinate. • The hoppers exude a sweet fluid (honey dew) on which fungus grows (Capnodium sp.). As a result, the leaves are completely covered by a sooty mould. Life cycle: • About 600-800 pale greenish yellow eggs are laid on the underside of leaves in clusters. They are covered over with a white filamentous waxy material secreted by the parent. Eggs hatch in 7-10 days in summer. • Newly hatched nymphs are milky white in colour with a pair of characteristic processes or filaments covered by wax.

Nymphs are very active and are found in very large numbers on sugarcane. Nymphal period lasts about one to two months. • Life cycle is completed in 2 months. • There are 3-4 generations in a year. Seasonal incidence & factors of abundance: • The loss in yield due to Pyrilla epidemics is approximately 28% and the loss in sugar is about 1.6 units. • Heavy rainfall followed by high humidity (70-80%) and high temperature ((26-30 °C) favour Pyrilla build up. • High levels of manuring, irrigation, waterlogged conditions, and lodging enhance pyrilla build up. • Cane yield loss is about 28% while 1.6% unit loss in sugar content under severe infestation. Management: • Cultural practices like prompt destruction/burning of trash (detrash) after harvest helps in destroying egg masses and over wintering nymphs. • Sowing of tolerant varieties • Mechanical methods of collecting and destroying egg masses in the initial stage i.e., during April-May. • Removal of sprouts from the stubble in april once, helps in reducing the pest buildup. • Detrashing from august onwards very helpful. • During pre-monsoon, dust HCH 5-10% @ 20-30 kg/ha, or methyl parathion 2% @ 12.5 kg/ha or spray chlorpyriphos @ 2ml/lt, or malathion 1ml/lt.

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With the increase in population of the pest, give 1 to 2 sprayings with phosphamidon (0.5ml/lt) or monocrotophos (2.5ml/lt) or dimethoate (2ml/lt), or endosulfan (2 ml/lt), methyl demeton (2.5ml/lt) Stop spraying as the parasites-Tetrastichus pyrillae and Epipyrops melanoleuca appear in the field.

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6. WHITE GRUB Holotrichia serrata Scarabaeidae: Coleoptera Holotrichia consanguinea Scarabaeidae: Coleoptera • Root grub is a general pest feeding on the roots of a wide range of plants. • Polyphagous pest. Pulses, groundnut, sugarcane, vegetables etc. • Serious pest in Kurnool and Anantapur districts. Marks of identification: • Adults are medium sized beetle with light yellowish / brownish elytra. • Grubs are fleshy, 'C' shaped (Scarabeiform), whitish yellow in color found close to the base of the roots. Grubs are creamy white with a brown head and reach 2” in length when full grown. They are curled up (C shape) in position. Nature & symptoms of damage: • Grubs feed on roots and fine rootlets of sugarcane, as a result of which the plants become pale and wilted in appearance and ultimately dry up. • Grubs cut end of the stem, and the affected plants, can be easily pulled. • Severely damaged plants appear as if drying from drought (clumps dryup). Life cycle: • Adults emerge out of soil during first monsoon showers. They are active during MayJuly months and disappear by first week of August. • Adults fly to near neem, drumstick, babul trees and feed on the leaves. • Adults feed on existing trees on the field and mate and lay eggs in soil (up to 10cm depth). The beetles lay the eggs during April-July in small cell in the soil at a depth of 12-15 cm. A single egg per cell. • Grubs are fleshy, 'C' shaped (Scarabeiform), whitish yellow in color found close to the base of the roots. Upon examining one or more white grubs feeding 2-8 cm below the soil surface can be seen. • Pupation takes place inside the soil • Only one generation in a year.


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7. MEALY BUG / PINK SUGARCANE MEALY BUG Saccharicoccus sacchari Pseudococcidae: Hemiptera Marks of identification: • A small pinkish oval insect attached to the lower nodes, protected by leaf sheaths and covered by a white waxy powder. • Adults and nymphs of these bugs are found in large number near the nodes (covered by waxy powder and they are also found in the leaf sheath). • The females are small, pink, sac like/oval with clearly segmented body covered with waxy coating on the body. • Males are winged but rare. Nature & symptoms of damage: • Both the nymphs and adults are found in dense colonies at the lower nodes of the canes and remain protected under the leaf sheath. • The damage caused by the mealy bug S. sacchari occurs partly by sucking the plant sap and so leading to a group of thinner and stunted canes. • While feeding, they excrete honey dew on affected portions that attracts the development of sooty mould and as a result internodes turn black. • The most serious loss, however, occurs from the industrial point of view, as the honey dew excreted by the mealy bug on the cane surface, together with the exudation of gums from parts wounded by the piercing mouth parts of the insects seriously interfere with the raw sugar juice leading to a depression in the amount of sugar crystallized during the manufacturing process. Life cycle: • The female deposits about 1000 eggs covered with a white waxy or mealy mass in the nodal region. Eggs hatch within a few hours and the newly hatched nymphs move rapidly for some time, select a place on plant and settle.

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Seasonal incidence & factors of abundance: • Most abundant in light soils. • The pest is active in monsoon period. • Major pest of adsali crop. Control measures: For grubs: • Ploughing the field deep after the crop. • Application of phorate or carbofuran granules @ 2.5 kg a.i/ha in two equal splits i.e. a) one at planting) one month after planting after making furrows in both sides of cane row, apply and cover with soil or • Incorporation of BHC dust @ 60-75 kg /ha. For adult beetles: • After the emergence of adult beetles in June (after the break of monsoon), they fly to neem or other tress, hence beetles can be killed by spraying carbaryl at 5 gm / litre of water (0.25%) or methyl parathion at 0.05% concentration or endosulfan at 1.5 ml / litre of water (0.05%). • The beetles are active at night and are phototropic in the night times; hence, light traps can be setup during June in the endemic areas. Then beetles can be collected and killed to check from further generation. • Incorporation of dusts of BHC 10% (45 kg/ha) into the soil before transplantation or application of phorate 10% G @ 2.5 kg ai./ha in two equal splits one at planting and second month after planting.


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Ants help in their dispersal to a large extent and they live in symbiotic existence. The total life cycle occupies in about a month.

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8. SUGARCANE TERMITES Odontotermes obesus Termitidae:Isoptera (Refer to Wheat) • Six species of termites have so far been recorded from India, damaging sugarcane viz., Odontotermes obesus, O. assumthi, O. taprobenes, Microtermes anandi, Eremotermes nerapololis, Trinervitermes heims. • These are morphologically different, but their habits, symptoms of damage etc are all alike. • The pest is subterranean. The termites commonly found are called subterranean termites because they live underground. • These are polyphagous insect damaging different crops. • The pest has been reported from many parts of the state. • Termites or white ants are another destructive pest of sugarcane, omnivorous and omnipresent. • White ants are polymorphic and the workers are only injurious to the crops. Marks of identification: • Workers are whitish yellow flat, soft bodied, generally wingless and soldiers with powerful mandibles. Nature and symptoms of damage: • They live under ground attacking the crop, when the setts are planted in the soil and ravages continue till harvest of the crop with slight slackness during monsoon. • The workers feed on the cellulose. They usually feed on roots and the stem of growing plant. As a result of their feeding the plant may succumb. • They are polyphagous, feeding mostly on the dead tissues of the plants. • The termites damage the cut ends and buds of setts affecting their germination. • Setts are completely eaten away having only the outer hard rinds. • In attacked plants, the outer leaves first show signs of drying and the attacked canes may come out easily, if pulled. • The damage may range from 40-50%.

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Management: • Selection of pest free setts for planting. • Destruction of crop residues. • Detrashing • Spray malathion 0.1% or fenitrothion 0.04%.


Its attack results in heavy loss in yield in sugarcane and also reduction in sucrose content (Loss of 2-5% in tonnage and 4.47 per cent in sugar output). • Wilting and drying of all stages of the sugarcane crop is the major symptom of damage. Life cycle: • Termite colonies are highly organized societies of several hundred thousand to 1 million or more individuals within a loose collection of underground tunnels and chambers. • Soon after the first monsoon showers, few winged individuals leave the colony for a nuptial flight. • After a short flight, mating takes place and the female (Queen) and the male settle down. • The female burrows in soil and starts the new colony. • The queen lays eggs very rapidly. They develop into workers. Workers (1/8-inch, creamy white, wingless, segmented body, bead-like antennae) are the most numerous members of the colony. They build and maintain the nest, care for the immature, and forage for food to eat and carry back to the nest. These workers take care of queen and the colony. • Queen termite eggs and nymphs are found inside the termitoria (anti hills). • Reproductive forms are winged. Reproductive, i.e., queens and kings, produce the new offspring, while soldiers guard the colony from invasion. • Swarmers (3/8-inch, straight-sided, black body, silver wings) are male and female adults that emerge from well-established colonies to attempt to establish new colonies.

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Seasonal incidence & factors of abundance: • They are mostly found in light soil. • Their attack is severe in red soils. • Their attack is severe in fields where irrigation facilities are inadequate. Management: • Systematic digging up of termite mounds and destruction of queen is a permanent measure of control. • Fumigate ant hill with carbon disulphide or chloroform mixture.

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Soil application of Lindane 5% G at 1 kg a.i./ha at planting in is found to give satisfactory control or Dusting BHC 5% @ 25 kg /ha along the furrows prior to planting or Aldrin 1 kg a.i./ha or dieldrin 1.0 kg a.i./ha – soil application for standing crop. Chlorpyriphos insecticide working as contact, stomach and fumigants. It is also having longer residual & broad spectrum control. It is mostly used in control of termites.. Active ingredients in currently available termiticides can be broadly classified as repellent or non-repellent. Pyrethroids, such as permethrin and cypermethrin, are considered to be repellent. This means that the termites are able to detect the insecticide, which basically serves as a barrier, and they are repelled by it without receiving a dose that will kill them. Therefore, when using these materials it is important to make sure there are no gaps or breaches in the barrier. Also, any adjoining structures must be monitored to ensure that the repelled termites don't infest them. Recently introduced chemicals (imidacloprid and fipronil) are now available that are less toxic to humans and other mammals than the older insecticides but highly toxic to insects. Both of these insecticides are also non-repellent to termites and have been shown to be effective in killing termites at low dosage rates. Baits for subterranean termites are commercially available in USA, but in India, we do not use these baits.

9. WHITE FLIES Aleurolobus barodensis Mask Aluerodidae:Homoptera Neomaskellia bergii Aluerodidae:Homoptera • Only these two species have been recorded damaging sugarcane in India. • Aleurolobus barodensis is of economic importance and severely infects cane in Bihar, Gujarat, Haryana, Punjab, Tamil Nadu, and Andhra Pradesh. Marks of identification: • Aleurolobus barodensis: Adults are small, fly-like and often dull white in colour. The powdery wax on their membranous wings, give the alternative name 'mealy wing'. Adults measure 1 - 3 mm in body length. Nymphs whitish oval in shape. • Neomaskellia bergii: Adult - Black bands on wings, Nymph - Brownish oval.

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Aleurolobus barodensis Neomaskellia bergii Nature & symptoms of damage: • Both nymphs and adults feed via stylet mouthparts with which they pierce plant tissues and suck phloem sap. The nymphs of white flies suck the sap from the undersurface of the leaves which turn yellow, and pinkish in severe cases, and gradually dry up. • These insects often produce large amounts of sugar-rich excreta, 'honeydew' support the growth of sooty mould caused by fungus Capnodium sp on affected plants, which interferes with the photosynthetic activities of the leaves.


Life cycle: • Whitefly eggs are borne on pedicels. The pale yellow/ whitish adult female lays about 80 eggs in straight rows, usually on the underside of leaves. Fresh unopened leaves in the central whorl are preferred for egg laying. The average number of eggs laid varies with the season. The eggs are fixed firmly on the leaf tissue by a stalk or pedicel at one end and the incubation period varies from 8 - 31 days. The eggs are generally pyriform or ovoid. • The first instar larvae (crawlers) are mobile and can crawl short distances to reach suitable feeding sites. After the first moult, the remaining three larval instars are sessile. The fourth instar is often referred to as a pupa. However, it is not a true pupa as feeding occurs during the first stage and transformation into an adult takes place in the last stage without any pupal moult. The legs and antennae of the 2nd, 3rd, 4th nymphal instars are atrophied, making these instars sessile. • The freshly hatched nymphs are creamy pale and slowly change colour to a shiny black hue. Nymphal stages (1-3) lasts for 15-21 days. • The fourth nymphal instar (pupal stage) lasts for 9 - 14 days.

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Seasonal incidence and factors of abundance: • The sugarcane crop raised in low lying, water logged areas and in semi dry alkaline soils suffers to a greater extent by both these species. • Drought, N deficiency, and waterlogged conditions favor the buildup of white flies. • Affects from August-October. • Varieties with broad and long leaves like Co C 671 and Co 775 are more susceptible to this pest.


Whitefly has been reported to breed well on neglected ratoons, especially in waterlogged areas, which are generally poor in nitrogen content Management: • Avoid excessive use of nitrogen. • Avoid susceptible varieties. • Spray Fenitrothion 50 EC @ 2 lit or moncrotohphos 36 SL @ 2 lit /ha •

10. SUGARCANE WOOLY APHID Ceratovacuna lanigera Zehntner (Hemiptera: Aphididae) • Sugarcane woolly aphid, Ceratovacuna lanigera Zehntner has been recently reported in outbreak proportions from western and southern India. • Sugarcane woolly aphid is a foliage sucking pest has been reported from India, Nepal, Bangladesh, throughout East and South East Asia, Fizi and Solomon IseLands. • In India it has been reported from both tropical (Maharashtra, Karnataka, Gujrat, Andhra Pradesh and Tamilnadu) and subtropical belts (Assam, Nagaland, Tripura, Uttranchal, westen Uttar Pradesh and Haryana). • Woolly aphid earlier was known to be minor pest in India has now assumed the status of economic pest after its severe outbreak in Maharashra during July 2002. • Primary host is sugarcane, and the pest breeds on plants of the family Poaceae, like bamboo and other grasses. • It has been recorded on ten species of plants in India. • Adults: The apterous adult female is 1.78 mm long and 1.07mm wide with a very soft, board, laterally depressed body which is densely covered by white, cotton like secretions. Fifth and sixth segment of abdomen bears circular cornicles which secrets waxy material.

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First instar nymphs produced by alate females are relatively active, have long, elliptical bodies and are pale greenish white in colour, whereas, those produced by apterous females have elongated ovoid bodies and are pale yellowish white in colour. As nymph develops the dorsum is gradually covered by a white powdery secretion. Developed colonies looked like a white woolen mass and that is why this aphid is referred to as woolly aphid.

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11. SUGARCANE MITES Oligonychus indicus Hrst, • • • • • • •

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Tetranychidae:Acarina

It is a harmful pest of sugarcane, maize and sorghum. This species is widely distributed in India. The attack of this mite on sugarcane is more in north India and less in south India and causes 20-30% damage to the crop. In case of sugarcane, maize and sorghum, feeding of this mite causes the appearance of reddish spots which increase with the severity of attack. These spots later coalesce to form large red patches and spread on the leaf surface to turn the colour of the leaf red. The leaves turn red in patches. It is grayish green mite with black blotches scattered over dorsum. There are 30 overlapping generation in a year; all stages occur together living in a delicate web of silk and breeding is continuous. The mite spreads by wind and also by crawling from plant to plant, when leaves touch each other. Adult males feed very little and the main damage is caused by the females and immature stages. Soft leaf varieties of sugarcane are more susceptible to attack than those having hard leaves. Red mite occurs in hot weather mostly in years when a few summer showers are received. The white mite appears a little later in May, June and July. It occurs under characteristic oval webbings and the chlorophyll is depleted in oval patches, wherein in severe cases are extensive. Hot dry conditions favour their increase.

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The sexual phase is not known. Woolly aphid is often parthenogenic reproducing viviparousaly (live birth). These modes of reproduction provide an exceedingly rapid turn aver of generations. C. lanigera lives in large colonies, sucking phloem sap from the leaves and excreting copious honeydew onto foliage leading to the development of sooty mould. Woolly aphid feed on sugarcane by inserting their stylets through the stomata of the plants leaves. Both nymphs and adults suck the cell sap from lower surface of leaves. They suck the sap from phloem. They excrete large amount of honey dew which falls on the leaves giving them a sticky coating on which black sooty mould (Capnodium sp.) develops making the leaves look all black. Due to the thick coating of sooty mould process of photosynthesis is significantly hampered in severely infested plants, thereby, considerable reduction in cane yield (25%) and sucrose content (26.71%), whereas, during the early growth period plants may die. The direct and indirect damage affects sugarcane yield and quality. An early rainy season was the major cause for attack and dry season with high humidity was also conducive for aphid infestation. Long periods of dry and wet seasons inhibited aphid population and alternating rainy and hot days enhanced population growth.

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Economic Threshold Level (ETL) of sugarcane pests Name of the pest Early shoot borer Pyrilla Stalk borer Internode borer Top borer White grub Rodents

Economic threshold level 15.0-22.8% for late variety, 16.8% for early variety. 3-5 individuals/leaf or one egg mass1 leaf+ 17 bored internodes1row of 6 m. length 16.15 to 28.39 bored canes1row of 6 m. length 15-22% incidence 15 beetles/host tree 15 live burrows/ha.

Integrated management schedule for sugarcane pests Target insect pest Borers, mealy bug and scale insect

Selection of seed pieces Pre-planting (seed treatment )

Borers, mealy bug and scale insect Borers, mealy bug and scale insect Scale insect and mealy bug Scale insect and mealy bug White grubs

At planting

Termites and shoot borers Shoot, root and top borers

Shoot borer

Top borer

Black bug Pyrilla

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Pre-monsoon (March-June)

Control measures Seed material should preferably be taken from a healthy crop. No seed should be taken from a crop having pest incidence above 20 per cent Borer infested seed setts should not be used for planting Heat therapy followed by dipping setts in Aretan/Agallol (0.1% solution.) Rubbing of setts with gunny bag pieces dipped in Malathion (0.1% solution.) Dipping setts in Malathion (0.1%) or Dimethoate (0.06% solution.) for 15 min. Two to three extra ploughing to expose white grubs for predation in endemic areas. Application of Endosulphan @ 1 kg a.i./ha over the cane setts in 1600 to 1800 litres of water Removal of egg-masses and infested shoots from the ground level. Copious irrigation and trash mulching. Avoid irrigation at the peak period of top borer moth emergence during summer. Release of Sturmiopsis inferens @ 125 gravid females/ha. Spray granulosis virus of shoot borer at 107 inclusion bodies/ha in 500 litres of water/ ha (tropical India). (i.) Soil application of carbofuran 3 [email protected] kg a.i. /ha or phorate 10G@ 3 kg a.i./ha against third brood (June last week or July first week) of the pest. (ii.) Release of Isotima javensis Rohw against third and fourth broods of top borer. Whorl application of Endosulphan emulsion @ 1.0 kg a.i./ha or Endosulphan 5 G@12 kg/ha 1. Removal and destruction of two lower most leaves bearing egg-masses during April/ May 2. Release of 4000-5000 cocoons and 4 to 5 lakhs eggs of Epiricania melanoleuca per hectare during July-August. Crop having no Epiricania population be sprayed with Endosulphan or monocroptophos @ 1.0 kg ai per hectare.

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Crop stage / period Selection of seed crop


Scales and aphids

White grubs

Thrips Mites Internode borer

Stalk borer,internode borer, pyrilla, scale insect, mealy bug, white flies Pyrilla Scale insect White flies

Stalk borer

Gurdaspur borer Application to most of the pests

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At harvest

Dusting with Malathion spray @ 0.1 per cent or [email protected] litres per hectare. Malathion spray @ 0.1%. 1. Avoid rationing in low lying areas. Spraying with monocroptophos solution @0.3 kg a.i./ha or Endosulphan @ 1.5 lit/ha. Two sprayings of monocroptophos @ 0.75 kg a.i./ha at monthly intervals during September and October after detrashing dry leaves. Regular collection and destruction of infested tops from July till October. 1. Harvesting the crop form the ground level. 2. Removal of late and water shoots. 3. Burning trash and left over dry canes. immediately after harvesting

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Monsoon and Postmonsoon (July-January)

Spraying of the crop with 0.08 percent dimethoate or 1.0 percent Malathion after detrashing 1. Collection of adult beetles through light trap 2. Picking of grubs manually from field. 3. Collection and destruction of adult beetles from host trees immediately after first heavy summer rains Spraying the crop with demecron (0.1%)/ monocroptophos/ dimethoate (0.04%) Spraying the crop with Kelthane (0.1%)/ chlorfenvin/ monocroptophos (0.4%) Field release of Trichogramma chilonis adults@ 50,000/ha or 3.5 cc. parasitized Corcoran eggs/ha at fortnightly intervals regularly from the start of borer activity until a month before harvest Detrashing the crop from August through October at monthly intervals


Lectures: 12-14 (INSECT PESTS OF COTTON) 12. Major insect pests of cotton-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of spotted bollworm, pink bollworm, gram caterpillar and tobacco caterpillar. 13. Major insect pests of cotton-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of leafhoppers and whiteflies. 14. Minor insect pests of cotton-nature and symptoms of damage and management strategies at aphids, thrips, red cotton bug, dusky cotton bug, leaf roller, stem weevil, grasshopper and mealybug-IPM practices in cotton. Cotton is an important fiber crop grown in India. The hybrid varieties of cotton have high qualities when compared to old cotton varieties. The cotton crop in its early stage of crop growth is generally subjected to the attack of sucking pests from flowering till harvest; the boll worms cause appreciable damage. The losses in cotton from insect attack affect both yield and quality of the lint. The cotton insect pests can be chiefly divided into three groups viz., bollworms,

sucking pests and other insect pests. Bollworms Sucking pests Other insect pests Spotted bollworm Cotton aphids Red cotton bug American bollworm Jassids (leaf hoppers) Dusky cotton bug Pink bollworm whiteflies Cotton leaf roller Tobacco caterpillar Thrips Stem weevil Mealy bugs Grass hoppers Mites Insect Pests of National Significance: American bollworm (Helicoverpa armigera) Whitefly (Bemisia tabaci) – Vector for CLCuV(cotton leaf curl virus) Jassid (Amrasca bigutella bigutella) Tobacco caterpillar (Spodoptera litura) Spotted bollworm (Earias vittella) Thrips (Thrips tabaci) Pink bollworm (Pectinophora gossypiella) Insect Pests of Regional Significance: Termites (Odentotermes obesus) Haryana , Punjab, M.P, Gujarat and Rajasthan Aphid (Aphis gossypii) A.P., Karnataka, TN, Maharashtra, M.P., Gujarat Spiny Bollworm (Earias insulana) Punjab, Haryana, Rajasthan, Maharashtra Shoot weevil (Alcidodea affaber) Tamil Nadu , Karnataka , Gujarat Stem Weevil (Pemphras stimis) Tamil Nadu (Source: Ministry of Agriculture, Department of Agriculture & Cooperation, Directorate of Plant Protection, Quarantine & Storage, Government of India, 2003-04)

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A. BOLLWORMS 1. SPOTTED BOLLWORM / SPINY BOLLWORM (Matchala purugu) Earias vittella (Fabricius) Noctuiciae: Lepidoptera Earias insulana (Boisduval) Noctuiciae: Lepidoptera Distribution: • Earias vittella and E. insulana are serious pests of cotton. • These insects are very widely distributed. • Earias vittella is common in South East Asia. E. insulana is found in west Asia and north Africa.


Host range: • These pests attack a number of other plants of the family Malvaceae among which bhendi (Abelmoschus esculentus) is of great economic importance. Marks of identification:

Earias vittella: adult has pale with appear wings with a broad greenish band in the middle.

Earias insulana: The adult was completely green appear wings. The body length is about 1 cm while the wing span is about 2.5 cm. The caterpillars of both species are brownish white and have dark lead and a prothoracic shield. They have a number of black and brown spots on the body and hence the name spotted boll worm. Full grown larvae are stout and spindle shaped bearing a number of setae on each segment, and hence the name spiny bollworm. • A full fed larva measures about 19 mm in length. Nature and Symptoms of damage: • Insect first appears on the crop about 6 weeks after sowing. • Neonate larva cause damage to the terminal bud of the vegetative shoot or channel downwards or into the auxiliary nodes during early stage of the crop. The whole apex of the main stem collapses, if the main stem growing point is affected. • The larvae initially damage the tender shoots by boring into them, resulting in "drying of central shoots / drooping of central shoots" which withers and drops down. • In the later stages, larvae bore into the flower buds, squares and bolls. • The larva inserts its head inside the boll and feeds by filling the boll with excreta. A larva may move out and feed on another bud or boll. • Symptoms: bored flower buds (squares), bored bolls with larval frauss at the entrance of holes, premature dropping of affected bolls and premature opening of damaged bolls, which remain on plants. • The larval feeding results in early shedding of the bolls. • Presence of badly damaged tissues included lint and seed in damaged bolls.

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Life history: • The moth lay spherical, sculptured bluish green eggs singly scattered over fresh leaves, fresh squares, (flower buds), flowers. On an average each female moth lays 60-80 eggs. Egg stage is about 2-10 days. • The just hatched larva roams about on the plant surface for a very short period and then begins to bore into the plant tissue. They have a number of black and brown spots on the body and hence the name spotted boll worm. Full grown larvae are stout and spindle shaped bearing a number of setae on each segment, and hence the name spiny bollworm. • Larvae are light brown, tinged with grey to green. • The larval stage lasts for about 9-25 days. • Pupation takes place generally in fallen material, on plant surfaces and in cracks and crevices of the soil. Before pupation however, the larva spins a dirty, white silken cocoon of boat shaped one. Pupation period is about 6-25 days. • The duration of the various stages varies within very wide limits, depending on temperature and humidity of environment. • Adult longevity varies from less than a week to more than two months. • Total life cycle is about 1-2 months.

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Seasonal dynamics: • E. vittella seasonal mean damage in the rain fed cotton has reached >10% during 2005, being the highest during last 5 years. • E. vittella co-exist with Helicoverpa armigera. Management: • Deep ploughing. • Clean cultivation (timely crop termination, destruction of crop residues and cotton stalks) • Pre-planting cleanup measures during off-season (cleaning bunds, to remove alternate hosts etc.) • Grow bt cotton. • Practices that attract bollworms, such as closer spacing, more vegetative growth, excessive nitrogen application, excessive systemic insecticide application at early stage should be voided. • Grow trap crop like bhendi. • Arrange bird perches @ 10/acre. • Pheromone traps @ 2/ha attracts males, and lures can be changed for 40 days. • Mechanical collection and destruction of infested material. Infected shoots, squares and bolls, fallen plant material can be collected and burnt. • During September and October months, this bollworm combines with helicoverpa, causing heavy boll shedding, and hence control measures should be initiated at the stage. • Mechanical collection and destruction of larva is highly recommended than insecticide spray when the damage is less than 10%.


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2. AMERICAN BOLLWORM / COTTON BOLLWORM (Patcha purugu) (Kaaya toluchu purugu) Helicoverpa armigera (Hubner) Noctuiidae:Lepidoptera • The Cotton Bollworm, American bollworm, Corn Earworm, Tobacco Budworm or Old World Bollworm (Helicoverpa armigera) known to feed on a wide array of plants including a range of plants cultivated by humans. • They are the major pest in cotton, the most polyphagous and cosmopolitan pests. • The cotton bollworm feeds on a wide range of crops including corn, cotton, alfalfa, bean, grain sorghum, lettuce, peanuts, pecan, pepper, tobacco and tomatoes. • Cotton bollworm also feeds on a wide range of non-cultivated crops depending on geography. • Because of its wide host range, it is known by several common names including corn earworm and tomato fruitworm. • This moth is a major pest threat because the larva can feed on a wide range of economically important crops including cotton, corn, tomato, legumes and tobacco. • In addition to feeding on high value crops the old world bollworm is an extremely dangerous pest because: 1) it is extremely fecund, 2) it can sustain itself on over 180 different plant species, 3) it can undergo diapause during adverse conditions and 4) it can migrate over long distances. • To make matters worse, the bollworm has evolved a high degree of resistance to organophosphate and pyrethroid insecticides. Marks of identification: Adult: The adult moth is described as a typical Noctuid. The stout bodied / heavy bodied moth has a wing span range of 35-40 mm and the body length range of 18-19 mm. Forewings dark yellow grey or brown with a dark cross band near outer margin and dark spots near costal margins (center of forewings), and are relatively smaller than hindwings. The coloration varies from dull greenish yellow to olive gray or light brown and females are darker than males. Revised during 2011

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Trichogramma evanescens parasitises the eggs of spotted boll worms. Release Trichogramma @ 20,000/acre. Release chrysoperla predator @ 4000/acre. Bracon lefroyi, Bracon greeni, Bracon hebetor, Bracon brevicornis, Apanteles sp and Elasmus sp parasitise the larval stage of this pest. The pupae of this pest are parasitised by Chelonus and Chalcis species. Spray bt formulations @ 2gm/L or 5% NSKE in synchrony with early larval instars. Recommended insecticides: Methomyl 25EC (2L/ha), Thiodicarb 75WP (2kg/ha), Acephate 75WP (780g/ha), chlorpyriphos 20EC (1250ml/ha), profenophos 50EC (1500ml/ha), quinalphos 250EC (2L/ha), triazophos 40EC (1.5L/ha), novaluron 10EC (1L/ha), buprofezin 25EC (400ml/ha), indoxacarb 15EC (500ml/ha), spinosad 48EC (100ml/ha), ememectin benzoate 5EC (200ml/ha) Spray pesticides like endosulfan and chlorpyriphos with sesamum oil (synergist). Two precautions are necessary to ensure success 1) the insecticidal application should be so timed as to coincide with the peak of the hatching of eggs, so that the just hatched larvae may get the fatal dose before entering the plant tissue. 2) The parasite activity in the field should be carefully assessed before the insecticidal application.

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Eggs: The eggs are spheres approximately 5 mm in size, which are initially white in coloration, then darken to grayish brown prior to eclosion. The eggs are sculptured with vertical ridges of alternating length, which surround a smooth apical area that contains the micropyle. Eggs are laid singly on the reproductive structures of plants. Larvae: First instar larvae are cream to white with a dark head, with a spotted appearance due to sclerotized setae, tubercle bases and spiracles on body. Larva relatively smooth (hairless). Larval color darkens with successive molts for the 6 instar stages (typical), and coloration can vary considerably (yellow, brown, red or cream) due to diet content. The caterpillars are greenish with darker broken lines along the side of the body. Head capsule of older larvae dark yellow or orange.

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• Typically, larvae move down the plant as they mature. • Preferred feeding sites include flowers, buds, bolls and leaves. Life cycle: • Adult female lays sphere shape eggs, singly, on the reproductive structures of plants and incubate for approximately 3-14 days depending on temperature. • First instar larvae are cream to white with a dark head, with a spotted appearance due to sclerotized setae, tubercle bases and spiracles on body. Larva relatively smooth (hairless). Larval color darkens with successive molts for the 6 instar stages (typical), and coloration can vary considerably (yellow, brown, red or cream) due to diet content. The number of larval instars and the duration of the larval period will fluctuate depending on the host plant and the temperature. Typically there are 5-7 instars and a larva period of 12-32 days before pupation occurs.

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Symptoms of damage: • Newly hatched larva eats the egg sheath and then wanders in search of a good site to feed. • Young larva feed on leaves, squares, bolls, flowers and in terminals. • Small larvae feeding on leaf tissue may result in pinhole damage. • Older larvae can destroy squares and bolls. • Feeding on squares results in "flared or open" squares. • On the boll, the larva can be seen feeding by inserting head and half of the body inside the boll. • Feeding on bolls results in boll shedding and premature opening. • One larva may destroy one terminal and 6 to 8 bolls before pupating.


Seasonal incidence & factors of abundance: • Minimum temperature and evening relative humidity exhibited highly significant negative correlation with the gram pod borer population. • The larval populations started increasing and reached its maximum of 12.97 mean larval population/plant during 4th week of March (12th standard week). • The population has significantly positive correlation with both minimum and maximum temperature and the correlation coefficient being 0.71 and 0.82, respectively. Management: • Deep ploughing. • Grow bt cotton. • Crop rotation with other non-host plants (breaks life cycle, increases natural enemies population). • Intercropping with greengram, blackgram, cowpea etc. • Trap crops (marigold) for monitoring egg laying, and also killing the neonates. • Use pheromone (helilure) traps @ 4/acre for pest monitoring, forecasting & trapping males. • Light traps @ 1trap/5acres, to monitor the pest population, and also killing. • Arrange bird perches @ 10/acre. • Release Trichogramma egg parasitoids @ 20,000/acre at an interval of 3-4 weeks. • Release of Chrysoperla predators @ 4000/acre. • Topping of cotton plants during November-December, when maximum egg laying is noticed, to remove eggs. • Spray HelioNPV @ 500LE/ha or Bt formulations @ 2gm/L, 5% NSKE in synchrony with early larval instars. • Mechanical collection and destruction of larva is highly recommended, when larva grows big. Revised during 2011

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Pupation occurs in the ground (earthen cell). The pre-pupal stage will last for 1-4 days. The pupal period will take 10-14 days if the bollworm is not in diapause. If in diapause, the pupal period can take several months to complete.

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Do not use the same pesticide, repeatedly. Spray endosulfan / quinalphos / chlorpyriphos / triazophos / acephate / fenvalerate / cypermethrin, if overlapping populations present. Spray pesticides like endosulfan and chlorpyriphos with sesamum oil (synergist). Two precautions are necessary to ensure success 1) the insecticidal application should be so timed as to coincide with the peak of the hatching of eggs, so that the just hatched larvae may get the fatal dose before entering the plant tissue. 2) The parasite activity in the field should be carefully assessed before the insecticidal application.

3. PINK BOLL WORM (Gulabi matchala purugu) Pectinophora gossypiella (Saunders) Gelechiidae:Lepidoptera The pink bollworm is native to Asia but has become an invasive species in most of the world's cotton-growing regions. • The pink bollworm is a very widely distributed and probably the most serious cotton pest on a world basis. • The American cottons in India are damaged much more by the pink bollworm than the indigenous varieties. • The pink bollworm infests cotton, mesta, Abutilon indicum, Althaea rosea and Bhendi. Marks of identification: • The pink bollworm is not pink in its earlier stages and in the later stages, it is distinctly pink colour. • Moth is small about 5-6 mm in length and has wing span of 12.5 mm. Body is dark brown in colour with numerous small black spots on the wings. The first segment of the antenna bears 5-6 long stiff hairs and the palpi are pointed and curved upwards. The adult is a small thin gray moth with fringed wings. • The larva is a dull white eight-legged caterpillar with conspicuous pink banding along its dorsum. The larva reaches one half inch in length. •

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Nature & symptoms of damage: • The first brood during cotton season develops mainly on buds & flowers. In infested squares, before flower opening, the larvae spins a web around the tips of the petals, and prevent flower opening and thereby protects itself from hot sun and enemies. • During the flowering stage, the larva enters inside the flowers and ties the tips with silken threads and feeds inside and is known as "Rosette flowers (improper opening of flowers)”. • The larvae feed on developing anthers & style, and occasionally on the ovary. Attacked small buds/flowers drop prematurely, while large buds develop with poorer quality kapas.


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Life cycle: • The moths are active during night and lay flattish scale like whitish eggs singly on various parts of young shoots. However, half developed bolls are preferred when available. • The larva is a dull white eight-legged caterpillar with conspicuous pink banding along its dorsum. The larva reaches one half inch in length. The larvae emerge from the eggs, and inflict damage through feeding. In 25-30 days it is full grown, has a uniform pinkish colour and is about ½” in length. The larva period usually 3 months. Larval diapause is common in the pest. Revised during 2011

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The pink boll worm larvae do most spectacular damage to practically mature cotton bolls which they enter at such a tiny stage of just hatched larvae that their entry holes get healed and in which they remain devouring both seed and fiber forming tissues. The infestation at times is so severe that up to 10 larvae are found in each boll and 75100 per cent bolls are found infested. On boll formation, the larva enters/bores into the boll mostly from the top of growing boll and remains inside with “no external visible damage". The larva bores into the boll mostly from the top. Inside the boll, the larvae feeds on lint, seed affecting the lint quality and germination of the seed. They chew through the cotton lint to feed on the seeds. The seeds are destroyed The lint development is retarded and is weakened. It causes premature opening of the boll. Invasion of saprophytic fungus stain the lint both in the gin and in the boll. Infestation lowers germination capacity of unattacked in the attacked boll. The ginning percentage and quality of the lint is greatly reduced.

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Management: • Large scale destruction of the resting stages of the larvae in the double seeds of cotton • Two types of larvae are found in a mixed population; (1) one type pupates in normal manner, while the other type makes preparations for prolonged hibernation, (2) The larva scopes and binds together around itself generally two but at times more than two seeds with the help of its self-produced silk and then enters the resting stage in the hybernaculum prepared between these double seed and lined with silk (this resting stage, in double seeds is very largely responsible for the seriousness of the pest). • The destruction can be brought about by fumigation or heat treatment of cotton seed. • Seed Fumigation with methyl bromide at 1.5 kg/100 cu.mt or with phostoxin at 200 tablets/100 cu.mt for 24 hours, may be quite effective. • Heat treatment for a few minutes to the permissible limit of 140°C before sowing or even by exposing it to hot sun. • Removal of the cotton stalks/stubbles soon after harvest or at any time much earlier than the sowing of the next cotton crop. • Since the eggs are protected mostly by calyx and the newly hatched larva immediately bore into developing boll, it is difficult to manage this pest with insecticides. Therefore, hygienic conditions are more important than chemical methods. • Avoid staggered sowing. • Avoid ratooning or summer crop. • Use acid-delinted seed only. • Grow bt cotton. • Grow trap crops like bhendi. • Monitor the pest with pheromone traps (Gossyplure) • Collection and destruction of infested flowers, buds etc along with infested shoot. Destroy pink bollworm larvae in rosette flowers, and also through periodical removal of dropped squares, dried flowers, pre-matures bolls. • Periodical spraying with carbaryl or methyl parathion may be done as done. • Allow cattle or goats / sheep to graze upon green bolls, and attacked bolls after final picking to prevent carry-over of the pest to next season. • Restrict movement of cotton seed from one area to other. • Ginning mills to burn the stained lint regularly. Revised during 2011

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Pupation in flimsy cocoon in boll, often in seed. The pupation period lasts for about 620 days depending on the season.

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4. TOBACCO CATERPILLAR (Pogaku ladde purugu) Spodoptera litura (Fabricius) Noctuidae:Lepidoptera It is also known as the Cluster caterpillar, Cotton leafworm, Tobacco cutworm, and Tropical armyworm. • It is found throughout the tropical and sub-tropical parts of the world. • They are International Pests. • Wide spread in India. • Besides tobacco, feeds on cotton, castor, groundnut tomato, cabbage and various other cruciferous crops. Marks of identification: • Moths are medium sized and stout bodied with forewings pale grey to dark brown in colour having wavy white markings and whitish hind wings. • The female lays eggs in masses and covers them with hair scales from her body (anal tuft hairs). • Larvae are variable in colour starting pale green and turning dark green to brown. Caterpillar is velvety black with yellowish green dorsal stripes and lateral white bands. A dark rings like structure is seen on anterior and posterior region in early stages. •

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Life cycle: • Pest breeds throughout the year. • Moths are active at night. • Female lays about 300 eggs in clusters. • The eggs are covered over by brown hairs and they hatch in about 3-5 days. • Larvae feed gregariously for first few days and then disperse to feed individually.

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Nature & symptoms of damage: • They are chiefly defoliators. • The early instars are gregarious and scrape the chlorophyll content of leaf lamina giving it a papery white appearance (jalledaaku). Larvae feed gregariously for first few days and then disperse to feed individually. • Later irregular holes are made on the leaves. • During later instars, they skeletonize the leaves leaving only veins and petioles. • During flowering and boll formation stage, the caterpillars also feed on the internal contents of bolls and cause irregular holes.


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Pass through 6 instars. Larval stage 15-30 days. Pupation inside the soil, pupal stage 7-15 days. Adults live for 7-10 days. Total life cycle 32-60 days. 8 generations in a year.

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B. SUCKING PESTS 1. COTTON APHID (Peenu Banka) Aphis gossypii Glover Aphididae: Hemiptera • Cotton aphid is of worldwide distribution. • In India, it is widely distributed. • It is a polyphagous species. However on cotton, often it causes appreciable damage to the crop. Marks of identification: • The cotton aphid is small, soft, yellowish, green or greenish brown in colour. • It is found in colonies of hundreds on the tender shoot and the under surface of tender leaves. • They are characterized by the presence of a pair of cornicles on the 8th segment of abdomen used to exude honeydew and wax. • Aphid colonies are commonly visited by ants which feed on the honeydew secreted by the aphids. This honeydew also serves as food on which the sooty mold grows. • They are wingless normally but winged forms are often found mostly in the beginning and towards the end of season. Wings are thin, transparent and are held like a root over the body. When populations on the host plant are high, winged forms are produced, and these fly to adjacent plants to establish new colonies. • Nymphs are light yellowish green or brownish or greenish black in colour and colonies on the growing points, lower surface of leaves and tender shots.

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Management: • Management practices are same as other bollworms. • Trap crop: castor • Use/spray SLNPV @ 500LE/ha. • The larvae develops very thick skin once in third instar, and it becomes very difficult to manage the pest even with high dose of insecticides, and hence, it is always better to follow practices like collection & destruction of egg masses and neonate larval groups, erection of bird perches etc. • Now a days, in case of heavy infestation of the pest, farmers prepare a poison bait (rice bran+jaggery+insecticide @ 5kg+0.5kg+0.5kg carbaryl or 50ml methomyl) and prepare in small balls, and spray/spread in the field, since the larvae are active during night time (due to this reason, they escape the insecticide spray). • Use pheromone traps with Litlure.


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Life cycle: • The female aphids are both alate and apterous. • Female reproduces both parthenogenetically and viviparously. • There are four instars. • Egg period is about 3-5 days. • Nymphal period is about 7-9 days. • Brinjal, chilies, amaranths etc., are other host plants of this pest. Management: • Seed treatment with imidacloprid 70WS (Confidor) @ 5g/kg seeed for non-hybrids, 10g/kg seed for hybrids, or thiamethaxam 25WG (Actara) @ 5g/kg seed or carbosulfan 25DS (Marshall) @ 50g/kg seed for all early sucking pests. • Intercropping with soybean / cowpea / groundnut / greengram / blackgram @ 1:2 ratio to colonize the predators such as ladybird beetles, syrphids and chrysopids. • Stem application with monocrotophos/methyl demeton 1:4 or imidacloprid 200SL in 1:20 dilution with water at 20, 40, 60 DAS. • Spray 5% NSKE. • Need based, judicious and safe application of pesticides are the most vital tripartite segments of chemical control measures under the ambit of IPM. • Spraying of monocrotophos 1.5ml/lt or methyl demeton 2ml/lt or imidacloprid 0.2ml/lt or acetamiprid 0.1g/lt or thiomethoxam0.2g/lt or acephate1.5g/lt or triazophos 1.5ml/lt.

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Nature & symptoms of damage: • Aphids feed by sucking sap from their hosts. The undersides of leaves are preferred, other leaf surfaces and flower buds are its next choice, but the entire host may be covered when populations are large. • Infested leaves often become cupped downwards and may appear wrinkled. • Heavy infestations on some hosts may result in wilting. • Young plants may have reduced or stunted growth. • Like other soft bodied insects such as leafhoppers, mealybugs, and soft scales, aphids produce honeydew. Copious amounts of honeydew, sweet and watery excrement, may be produced. Honeydew serves as a medium on which sooty mold grows. Sooty mold blackens the leaf and decreases photosynthetic activity. • The cotton aphid is a virus vector and has a wide host range including many vegetable crops (Papaya Ringspot Virus, Watermelon Mosaic Virus, Cucumber Mosaic Virus). • Both apterae (wingless) and alate (winged) aphids are able to transmit viruses.


2. LEAF HOPPERS / JASSIDS (Patcha doma) Amrasca biguttula biguttula (Ishida) Cicadellidae: Hemiptera • The cotton jassid has been posing a very serious problem to cotton growers in India ever since the introduction of exotic varieties of this crop. • The jassids are popularly known as leafhoppers, particularly because their activities are mostly confined to the leaf surface. • These insects are active at night and are attracted to light in very large numbers. • The pest has a number of alternate hosts mostly belonging to the families’ malvaceae and solanaceae. Marks of identification: • A. biguttula biguttula is a small insect, the various nymphal stages of which vary from less than 1 mm to about 3 mm. • Its adult stage is subjected to seasonal changes in colour. It is reddish in winter and greenish yellow in summer. • The adult is a wedge shaped insect about 3.5 mm in length. • There is a black spot on each forewing and the black spots on the vertex. • Eggs are inserted in the leaf tissues on the upper leaf surface. • Nymphs are also pale greenish in colour like the adults but are wingless and are found in large numbers on lower surface of leaves. • Both and nymphs and adults walk diagonally.

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Nature & symptoms of damage: • Both nymphs and adults inflect the same type of damage. • They suck up the cell sap from the plant tissue. • Moreover, it is also believed that during the process of “desapping” the plant, they also inject a toxin into the plant tissue, resulting into Hopper burn. • In susceptible varieties, the jassid attack results in general mottling accompanied by the curling of the entire lamina with brown necrotic patches. • Thus, the entire photosynthetic activity of the plant is very seriously interfered with. • In case of severe infestation, plants become stunted and dry. • Attacked leaves curl up and roll.


Life cycle: • The cotton jassid lays about 30 eggs. The eggs are usually inserted full length into the spongy parenchymatous tissue between the vascular bundles and the epidermis. The eggs hatch in 4-11 days. • The nymph moult five times and the nymphal period last for 7-21 days. • The whole life cycle is completed in a period which varies from about two weeks to more than a month and a half, depending on environmental conditions. • There are 8-10 overlapping generations. Management: • Resistant varieties: MCU-5, Narasimha. • Seed treatment with imidacloprid 70WS (Confidor) @ 5g/kg seeed for non-hybrids, 10g/kg seed for hybrids, or thiamethaxam 25WG (Actara) @ 5g/kg seed or carbosulfan 25DS (Marshall) @ 50g/kg seed for all early sucking pests. • Intercropping with soybean / cowpea / groundnut / greengram / blackgram @ 1:2 ratio to colonize the predators such as ladybird beetles, syrphids and chrysopids. • Stem application with monocrotophos/methyl demeton 1:4 or imidacloprid 200SL in 1:20 dilution with water at 20, 40, 60 DAS. • Spray 5% NSKE • Need based, judicious and safe application of pesticides are the most vital tripartite segments of chemical control measures under the ambit of IPM. • Spraying of monocrotophos 1.5ml/lt or methyl demeton 2ml/lt or imidacloprid 200SL 0.2ml/lt or acetamiprid 0.1g/lt or thiomethoxam0.2g/lt or acephate1.5g/lt or triazophos 1.5ml/lt. 3. WHITEFLY (Tella doma) Bemisia tobaci (Gennadius) Aleyrodidae: Hemiptera • The cotton white fly is known to infest about 50 different species of plants but it becomes quite a serious pest of cotton in certain regions of the country. • Among the cultivated crops, it attacks cotton, radish, watermelon, cucumber, chillies, brinjal, tomato, potato, tobacco etc. Marks of identification: • The adult is minute insect measuring about 0.5 mm in length having white or grayish wings, a yellowish body and red medially constructed eyes. • Nymphs are oval shaped, scale like, blackish with marginal bristle like fringes. • The nymphs remain stationary once they settle down.

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Nature & symptoms of damage: • The infestation by this pest adversely affects the physiology of the cotton plant at all its stages of growth. • Both adults and nymphs cause severe damage. • The nymphs and adults suck the cell sap and lower the vitality of the plant.


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Normal photosynthetic activity gets affected due to the growth of sooty mould on the honeydew excreted by the insect. The vegetative growth is retarded and boll formation is seriously hampered. Also the shedding of the bolls is accentuated and proper opening of the bolls is interfered with. Besides inflecting this direct damage, the pest produces honey dew which spreads on the leaf and leads to sooty mould development and adversely affects photosynthesis. Both the quantity and quality of cotton suffers due to white fly infestation. The infested leaf gives black blotted appearance. It is vector of leaf curl virus.

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Seasonal occurrence & factors of abundance: • The maximum infestation on cotton occurs during July. • High temperature and low humidity are reported to be conducive to the multiplication of this pest. Management: • Grow resistant cultivars: LK-861, LPS-141, L-389, L-604, Supriya, Kanchana. • Seed treatment with imidacloprid 70WS (Confidor) @ 5g/kg seeed for non-hybrids, 10g/kg seed for hybrids, or thiamethaxam 25WG (Actara) @ 5g/kg seed or carbosulfan 25DS (Marshall) @ 50g/kg seed for all early sucking pests. • Intercropping with soybean / cowpea / groundnut / greengram / blackgram @ 1:2 ratio to colonize the predators such as ladybird beetles, syrphids and chrysopids. • Stem application with monocrotophos/methyl demeton 1:4 or imidacloprid 200SL in 1:20 dilution with water at 20, 40, 60 DAS. • Keep yellow pan / sticky traps @ 25 traps/ha, for both monitoring and also mass trapping. • Locally available empty yellow palmoline tins coated with grease / vaseline / castor oil on outer surface may also be used.

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Life cycle: • A single female of this species lays about 70 eggs on the undersurface of leaves, mostly on the top and middle leaves of plant. Eggs are laid singly. Egg period ranges from 3-33 days. The insect can often breed parthenogenitically. The eggs are stalked and light yellow in the beginning but turn brown later on. • Nymphs moult thrice. Nymphal period lasts for 9-18 days. • There are about a dozen over lapping generations in a year.


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Spray NSKE 5%. A chaliced parasite attacks the older nymphs and the parasitization is at times more than 30%. Also, there are a few predators like some species of Chrysopa and coccinellids, which feed on the whitefly stages. Need based, judicious and safe application of pesticides are the most vital tripartite segments of chemical control measures under the ambit of IPM. Spraying of monocrotophos 1.5ml/lt or methyl demeton 2ml/lt or imidacloprid 200SL 0.2ml/lt or acetamiprid 0.1g/lt or thiomethoxam 0.2g/lt or acephate 1.5g/lt or triazophos 1.5 ml/lt.

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5. COTTON MEALY BUG Phenacoccus solenopsis Psuedococcidae:Homoptera • During the last few years, mealy bug has become a major problem in several crops such as cotton, vegetables and fruits. • Several states such as Punjab, Rajasthan, Maharashtra and Gujarat have faced serious infestation of mealy bug in cotton. • To manage this menace, an awareness campaign in Punjab has been initiated by Ministry of Agriculture in a project mode. • Mealy bug are polyphagous and multiply on different hosts. • Initially the pest breeds on weeds and later migrates to cotton crop. Parthenium is a favourite host for the pest. It also feeds on Itsit, datura, milkweed, Chenopodium sp. It multiplies well on okra, tomato and brinjal. • Reproduction in mealy bug is mostly parthenogenetic. • Mature female lays eggs in ovisacs. Each ovisac contains 150- 600 eggs, majority of which are female. • Eggs hatch in 3 to 9 days into nymphs called ‘crawlers’, which are very mobile. The nymphal stage lasts for 22-25 days. • Individual mealy bug take 25- 30 days to grow into adults under normal conditions. • There are 12- 15 generations in a year. • The species survives cold conditions as eggs in ovisac or other stages, both on the host plant or in the soil. In warm climates, the insects remain active and reproduce round the year. • Adults and nymphs weaken the plants by sucking sap from leaves, twigs, stems, roots and fruiting bodies.

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4. COTTON THRIPS (Taamara purugu) Thrips tabaci Thripidae : Thysanoptera Scirtothrips dorsalis Thripidae : Thysanoptera • Cotton thrips is a highly cosmopolitan form and is found on all kinds of vegetation. • Onion and garlic, Amaranths, guava, solanacious and cucurbitaceous plants, groundnut, chilies, mango, cabbage, bhendi etc., are other host plants. • Nymphs and adults suck sap from leaves and flower buds. • Eggs are laid inside the tissues of leaves and shoots. • Nymphs are tiny slender, fragile and yellowish straw in color adults resemble nymphs with heavily fringed wings. • Margins of affected leaves get slightly curled up and the leaf blades show uneven surface, when attack occurs in flowering stage, the affected flowers may wither away. • It is vector of yellow spot virus and spotted wilt virus.


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Bolls are deformed, fewer and smaller in size in affected plants. Honey dew secreted by the pest encourages development of black sooty mould which adversely affecting photosynthetic activity.

Management: Refer to aphids / jassids / whiteflies.

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6. RED SPIDER MITES (Erra Nalli) Tetranychus telaries Tetranychidae : Acarina Tetranychus bioculatus Tetranychidae : Acarina Polyphagotarsonemus latus Tetranychidae : Acarina Eriophyes gossypii Tetranychidae : Acarina • The mite is a polyphagous and is known to feed on 183 species of plants including cucurbits, brinjal and bhendi on which it is sometimes very serious. Marks of identification: • Mites are tiny, transparent and found mostly under the lower side of leaves. • Nymph is light brown in colour and has two eye spots. • Four pairs of legs and quite active. • Adult female body is oval and is variable in colour, red, green amber or rusty green and with two large pigmented spots on the body. • Tetranychus telaries mite is also called as two spotted spider mite worldwide.


Nature & Symptoms of damage: • Both nymphs and adults cause damage. • Large numbers of webs are formed. • Spider mites feed on the lower surface of the leaf underneath a web. • On a close examination of the lower leaf surface, mites smaller than a pinpoint may be seen. • The infested leaves rapidly curl up, become hard and crisp and ultimately shed. • Bolls ripen prematurely and in serious infestation shed. Life cycle: • It is active from March-October and passes winter as gravid female, lays 60-80 eggs. Egg period 2-6 days larvae. • Feed underneath webs within 3-4 days change to nymphs, which have four pairs of legs. Nymphs grow to maturity in 2 stages within 4-9 days and adults live for 9-11 days. • Total life cycle in active period takes 9-19 days. Seasonal incidence & factors of abundance: • Mite infestation begins in the seedling stage and extends to harvest. • The large scale use of chlorinated hydrocarbon insecticides for the control of other pests leads to the multiplication of the mites as these are less toxic to mites but they kill their natural enemies in large number. • Spray acaricide like dicofol 18.5EC (2.7ml/L) / wettable sulphur 75WP (2g/L), dimethoate @ 0.03%, or phosalone @ 0.07%.

Some times cannibalism exists in this insect. The reduvid bug Harpactor costalis is predacious on red cotton bugs. Dusting BHC or DDT 5% or folidol 2% dusts is effective against this pest. Revised during 2011

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C. OTHER INSECT PESTS 1. RED COTTON BUG Dysdercus cingulatus Pyrrhocoridae: Hemiptera • In India, the bug infests cotton in all cotton growing regions. • Bhendi, maize, mesta etc., are other host plants • Both nymphs and adults are medium sized, reddish with white bands on the abdomen and black markings on wings. • The nymphs and adults suck sap from tender parts of the plants like leaves, petioles and shoots in early stages and then infest flower buds and immature bolls and infest bolls that have just opened. • Plants lose their vigor and bolls open prematurely (badly) with stained lint. • Infested seeds get shriveled, under developed become unfit for sowing and oil content gets reduced. • From the spot of injury on the bolls, a bacterium; Nematospora gossypii gains entrance and spoils the lint.


2. DUSKY COTTON BUG Oxycarenus laetus Lygacidae : Hemiptera • In India it is found in all cotton regions. • Adults are dusky, greyish brown bug with pointed head and white hyaline wings. • Both nymphs and adults suck sap from immature seeds and strain the lint. • The seeds do not ripen and get damaged. • Seeds get lighter weight and lose their germination capacity.

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The anthocroeid bug - Orius tantilus is predaceous on the nymphs. Dusting BHC or DDT 5% dust may be effective.

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Eggs are laid singly on undersurface of the leaves. Caterpillars are bright green in color with dark brown head. The larva rolls the leaf and feeds on the green tissue in the early stage and eats up a large portion of the leaf as it grows. Severe attack results in the presence of a large number of leaf rolls and the plants become stunted, ultimately. Pupation takes place within the leaf roll. The natural enemies of the insect which are parasitic on its larvae are, Brachymeria bengalinsis pulchellae (Chalcididae), Elasmus indicus (Elasmidae), Apanteles spp. Bracon lefroyi, Microbracon recinicola (Braconidae) and Trichospilus pupivola (Eulophidae) etc. Egg is parasitised by Trichogramma sps and pupa by Xanthopimpla spp. Spraying with methyl parathion at 0.025% or Carbaryl at 0.15% or monocrotophos at 0.03% controls the pest effectively.

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3. COTTON LEAF ROLLER (Aaaku chuttu purugu) Sylepta derogata Pyralidae : Lepidoptera • Cotton leaf roller has distribution in Africa, Australia, Burma, Srilanka, China, India, Japan etc. • Cotton, bhendi and several other malvaceous are host plants. • It is primarily a sporadic pest of cotton in India. • Adult is a medium sized moth with yellowish wings having brown wavy markings.


4. COTTON STEM WEEVIL Pempherulus affinis Curculionidae: Coleoptera • Cotton stem weevil is a serious pest of cotton and is known from India, Burma, Thailand and Philippines. • This pest is a serious one of Cambodia cotton, particularly on summer crop. • Adults generally feed on the bark of plants. • Grub bores into the stem above the ground level and makes tunnels. • Attacked plants show characteristic gall like swellings on the stem. • In severe cases causes mortality of plant during early stage of crop growth. • Infestation starts on 12-15 days old cotton plants. • Some of the hymenopterous chalacidids and braconids are parasitic on the grubs of cotton stem weevil. But parasitism in the fields is found very low. • Removal and destruction of attacked plants. • Spray endosulfan 0.05% at fortnightly intervals commencing three weeks after sowing. 5. COTTON GRASSHOPPERS Cyrtocanthacris ranacea Acrididae: Orthoptera Chrotogonus oxypterus Acrididae: Orthoptera • Cotton crop is often damaged in the early stage of these grasshoppers. • Both nymphs and adults feed on leaves. Heavy infestation results in complete defoliation of plants. • Eggs are laid in clusters in soil • Nymphs with broad yellowish stripes on the prothorax • Adult is stout and elongated. ETLs (Economic Threshold Levels): Based upon the result of survey / field scouting etc., the extension functionaries are to determine the ETLs for different pests to advice farmers to initiate pest management practices accordingly. The ETLs for major pests are as under:

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5 % damaged fruiting bodies or 1 larva per plant or total 3 damaged American & Spotted bollworm squares/ plant taken from 20 plants selected at random for counting. Pink bollworm 8 moths / trap / day for 3 consecutive days or 10% infested flowers or bolls with live larvae. Spodoptera 1 egg mass or skeletinized leaf / 10 plant. Jassids * 2 jassids or nymphs per leaf or appearance of second grade jassid injury. (yellowing in the margins of the leaves ) Whitefly * 5 – 10 nymphs or adults per leaf before 9 AM. Aphids 10 % affected plants counted randomly Thrips * 5 – 10 thrips / leaf *3 leaves (top, middle, bottom) per plants from 10 plants

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Integrated Pest Management Strategies for Cotton Insect Pests: Cultural Methods: • Summer deep ploughing to expose soil inhabiting / resting stages of insects, pathogen and nematode population. • Growing cotton after cotton should be avoided. Adopt proper crop rotation. • Select healthy seeds of resistant / tolerant varieties • Only certified seeds should be used. • Acid delinting treatment should be followed before sowing @ one litre commercial sulphuric acid for 10 kg. seeds. • Seed treatment with imidachloprid 70 WS * @ 5 g / kg of seed in case of non-hybrid variety and 10 g / kg in case of hybrid or Thiomethoxam 5 g / kg seed or carbosulfan 25 DS @ 50 gms / kg of seeds for early sucking pests. • Sowing should be done timely within 10 to 15 days in a village or block in the season. • Adopt proper spacing, irrigation and fertilizer management. • Avoid application of high nitrogenous fertilizers to boot the crop. • Use neem cake with oil content @ 5 quintal / ha in termite / nematode infested fields. • The crop should be maintained weed free for at least 8 – 9 weeks after sowing till canopy stars closing in by timely intercultivation. • Remove and destroy weeds as alternate hosts viz. Sida sp., Abutilon sp., Logascae mollis and other malvaceous plants in the cultivated area. • Growing intercrops/strip crops/barrier crops. • The following inter–cropping system is recommended for Central and South Zone to colonize the bioagents fauna such as lady bird beetles, chrysopa and syrphid flies : Cotton + Cowpea, Cotton + Soybean, Cotton + Groundnut, Cotton + Pulses ( Green gram / Black gram • Growing fodder jowar or maize as barrier crops around cotton and castor and marigold as trap crop was also found more advantageous to manage pests of cotton. • Use of trap crops like okra, Canabinus, castor, marigold (Tagets), bhendi, early Pigeon pea, coriander, jowar, maize crops is recommended. Insects feeding on these crops must be removed and destroyed. • Removal of cotton stubbles after last picking, without opting for ratoon crop. • Do not extend the normal crop period and avoid rationings. • Grazing by animals after last picking is recommended for checking the carry over population of bollworms. • Remove and make use of crop residues after last picking as FYM or in Paper Industry. • Staking the cotton stalks near the field should be avoided. Destroy opened bolls on the plant. • Crushing of cotton seeds should be completed by early April in North Zone. • Otherwise fumigate the seeds by the end of May under expert supervision. • Clean the gin thrashers for checking of carry over population of pink bollworm. • Install pink bollworm pheromone traps in the premises of ginning factories to trap emerging pink bollworm moths. Mechanical methods: • Hand picking and destruction of various insect stages, affected plant parts and rosetted flowers. • Clipping/nipping of terminal shoots at 90-110 DAS depending upon cultivars. • Collection of Spodoptera egg masses and putting them in perforated cage. • Monitoring pests by using sticky, pheromone and light traps.

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The adult monitoring should be supported by egg and larval monitoring following sequential sampling technique at frequent intervals in case of boll worm. • Bird perches should be arranged @ 10 to 20 per acre for encouraging bird predation on bollworm larvae. Biological methods: • Conservation of predators (lacewings, lady bird beetles, staphy linids, predatory wasps, surface bugs like Geocoris, Anthocorid, Nabids, Reduviids, Spiders, parasitoids like Apanteles, Bracon, Rogas, Agathis, Campoletis, Eriborus, Trichogramma, Telenomu by growing two rows of maize / sorghum or cowpea along the border. • Install 8-10 bird perches/ha for the benefit of predatory birds after 90 days of crop growth like black drango, king crow, orange Myna and Blue jay. • Observe the incidence of bollworms either by visual observation or by using pheromone @ 5 traps/ha. specific for each bollworm species. • Monitor the incidence of sucking pests and release eggs or first instar larvae of Chrysoperla @ 10,000 eggs / grubs / ha. • Release Trichogramma chilonis (cotton strain) immediately after the appearance of bollworm eggs (when moth activity is observed) @ 1,50,000/ - ha / week (2–3 releases) 40-50 days after sowing. • Avoid spraying with insecticides for at least one week before and after the release of biocontrol agents. • Apply Spodoptera NPV 250-500 LE/ha (1LE = 2X10 POBs) (1LE /lit of water) on observing 1st Instar larvae. • HNPV can be applied in the early infestation of Helicoverpa. Spray Ha NPV @ 500 LE/ha + 5 % jaggery water + 0.1% Boric acid (Spray during morning or evening hours) at 60-70 DAS. • Spray bt formulations (Dipel, Halt, Biobit, Delfin etc. @ 200-300 g ai/ha). • Entomopathogenic fungi such as Metarhizium anisopliae, Beauveria bassiana and Nomurea rileyi can be used against Helicoverpa. Chemical methods: • Need based, judicious and safe application of pesticides are the most vital tripartite segments of chemical control measures under the ambit of IPM. It involves developed IPM skills to play safe with environment by proper crop health monitoring, observing ETL and conserving natural biocontrol potential before deciding in favour of use of chemical pesticides as last resort. Therefore, it is necessary to rely upon pesticides as per the requirement. • Seed treatment with imidacloprid 70WS 5g/Kg or thiomethoxam 4g/Kg or carbosulfan 40-50g/Kg. Stem application with monocrotophos/methyl demeton 1:4 or imidacloprid 200SL in 1:20 dilution with water at 20, 40, 60 DAS. • Stem application with monocrotophos or imidacloprid at 1:4 or 1:20 dilution at 20,40 and 60 DAS was found effective in controlling the sucking pest like aphids, leafhoppers etc., in initial stages of crop growth. • Following suggestions have important bearings for the success of control measures in the context of IPM strategy: Avoid mixing of two or more insecticides / tank mixing. Repeated application of same insecticide should be avoided. Avoid using insecticides such as pyrethroids which results resurgence of sucking pests. Use neem based formulations. Use selective insecticides (Endosulfan) during early fruiting phase of crop growth.

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Alternate with various chemical groups (Cyclodine, Organophosphates, Carbamates, Pyrethroids and insect growth regulator). • Need based application of recommended insecticides Endosulfan 2ml or Quinalphos 2.5ml or Chlorpyriphos 3ml or Acephate1.5g, Triazophos 2ml or Thiodicarb 1.5g/lt. For eggs control profenophos 2ml or Thiodicarb 1.5g or Triazophos 2ml/lt. In case of more incidence Indoxacarb(Avaunt) 1ml or Spinosad (Tracer) 0.3ml or Emamectin Benzoate(Proclaim 5% SG) 0.5g /lt. • Spray with recommended synthetic pyrethroids in severe cases of bollworm incidence (0.5ml of Decamethtrin 2.8 EC or Cypermethrin 10 EC or Fenvalrate 10 EC or bCyfluthrin 25 SC or 0.25ml/lit Alphamethrin 10 EC, however its use should be avoided or restricted to one or two spays after 100 days of sowing alternating with Insecticides of other groups. Pyrethroids usage should be restricted to twice (1-2) in the cropping period depending on the incidence of spotted and pink bollworms. • Now a days, in case of heavy infestation of the Spodoptera litura, farmers prepare a bait (rice bran+jaggery+insecticide @ 5kg+0.5kg+0.5kg carbaryl or 50ml methomyl) and prepare in small balls, and spray/spread in the field, since the larvae are active during night time (due to this reason, they escape the insecticide spray). • For managing red spider mites application of water soluble sulphur(3g/lt) or dicofol (5ml/lt) must be done. • Similarly if mealy bugs spread in patches to alarming level methyl parathion(3ml/lt) or triazophos (3.0ml/lt) may be used by mixing with sandovit or teepol. Notes:


Lecture 15: (INSECT PESTS OF JUTE, MESTA & SUNHEMP) 15. Insect pests of mesta-distribution-marks of identification-biology, nature and symptoms of damage and management strategies of hairy caterpillar and minor insect pests (aphids, semilooper; flea beetle, mealybug and leafhopper); Insect pest of sunhemp-nature and symptoms of damage and management practices of hairy caterpillar and minor pests (stem weevil, stem borer, flea beetle and mealybug).

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Jute (Corchorus capsularis) is cultivated in Assam, Bihar, west Bengal, Orissa, Tripura and UP. Crop is subjected to the attack of number of insect pests. Mesta (Gogu or Deccan hemp-Hibiscus cannabinus, H. sabdariffa) is grown in many parts of the country. The crop is grown for fiber. Fiber crop is harvested in flowering stage. Many insect pests damage the crop. Sun hemp (Bombay hemp-Janumu-Crotalaria juncea) is an important crop grown for fiber or for green manuring purpose. The fiber is light coloured, coarse, strong and glistening. Grown in almost all part of India. Pod formation is considered the proper stage for harvesting in Uttar Pradesh and MP while in South the fiber crop is harvested in full bloom stage. Number of insect pest attacks this crop.

INSECT PEST OF SUNHEMP (Janumu-Green manure-Rattle box) (Crotalaria juncea) 1. SUNHEMP HAIRY CATERPILLAR / CROTALARIA POD BORER Argina cribraria Arctiidae: Lepidoptera (Tiger moths) Argina astrea Arctiidae: Lepidoptera (Tiger moths) Utetheisa pulchella Arctiidae: Lepidoptera (Tiger moths) • Utetheisa is a genus of arctiid moths. Caterpillars feed on Crotalaria (rattlebox). • The adult moth has white forewings with red and black spots on them and white hind wings with black marginal blotches • Eggs are laid singly or in groups on tender leaves and shoots • The body of the caterpillar is spotted with red, dark and white colors and bear scattered hairs.

Utetheisa pulchella

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The Crotalaria pod borer (Argina astrea) is found in eastern Africa, southern Asia and Indo-Australia, including the Pacific Islands and Australia. The species is extremely variable in wing pattern as well as ground colour. This moth, which is active in the evening, is orange with black spots on all wings, sometimes with some white around the spots. It has a wingspan up to 4 cm across. Eggs are laid in clusters on young leaves. (Egg period: 3-4 days) The larvae feed on Crotalaria species, both leaves and pods. The mature larvae have alternating black and white stripes with some orange associated with the black stripes on the side of the body. (Larval period: 3 weeks) The caterpillars pupate under litter. (papal period: 1 week)

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Argina astrea

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The Caterpillars defoliate the leaves extensively. After flowering, they bore into pods and feed on the seeds.

2. SUNHEMP STEM BORER / SUNHEMP SHOOT BORER Cydia (Laspeyresia) tricentra Meyr, Eucosmidae: Lepidoptera • Adult is small greyish-brown moth. • Caterpillar is pale white with dark brown head and prothoracic shield turning pinkish red when fully developed. • Pupation takes place inside the gall. • Caterpillars bore into the stem near the nodes and feeds on the internal tissues causing the swelling of the region i.e. "gall". • Profuse branching occurs at the affected portion of stem. INSECT PESTS OF MESTA (Gogu or Deccan hemp-Hibiscus cannabinus, H. sabdariffa) 1. MESTA HAIRY CATERPILLAR Euproctis scintillans Lymantriidae; Lepidoptera Euproctis similis

Euproctis scintillans

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2. MESTA STEM WEEVIL Alcidodes affaber Curculionidae: Coleoptera • This insect is a common pest on malvaceous plants in India. • Bhendi, gogu, Bombax malabaricum, Althae rosea and Ficus bengalensis etc. Revised during 2011

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Rose, castor, cotton, pigeon pea, mango, linseed, sun hemp, pumpkin, pomegranate apple and jute etc. The moth is yellowish with a reddish line and spots on the edges. The eggs are laid in masses on the under surface of leaves. Eggs hatch into larvae and feed on foliage. The larva has yellowish brown head and yellow dorsal stripe with a mid-dorsal red stripe. There are tufts of black hairs dorsally on the first three abdominal segments. It pupates in a cocoon of hairs on the leaves or leaf folds. The egg, larval and pupal period respectively being 5-9, 29-35 and 10-12 days. The early instar larvae feed gregariously on the foliage (defoliators).

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Euproctis similis


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The adult feed on leaf buds petiols and tender terminal portion. However serious damage is caused only by the grubs boring into stem and petioles and causing gall like sevellings. Frauss is throughout through holes made on stems. The infested plant gets stunted. Their flowers and fruits production get retarded considerably. A single plant may harbor as many as 12 grubs. This pest is active from September-December.

INSECT PESTS OF JUTE (Corchorus capsularis) 1. JUTE SEMILOOPER Anomis sabulifera Noctuidae: Lepidoptera Anomis involuta

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The adult moth is a medium sized, brownish in colour with dark spots and many lines on forewings. The caterpillar is slender, green with dark green stripes and black spots on the body. In the beginning caterpillar feeds on leaves, as they grow they attack apical buds and top shoots. About 150-200 eggs are laid singly on the lower surface of leaf. Egg hatched in 2-3 days Pupation takes place in the soil in rough cocoons. Some times on leaves, suspended by means of curved hooks of pupa. Dusting 2% Folidol or 10% BHC 10 kg/ac or spraying with methyl parathion 0.05% or DDT 50% WP at 0.2% concentration or BHC 50% WP at the same rate controls the pest.

2. JUTE STEM WEEVIL Apion corchori Curculionidae: Coleoptera • The adult is a small dull black weevil with a long curved snout. Grub is light yellowish in colour with brown head and measures 3 mm in length when full grown. • Grubs feed inside the bark and damage the fiber. As a result of injury knots are formed on the stem and branching takes place. • Eggs are laid singly in the stem near the base of the petiole and on seed pods. Eggs hatch in 3-5 days in to grubs. Larval period lasts for 8-18 days. Pupation takes place in a pupal chamber and lasts for 4 days.

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3. JUTE STEM GIRDLER Nupserha bicolor postbrunnae Cerambycidae: Coleoptera • Adult female girdles stem at two levels as a pre ovipositional operation results the stem withering drooping and finally dying above the level of the lower girdle.


Lectures 15-16 (PESTS OF PULSES) 16. Major insect pests of pulses, beans and peas-distribution-marks of identification-biologynature and symptoms of damage and management strategies of gram caterpillar, plume moth, pod fly, stem fly and spotted pod borer. 17. Minor insect pests of pulses, beans and peas-nature and symptoms of damage and management practices of cowpea aphids, cowbugs, pod bug, leafhopper, stink bug, green pod boring caterpillar and blue butterflies; Insect pests of peas-nature and symptoms of damage and management practices of pea leaf miner and pea stem fly; Insect pests of soybean-nature and symptoms of damage and management practices of stem fly and Spodoptera exigua and minor pest (whiteflies).

Pulses form an important part of Indian dietary. They supply vegetable proteins as essential adjacent to predominantly starchy diets. All these crops are infested by a variety of insects and mite pests. These pests are responsible for both direct and indirect losses.

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1. GRAM CATERPILLAR or GRAM POD BORER (Patcha purugu) Heliothis armigera (Helicoverpa armigera) Noctuidae: Lepidoptera • Redgram in Southern states of India suffers heavy losses due to the lepidopterous borers, especially by Heliothis armigera. • A notorious pest with wide distribution and polyphagous. • Peas, tomato, cotton, maize, tobacco, safflower, groundnut, chillies etc. • The pest is known to feed on a wide array of plants including a range of plants cultivated by humans. • They are the major pest in Red gram, the most polyphagous and cosmopolitan pests. • The pest feeds on a wide range of crops including corn, cotton, alfalfa, bean, grain sorghum, lettuce, peanuts, pecan, pepper, tobacco and tomatoes. • Gram caterpillar also feeds on a wide range of non-cultivated crops depending on geography. • Because of its wide host range, it is known by several common names including corn earworm, cotton bollworm and tomato fruit worm. • This moth is a major pest threat because the larva can feed on a wide range of economically important crops including cotton, corn, tomato, legumes and tobacco. • In addition to feeding on high value crops the old world bollworm is an extremely dangerous pest because: 1) it is extremely fecund, 2) it can sustain itself on over 180 different plant species, 3) it can undergo diapause during adverse conditions and Revised during 2011

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Red gram is mainly cultivated and consumed in developing countries of the world. This crop is widely grown in India. India is the largest producer and consumer of Red gram in the world. Red gram accounted for about 20 percent of the total pulse production of the country during the year 2000-2001. Red gram is an annual crop. Based on its maturity, it is classified as: Extra early : 120 days duration, Early : 120150 days duration, Mid 150-180 days and, Late maturing in more than 180 days, S1 and S2 are the late duration varieties. Based on growth habit, red gram is divided into 1. Determinate type (clustering) and 2. Indeterminate (branching types). Based on this different pests are affecting. Damage to pods of early and mid-maturing cultivars of determinate habit caused by lepidopterous borers is very severe. Pod fly is much more important in late maturing cultivation.

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4) it can migrate over long distances. To make matters worse, the bollworm has evolved a high degree of resistance to organophosphate and pyrethroid insecticides. Marks of identification: Adult: The adult moth is described as a typical Noctuid. The stout bodied / heavy bodied moth has a wing span range of 35-40 mm and the body length range of 18-19 mm. Forewings dark yellow grey or brown with a dark cross band near outer margin and dark spots near costal margins (center of forewings), and are relatively smaller than hind wings. The coloration varies from dull greenish yellow to olive gray or light brown and females are darker than males. Eggs: The eggs are spheres approximately 5 mm in size, which are initially white in coloration, then darken to grayish brown prior to eclosion. The eggs are sculptured with vertical ridges of alternating length, which surround a smooth apical area that contains the micropyle. Eggs are laid singly on the reproductive structures of plants. Larvae: First instar larvae are cream to white with a dark head, with a spotted appearance due to sclerotized setae, tubercle bases and spiracles on body. Larva relatively smooth (hairless). Larval color darkens with successive molts for the 6 instar stages (typical), and coloration can vary considerably (yellow, brown, red or cream) due to diet content. The caterpillars are greenish with darker broken lines along the side of the body. Head capsule of older larvae dark yellow or orange. •

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Symptoms of damage: • Newly hatched larva eats the egg sheath and then wanders in search of a good site to feed. • Young larva feed on leaves, flowers, and pods. • The young caterpillars feed on the tender foliage. Small larvae feeding on leaf tissue may result in pinhole damage. • As the caterpillars grow, they bore into the pods and destroy the seeds, while feeding it thrusts its head inside the pod leaving the rest of its body outside. • Older larvae can destroy pods. On the pods, the larva can be seen feeding by inserting head and half of the body inside the pod. • Feeding on pods results in round holes on pods. They eat away completely the seed. • Typically, larvae move down the plant as they mature. • Preferred feeding sites include flowers, buds, pods and leaves.

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Life cycle: • Adult female lays sphere shape eggs, singly, on the reproductive structures of plants and incubate for approximately 3-14 days depending on temperature. • First instar larvae are cream to white with a dark head, with a spotted appearance due to sclerotized setae, tubercle bases and spiracles on body. Larva relatively smooth (hairless). Larval color darkens with successive molts for the 6 instar stages (typical), and coloration can vary considerably (yellow, brown, red or cream) due to diet content. Typically there are 5-7 instars and a larva period of 12-32 days before pupation occurs. • Pupation occurs in the ground (earthen cell). The pre-pupal stage will last for 1-4 days. The pupal period will take 10-14 days if the bollworm is not in diapause. If in diapause, the pupal period can take several months to complete. Seasonal incidence & factors of abundance: • Minimum temperature and evening relative humidity exhibited highly significant negative correlation with the gram pod borer population. The larval populations started increasing and reached its maximum of 12.97 mean larval population/plant during 4th week of March (12th standard week). The population has significantly positive correlation with both minimum and maximum temperature and the correlation coefficient being 0.71 and 0.82, respectively. Management: • Deep ploughing. • Crop rotation with other non-host plants (breaks life cycle, increases natural enemies population). • Intercropping groundnut • Trap crops (marigold) for monitoring egg laying, and also killing the neonates. • Use pheromone (helilure) traps @ 4/acre for pest monitoring, forecasting & trapping males. • Light traps @ 1trap/5acres, to monitor the pest population, and also killing. • Arrange bird perches @ 10/acre. • Release Trichogramma egg parasitoids @ 20,000/acre at an interval of 3-4 weeks. • Release of Chrysoperla predators @ 4000/acre. • Topping of cotton plants during early stage when maximum egg laying is noticed, to remove eggs. • Spray HelioNPV @ 500LE/ha or Bt formulations @ 2gm/L, 5% NSKE in synchrony with early larval instars. • Mechanical collection and destruction of larva is highly recommended, when larva grows big. • Shaking of the plants also helps in mechanical collection of grownup larva. • Do not use the same pesticide, repeatedly. • First spray to be given at 50% flowering spray, subsequent sprays at fortnight intervals, if required. • Spray endosulfan / quinalphos / chlorpyriphos / triazophos / acephate / fenvalerate / cypermethrin, if overlapping populations present. • Spray pesticides like endosulfan and chlorpyriphos with sesamum oil (synergist). • Two precautions are necessary to ensure success 1) the insecticidal application should be so timed as to coincide with the peak of the hatching of eggs, so that the just hatched larvae may get the fatal dose before entering the plant tissue. 2) The parasite activity in the field should be carefully assessed before the insecticidal application.

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2. REDGRAM PLUME MOTH Exelastis atomosa (Walsingham) Pterophoridae: Lepidoptera • Specific pest of red gram in India, AP. Assam, Bihar, Maharashtra and Tamilnadu. Marks of identification: • The moths are slender, less than 12 mm long and are grey with long narrow wings. • The forewings are divided into two parts and hind wings are cut into three parts and provided with a fringe like borer. • The full grown caterpillar about 12 mm long greenish brown in colour and are fringed with short hairs and spines.

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3. REDGRAM POD FLY Malanagromyza obtusa (Malloch) Agromyzidae : Diptera • Key pest of pigeonpea throughout south and south-east Asia. • Attack is more in North and Central India and Karnataka. • In North India, it causes 80% loss in seed yield. • Other hosts are safflower and bhendi. On these maggots mine into the stem and causes wilting. Marks of identification: • Adult is a black fly with strong legs and ovate abdomen. Its eye are distinct, wings are clear veined, brownish yellow at their bases.

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Nature & Symptoms of damage: • Caterpillar first scrapes the surface of pods, enters into the pod by cutting a small hole and feeds on seeds. • Attacked seed is completely eaten away by the caterpillars, unlike pod fly. • The larva also feeds on unopened flower buds consuming the anthers and causing flower drop. • This pest is usually found at flowering and known to cause heavy damage to redgram. • Attack by this pest can cause severe bud, flower and pod drop. Life cycle: • Minute eggs are laid singly on round pods, flower buds and young leaves. • The full grown caterpillar about 12 mm long greenish brown in colour and are fringed with short hairs and spines. • Pupation takes place outside the pod, pupa looks similar to larva. Pupation on pod surface or burrows of infested pods pupa is also fringed with short hairs. Pupal period 4-8 days. Management: • Collection of caterpillars by shaking shoots and their destruction in initial stages. • Timing is important is taking plant protection measures. • Note: After 50% flowering is observed commence sprayings. Same as gram caterpillar control measure. • Parasites of Apanteles sp feed on larvae.


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Females insert eggs into the shell of green tender pods of pigeonpea and other host plants. Maggot is creamy white in colour.

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4. BEAN STEM FLY / BEAN STEM MAGGOT / BEAN FLY / PEA STEM FLY Ophiomyia phaseoli (Tryon) Agromyzidae Diptera • A minor pest on cowpea is known to attack all beans and many other legumes. • It has been noticed on Phaseolus-beans, cowpea and lablab beans. • The bean fly is a very small inconspicuous fly. • The tiny white eggs are laid individually in small holes in the leaf surface. • The egg hatches on the leaf and the small white maggot bores down through the stem and feeds just above ground level. Here the stem will swell and crack.

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Nature & symptoms of damage: • The young larvae find themselves directly on the soft seed on which they feed. • Initially larva bores into epidermis without rupturing the seed coat. • In the second and third instar stages, the larva bores into cotyledons and in most instances one seed is sufficient for the maggot to complete its development. • The final instar larva leaves the seed and prior to pupation, windows the pods and pupates either in the pod cavity or in the pod wall tissue. • The damaged seeds are unfit for consumption. • In affected pods, no visual symptoms are observed regarding its entrance. After opening only the pest attack is identified. • Substantial yield losses have been attributed to this pest in several countries. • Difficult to detect the pod fly incidence externally at the green pod stage. Discoloration of the infected parts is visible in green podded varieties. At the later stage of infestation, the holes are about 1mm in diameter covered with a thin membrane can be readily seen on the infested pod. Exit holes are visible after the adult emergence. Life cycle: • Small blackfly thrusts to minute eggs into the tissue of the tender pod and flower buds. Fly pierces pericarp with ovipositor and lay egg and are seen like needles projecting inwards from the pods. Egg period 3 days. Lays 4 eggs per pod and 80 eggs in its life time by female fly. • Maggots enter the seeds and feed on inner contents of seeds. Sometimes cover is intact. Larval period 6-10 days. • Full grown maggot pupate inside larvae grooves in pods. Pupal period 8-12 days. • Adults emerge by cutting the thin spot already made by maggot. Management: • Removal of affected pods of first brood during winter. • Advancing of sowing dates in endemic areas. • Chemical control same as that of gram caterpillar.


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5. SPOTTED POD BORER / BEAN POD BORER / SOYBEAN POD BORER / MUNG MOTH / MARUCA POD BORER (Maruka Matchala Purugu) Maruca vitrata (testulalis) (Geyer) Pyralidae: Lepidoptera • The soybean pod borer is a devastating insect pest of many legume crops in tropical and semitropical regions, such as Africa, southeastern Asia, Australia, Mexico and parts of South America. • This pest is found throughout South India. • Maruca vitrata is a Pantropical insect pest of leguminous crops like pigeon pea, cowpea, mung bean and soybean. • Soybean, Cowpea is also a common host of this pest. • Adults are small, less than an inch wide at the wing tips. Adult moth with light brown forewings having white markings and white hind wings with brown markings at the lateral edge. • They are nocturnal and seldom seen in the field. Revised during 2011

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Bean flies cause a characteristic swelling of the stem at ground level where the maggots (fly larvae) burrow into the stem. The maggots pupate at the base of the plant and as the stem grows it often cracks open. Pupae can be found in the cracks and on the outside of the stem. Leaf symptoms are more difficult to spot in field crops. One or two leaves on the plant turn yellow while the other leaves remain green. The petiole often shows dark streaks where the maggots have moved through and damaged tissue. Damage on Phaseolus-bean is severe and often results in complete crop loss. The young plants wilt and die without setting pods. Attacks were also recorded on cowpea and lablab bean. Leaf symptoms are not easy to see, but the swelling of stems at ground level is always visible. The affected plants wilt and gradually dry up leaving many gaps in the field.

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Larvae are pale-colored and feed on the floral parts and pods of legume plants, rendering them unmarketable. Eggs are laid on the sepals or petals of the flower. The larva feeds for about 3 weeks. At night, it emerges from the pods and crawls about; it then descends to the soil and pupates beneath leaf debris. The caterpillar webs together the flowers and feeds on them. It also bores into pods at one end and eats up the ripening seeds. At the entrance, mass excreta can be seen at larval furrow. Because of the hidden nature of larval stage (the damaging stage) and pupal stage, it is difficult to control Maruca pod borer by chemicals or other conventional means. Pupation within the debris near the ground.

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Spraying to be initiated at 50% flowering. Refer: Pob borer for management.

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6. BLACK BEAN APHIDS / BLACK FLY (Penu Banka) Aphis fabae Aphididae:Homoptera Aphis craccivora Aphididae:Homoptera • A polyphagous pest infesting Redgram and other pulses, citrus etc are other host plants. • Both nymphs and adults suck sap from tender leaves and shoots resulting into attack of saprophytic fungus, ultimately leading to devitalization of plants. • It acts as a vector of Rosette of groundnut virus disease.

7. COW BUG Oxyrhachis tarandus Membracidae : Hemiptera • This species is common all over south India. • It is one of the major pests of redgram. Revised during 2011

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Spray tobacco decoction (1 kg tobacco boiled in 10 lit of water of ½ hour and make up to 30 lit + 100 g soap). Systemic insecticides like monocrotophos 0.04% or dimethoate 0.03% or phosphamidon 0.05% or malathion 0.1% spraying controls the pest effectively.

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7 mm long gray-brown bugs have thorn-like projections on the thorax. Eggs are laid on the stem. The nymphs exude honey dew liquid which is used by ants. The bugs suck the green stems. Formation of corky calluses. Wilting, and reduced plant vigor.

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Dust 10% BHC at 8 kg / acre in early stage. In later stages dust 10% DDT at 10 kg per acre.

8. PULSE POD BUGS / POD SUCKING BUGS : Coreidae:Hemiptera Clavigralla gibbosa Riptortus linearis Anoplocnemis phasiana

The adult is wedge shaped short bug and dusky brown in color. Eggs are laid in groups and are pinkish to orange in color.

Both nymphs and adults bugs suck the sap from developing pods and seeds. Hundreds of bugs nymphs and adults suck sap from the shoots and pods. Shoots fade; pods shrivel due to the feeding of bugs. Pods with black spots; shedding of green pods, poorly filled pods with shriveled grains inside. Collection of bugs and their destruction by dipping into kerosinated water. Dusting or spraying with DDT or BHC 10% dust.

9. GREEN POD BUG / GREEN STINK BUG Nezara viridula Pentatomidae: Hemiptera • Commonly known as the Green Stink Bug or Green Vegetable Bug, is a plant-feeding stink bug. • Nezara viridula is a cosmopolitan species, living in tropical and subtropical regions of Americas, Africa, Asia, Australasia and Europe between 45 degrees north and 45 degrees south. • Its exact origin is unknown, but it is believed to have originated from the Ethiopia region of East Africa, from where it has spread around the world due to its strong flight and human trade routes. • Food plants comprise a very wide range of fruits and ornamental trees, field crops, vegetables, and weeds. Hosts crops of economic importance include beans, cabbage, Revised during 2011

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A large dark brown bug with enlarged and curved hind legs

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Adults are brown wedge shaped, flat, and narrow bodied bugs with enlarged hind femur. Eggs are laid singly on the pods at their base.


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chinese cabbage, citrus, crucifers, curcurbits, green beans, head cabbage, macadamia nuts, mango, mustard cabbage, orchids, peppers, potatoes, soybeans, tomatoes, watercress and yardlong beans. Important weed hosts include spiny amaranth, castor bean, popolo berry, rattlepod, spiderweed, and cheese weed. Its omnivorous feeding habits make it an important pest throughout its distribution range. Because of its preference for certain species of legumes, such as beans and soybeans, it is an economically important pest on such crops. Adults are approximately a centimeter long, bright green and shield-shaped. Nezara viridula reproduces throughout the year in tropics, and except for the winter time, in temperate zones as well. The female lays 30 to 130 eggs at a time, in the form of an egg mass glued firmly to the bottom of a leaf. The eggs are barrel-shaped, with an opening on the top. The newborn larvae (nymph) gather near the empty eggs and do not feed until three days later, after the first moult. They moult five times before reaching maturity, increasing in size each time. Each instar stage lasts about a week, except for the last one before the metamorphosis, which is a day longer. Up until their third moult the larvae aggregate together on the host plant, the purpose of this aggregation is probably pooling of chemical defenses against predators, for example ants. The bugs feed by piercing plant tissue with needle-like stylets. The actual feeding puncture is not immediately visible. Adults and nearly all nymphal stages (2nd to 5th nymphal stages) feed on a variety of plant tissue. Succulent parts of the plant and the developing flowers or fruit are preferred. Feeding injury becomes visible sometime after actual feeding. Feeding on flower buds results in premature abscission. Feeding injury on leguminous pods results in seed damage and ultimately distorted development of the pods.

Mechanical collection & destruction of nymphs and adults. Spray with carbaryl 0.15% or endosulfan 0.07%.

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10. BROWN STINK BUG Euschistus servus Pentatomidae: Hemiptera Halyomorpha halys Pentatomidae: Hemiptera • Commonly known as the Green Stink Bug or Green Vegetable Bug, is a plant-feeding stink bug.


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The bug is indigenous to Asia and is considered an agricultural pest in Japan. The insects have been found in trees and in houses, where they produce a pungent, malodorous chemical. This Stink Bug is brown with a checked border beneath its wing covers, is 1/2 inch long, and shaped similar to a shield. It lays its eggs on leaves and fruit. The insect can be an agricultural pest, threatening apples, pears, peaches, figs, mulberries, citrus, persimmon and soybeans. This pest damages blackberry, cabbage, corn, grams, peas, peach and tomato plants, when the adults and nymphs puncture the fruit skins, causing a gummy substance to appear. It is an agricultural pest that can cause widespread damage to fruit and vegetable crops. In Japan it is a pest to soybean and fruit crops. In the US, the brown marmorated stink bug feeds, beginning in late May or early June, on a wide range of fruits, vegetables, and other host plants including peaches, apples, green beans, soybeans, cherry, raspberries, and pears. It is a sucking insect, a "true bug” that uses its proboscis to pierce the host plant in order to feed. This feeding results, in part, in the formation of small, necrotic areas on the outer surface of fruits but ranges from leaf stippling, cat-facing on tree fruits, seed loss, and transmission of plant pathogens. The injured fruit will appear pitted. Many similar stink bugs are predaceous. This insect produces one generation each year and can hibernates as an adult or egg. The most effective preventive maintenance is weed control. The pests are also vulnerable to soap sprays.

11. REDGRAM GREEN POD BORER or LENTIL POD BORER Etiella zinckenella (Treitschke) Pyralidae: Lepidoptera • It is found in South Indian plains, occasionally it becomes serious. • Redgram, horsegram & other pulses and green manure crop like sunhemp are host plants. Marks of idenfication: • Brownish grey moth with white stripe along the anterior margin of each forewing and orange prothorax. • Eggs are laid singly or in groups at the junction of the calyx and pod or on the pod surface. • Newly hatched larvae feed on floral parts and later bore into the pods and feed on seeds, lead to Dropping of flowers and young pods. The caterpillars are greenish initially having 5 black spots on the prothorax, turn pinkish before pupation • Pupation takes place in the soil. • Management practices: refer gram pod borer

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It is also known as the Cluster caterpillar, Cotton leafworm, Tobacco cutworm, and Tropical armyworm. It is found throughout the tropical and sub-tropical parts of the world. Revised during 2011

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12. TOBACCO CATERPILLAR (Pogaku ladde purugu) Spodoptera litura (Fabricius) Noctuidae: Lepidoptera


They are International Pests. Wide spread in India. Besides tobacco, feeds on cotton, castor, groundnut tomato, cabbage and various other cruciferous crops. Marks of identification: • Moths are medium sized and stout bodied with forewings pale grey to dark brown in colour having wavy white markings and whitish hind wings. • The female lays eggs in masses and covers them with hair scales from her body (anal tuft hairs). • Larvae are variable in colour starting pale green and turning dark green to brown. Caterpillar is velvety black with yellowish green dorsal stripes and lateral white bands. A dark rings like structure is seen on anterior and posterior region in early stages.

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Nature & symptoms of damage: • They are chiefly defoliators. • The early instars are gregarious and scrape the chlorophyll content of leaf lamina giving it a papery white appearance. Larvae feed gregariously for first few days and then disperse to feed individually. • Later irregular holes are made on the leaves. • During later instars, they skeletonize the leaves leaving only veins and petioles. • During flowering and boll formation stage, the caterpillars also feed on the internal contents of bolls and cause irregular holes. Life cycle: • Pest breeds throughout the year. • Moths are active at night. • Female lays about 300 eggs in clusters. • The eggs are covered over by brown hairs and they hatch in about 3-5 days. • Larvae feed gregariously for first few days and then disperse to feed individually. • Pass through 6 instars. • Larval stage 15-30 days. • Pupation inside the soil, pupal stage 7-15 days. • Adults live for 7-10 days. • Total life cycle 32-60 days. • 8 generations in a year. Management: • Management practices are same as other bollworms. • Trap crop: castor • Use/spray SLNPV @ 500LE/ha. • The larvae develops very thick skin once in third instar, and it becomes very difficult to manage the pest even with high dose of insecticides, and hence, it is always better to follow practices like collection & destruction of egg masses and neonate larval groups, erection of bird perches etc.

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Now a days, in case of heavy infestation of the pest, farmers prepare a bait (rice bran+jaggery+insecticide @ 5kg+0.5kg+0.5kg carbaryl or 50ml methomyl) and prepare in small balls, and spray/spread in the field, since the larvae are active during night time (due to this reason, they escape the insecticide spray). Use pheromone traps with Litlure.

13. BLUE BUTTERFLY Lampides boeticus (Linnaeus) Lycaenidae; Lepidoptera • Redgram, cowpea, lab lab, niger etc. are the host plants. • Adult blue butterfly with ventral side of wings with numerous stripes.

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Eggs are laid singly or in groups on flower buds, green pods, shoots and leaves. Pale green colored larva, flat and slightly rounded, hairy and slug like. After hatching the tiny caterpillars enter into unopened flower bud and feed inside. After wards they may attack another flower or enter a pod and feed on the developing seeds. The larva feeds on flowers, flower stalks and pods. Buds, flowers and young pods are with bored holes. Pupation takes place on leaves, twigs and pods.

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14. Spodoptera exigua (Refer paddy)


Lecture 18: (INSECT PESTS OF CASTOR) 18. Major insect pests, of castor-distribution-marks of identification biology-nature and symptoms of damage and management strategies of semilooper, shoot and capsule borer, tobacco caterpillar. Minor insect pests of castor-nature and symptoms of damage and management practices of leafhoppers, butterfly, whitefly, thrips and castor slug. 19. Major insect pests of groundnut-distribution-marks of identification biology-nature and symptoms of damage and management strategies of white grub, leaf miner, RHC and tobacco caterpillar; Minor insect pests of groundnut-nature and symptoms of damage and management practices of Helicoverpa, leafhoppers, thrips, aphids, pod bugs and jewel beetle. 20. Major insect pests of sesamum-distribution, marks of identification, biology-Nature and symptoms of damage and management strategies of leaf arid pod borer and gall fly; Minor insect pests of sesamum - nature and symptoms of damage and management practices of sphinx caterpillar; Major insect pests of safflower-nature and symptoms of damage and management practices of aphid; Minor pests of safflower-nature and symptoms of damage and management practices of Helicoverpa and Spodoptera exigua. 21. Major insect pests of mustard-distribution-marks of identification biology-nature and symptoms of damage and management strategies of aphids, sawfly and diamondback moth; Minor insect pests of mustard nature and symptoms of damage and management practices of painted bug; Major insect pests of sunflower-distribution-marks of identification-biologynature and symptoms of damage and management strategies of Helicoverpa and Spodoptera; Minor insect pests of sunflower-nature and symptoms of damage and management practices of leafhoppers, bihar hairy caterpillar and thrips.

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Oilseed crops viz., castor, groundnut, safflower, sunflower, mustard, til are infested by a variety of insect and mite pests. Some insects’ viz., jassids cause very serious damage in the seedling stage of castor, while defoliators and borers are major pests of grown up crops. These pests have to be controlled, so that they may not cause economic losses.

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1. CASTOR SEMILOOPER (Naamala purugu / Daasari purugu) Achaea janata (Linnaeus) Noctuidae: Lepidoptera Paralellia algira Linnaeus Noctuidae: Lepidoptera • Achaea janata is found in many parts of the world including Asia, the south Pacific, and most of Australia. • This is a serious pest of the oilseed crop and is distributed throughout the Indian Union, wherever castor is grown. It is occurring during July to September. • Castor Semi-Looper caterpillars feed on many plants including pomegranate, rose, White Mangrove, Orchid Trees (Bauhinia species), Soybeans, Cotton, Wattles, Eucalyptus species, Macadamia Nuts, Lychee, and many weed species. It is a pest of Pine seedlings, Tamarind, Castor Oil Plants. Marks of identification: • Achaea janata is a dark brown coloured moth, with light and dark brown patterned forewings, and black and white hindwings • Paralellia algira is also stoutly built moth. In forewings and hind wings, there are two whitish lines which are parallel and continuous white markings are not present in forewings of moth. • Larva is a semilooper, long smooth grayish brown in colour. The first pair of prolegs are reduced and hence are called semilooper. • The fully grown larvae are smooth greyish brown in color with pale white stripes, and hence it is commonly known as Namalapurugu or Dasari purugu.

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INSECT PESTS OF CASTOR


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Full grown larva has black head a red spot on the black loop and red anal tubercles and measures 60-70 mm in length.

Nature & symptoms of damage: • The smooth greyish-brown caterpillars feed on the leaves. • The caterpillar feeds sparingly at first and during later stages feeds voraciously. • Heavy defoliator, only mid rib and veins are left on the plant.

Life cycle:

Female moth lays about 450 blue green rounded and ridged eggs singly on tender leaves and floral parts. Egg period 3-4 days. • The newly hatched caterpillar is yellowish green in color with light brown head and thorax. 2nd and 3rd instar caterpillars are very destructive. Larval period 15-20 days. • Pupation takes place in the soil or among fallen leaves (leaf folds). Pupal period 10-14 days (during warm weather) a few months (during cold weather). Management: • Delay planting up to mid-august in endemic areas. • Observe second leaf and second shoot from top for the eggs and egg masses. • Handpicking & destroying the larva is the best practice.

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Braconid larval parasitoid: Microplitis ophiusae, M. maculipennis acts as larval parasite whose cocoons may be seen attacked to the central aspect of the posterior end of the host caterpillar, which keeps the pest under check in certain times. Spray endosulfan (2ml/L), quinalphos (2ml/L), chlorpyriphos (2ml/L), acephate (3gm/L), methyl parathion (1.5 ml/L) or other OP compounds if 4-5 semiloopers are observed/plant on 30-40 days old seedlings. Spray 4% NSKE coinciding with egg laying, and early larval stages. Arrange bird perches @10/acre.

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Nature & symptoms of damage: • Infestation starts from flowering stage, usually active during November-february. • Larvae bore into the shots as well as capsules and destroy them. • Occasionally the larva is found at the junction of the petiole with the lamina and rarely in thick mid rib. • External indication is the existence of frassy matter at the bored shots and webbed conditions of seed capsules covered with dark excreta. Life cycle: • Female moth lays pinkish oval, flat eggs singly or in groups on tender parts of plant (tender developing capsules). They hatch in 6-7 days. • Caterpillar is reddish-brownish in colour, and fine hairs arising from warts on the body. The head and prothorax are brown. • The larva bores into terminal shoots and seed capsules. Full grown caterpillar is 1525mm long. Larval period 12-16 days.

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2. CASTOR SHOOT AND CAPSULE BORER / CASTOR POD BORER / YELLOW PEACH MOTH Dichocrocis punctiferalis Pyralidae : Lepidoptera • It is potential pest and occasionally becomes serious. • Ginger, turmeric, cardamom, guava, Jack, mango, cacaos, peach, soap nut tree etc. are host plants. • It is active from September to February when crop is in flowering. • The pest is distributed throughout the plains and hills of India. Marks of identification: • The moth is medium sized having bright orange yellow coloured wings and with numerous black dots or spots. The body length is about 10 mm while the wingspan is 22 mm. • Caterpillar is brownish with pinkish tinge and fine hairs arising from warts on the body. The head and prothorax are brown.


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Pupates inside the damaged stem or capsule in a thin silken cocoon. Pupal period 7-10 days. Total life history from 25-33 days. Three generations per year.

Management: • Collect & destroy infested shoots & capsules. • Spraying should be started from flowering stage and 20 days after. • Direct the spray on primary & secondary sprays in order to check further spread to higher order racemes. • Sprays-follow recommendation for semilooper. 3. TOBACCO CATERPILLAR Spodoptera litura (Fabricius) Noctuidae:Lepidoptera Besides castor, feeds on groundnut, soybean, cotton, tobacco, castor, groundnut, tomato, cabbage, and various other cruciferous crops. • It is also known as the Cluster caterpillar, Cotton leafworm, Tobacco cutworm, and Tropical armyworm. • It is found throughout the tropical and sub-tropical parts of the world. • They are International Pests. • Wide spread in India. Marks of identification: • Moths are medium sized and stout bodied with forewings pale grey to dark brown in colour having wavy white markings and whitish hind wings. • The female lays eggs in masses and covers them with hair scales from her body (anal tuft hairs). • Larvae are variable in colour starting pale green and turning dark green to brown. Caterpillar is velvety black with yellowish green dorsal stripes and lateral white bands. A dark rings like structure is seen on anterior and posterior region in early stages.

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Nature & symptoms of damage: • Castor is the most preferred host for egg laying and feeding. • They are chiefly defoliators. • The early instars are gregarious and scrape the chlorophyll content of leaf lamina giving it a papery white appearance. Larvae feed gregariously for first few days and then disperse to feed individually. • Later irregular holes are made on the leaves. • During later instars, they skeletonize the leaves leaving only veins and petioles. • During flowering and pod/capsule formation stage, the caterpillars also feed on the internal contents of capsules and cause irregular holes.

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Life cycle: • Pest breeds throughout the year. • Moths are active at night. • Female lays about 300 eggs in clusters. • The eggs are covered over by brown hairs and they hatch in about 3-5 days. • Larvae feed gregariously for first few days and then disperse to feed individually. • Pass through 6 instars. • Larval stage 15-30 days. • Pupation inside the soil, pupal stage 7-15 days. • Adults live for 7-10 days. • Total life cycle 32-60 days. • 8 generations in a year. Management: • Management practices are same as other bollworms in cotton (refer to cotton). • Use/spray SLNPV @ 500LE/ha. • The larvae develops very thick skin once in third instar, and it becomes very difficult to manage the pest even with high dose of insecticides, and hence, it is always better to follow practices like collection & destruction of egg masses and neonate larval groups, erection of bird perches etc. • 4% NSKE at early gregarious stages. • Now a days, in case of heavy infestation of the pest, farmers prepare a bait (rice bran+jaggery+insecticide @ 10kg+1kg+1kg carbaryl or 100ml methomyl or 1L of monoctopohos in 1L water and prepare in small balls, and spray/spread in the field, since the larvae are active during night time (due to this reason, they escape the insecticide spray). Broadcast the bait on rows during evening, as the pest is noctiurnal. • Use pheromone traps with Litlure.


4. CASTOR SLUG CATERPILLAR Parasa lepida Limacodidae: Lepidoptera • The Nettle Caterpillar or Blue-striped Nettle Grub (Parasa lepida), is found in the Indo-Malayan region, including India, Sri Lanka, Vietnam, Malaysia and Indonesia. • Most common in southern regions, especially in Madras and has been recorded in Ceylone also. • It is an introduced pest to urban trees in western Japan. • The larvae are considered pests and have been recorded from coffee, coconut, oil palm, cocoa, tea, citurs, woodapple and mango. • A sporadic pest of castor larvae feed on the leaves having only the mid rib and veins. Marks of identification: • Adult is a green moth with brown band at the base of each forewing. • Larva is slug like, ventrally flat, greenish body with white lines and four rows of spiny scoli tipped red or black. When touched, cause irritation.

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5. CASTOR LEAFHOPPERS / JASSIDS Sundapteryx biguttula biguttla (Empoasca flavescens) Cicadellidae: Homoptera • Minor pest, recorded in Bihar, Assam, AP, TN and Assam, also infesting Tea. • Peak infestation during November-January, usually seen on tender seedling stage. • Adult greenish yellow, wedge shaped with pair of black spots on vertex and on each of forewings. • Female inserts eggs on underside of leaf veins. Egg period 7-10 days. • Nymphs are pale greenish almost translucent walk diagonally. Nymphal period 7-9 days. • Nymphs and adults suck the sap from underside of leaves, causing burnt appearance, downward curling. • Inject toxins causing leaf curls on edges and leaves turn red and brown. • Leaves dry up and drop.

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Nature & symptoms of damage: • They feed gregariously in the beginning, and spread to other leaves. • They feed oraciously and are the chief defoliators. Life cycle: • Female moth lays flat scaly eggs on tender parts of plants in small clusters. • Fully grown caterpillar grows to 1.5-2.5 cm. • Bright green color larva with rows of spines, moves like slug. • Pupation in hard greyish cocoon on castor stem. • Pupal period for 3-4 weeks. Management: • Gregarious larvae to hand picked & killed. • Large number of coccons found at tree trunks of castor stems can killed spraying water mixed with kerosene. • If the pest attck is more, spray insecticides like endosulfan, chlorpyriphos or methyl parathion.


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Completes 7-8 generations per year. EIL: 2-3 /plant. Seed treatment with systemic insecticides. Spray systemic insecticides.

6. RED HAIRY CATERPILLAR Refer to Groundnut 7. BIHAR HAIRY CATERPILLAR Spilosoma obliqua Arctiidae: Lepidoptera (Tiger Moth) • This pest occurs during October-December, and of late it is also occurring from July. • In recent years it has become an important pest of Groundnut also. • Adult moth is reddish brown with black spots. • Both wings are pinkish with black spots. • Females lays eggs on leaves in masses. • The larvae are pale yellow coloured, with yellow hair over the body. • They are polyphagous, feed on leaves, and cause loss by defoliation. • In severe cases, only stems are left. • In defoliated crops, also feeds on capsules. • Pupate in leaf litter close to the plants. • Several generations per year.

8. CASTOR THRIPS Scirtothrips dorsalis Hood Thripidae; Thysanoptera Retithrips syriacus • Very tiny pinkish nymphs and black adults with fringed wings feed both on the upper and lower surfaces of leaves. • The terminal leaves crinkle and appear silvery. • Severe infestation results in stunted growth. • In severe infestation, spray systemic insecticides. Revised during 2011

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Collection & destruction of eggs and early stages. Spray 4%NSKE. Spray endosulfan, chlorpyriphos, monocrotophos etc.

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9. CASTOR WHITEFLY Trialeurodes rara Trialeurodes ricini Aleurodidae : Homoptera • It is more commonly found in Bihar, AP, Maharastra and TN. • More serious in summer months. • Temp > 300C with high RH favors the pest. • Adult fly is yellow with white wings, pale white legs and antenna. • Female lays tiny eggs in small clusters underside of the leaf. • The yellowish nymphs with waxy filaments are found in large numbers on leaves. • Nymphs and adults suck sap causing yellowing and drying of leaves when severe infestation occurs. • Predacious spiders, coccinellids feed. • Stem application of monocrotophos (refer cotton) • Spray any systemic insecticides.

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10. SERPENTINE LEAFMINER (American serpentine leafminer, serpentine leafminer, broad bean leafminer, Californian leafminer, celery leafminer, chrysanthemum leaf miner) Liriomyza trifolii Agromyzidae:Diptera • Liriomyza trifolii is highly polyphagous. • Distributed throughout world. • An invasive pest was accidentally introduced into India from American sub-continent along with chrysanthemum cuttings. • In India, it was initially recorded on 55 plant species and later on about 79 species that included pulses, oil seeds, vegetables, green manures, and fodder and fibre crops. • The larval leaf mine vary in form depending on the host but when adequate space is available the mine is long, narrow and not greatly widening towards the end. • Larval mines in small leaves with limited feeding space are characterized by a secondary blotch. • Damage caused by a single larva is minimal, however when large populations are present they are capable of destroying leaves and affecting the growth of plants. • The average period of the life cycle of the celery leafminer is 21 days, but can be as short as 15 days. The length of the life cycle varies with host and temperature. • Eggs are laid singly in punctures in the leaf epidermis. There is no preference for upper or lower surface. The freshly laid eggs are creamy white and shaped like an elongated oval. The eggs are small, and hatch 2-4 days. • The maggots are bright yellow to yellow green in color. There are three larval stages. Each larval instar is completed in 2 - 3 days. • The first larval stage burrows into the mesophyl tissue. The second stage also feeds in the mesophyl tissue. The third stage larva concentrates its feeding towards the upper leaf surface. When it is mature, it cuts a longitudinal slit in the leaf and leaves to pupate on the leaf surface or on the ground.


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The pupal stage is yellow-brown in color and distinctly segmented and development is completed in 5 to 12 days. This adult is a small fly of mat gray with black and yellow splotches. Adults live for 10-20 days depending on environmental conditions. Spray 4% NSKE or any systemic insecticide.

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11. HAIRY CATERPILLAR (Yellow tail / Goldtail Moth) Euproctis similis Lymantriidae: Lepidoptera • Polyphagous, cosmopolitan pest. • Occasional pest in castor. • Larvae with gregarious habit, and eats all parts of the crop. • The pest was recorded in large numbers in castor crop at Jagtial during 2010 and 2011, and students have collected large number of larvae and adults during 2010-11.


INSECT PESTS OF GROUNDNUT

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The damages caused by insect pests of groundnut crop both in field as well in storage are enormous. An annual loss due to insect pests problem is estimated to be around Rs. 1500 million. In India, about 115 insect pest species cause damage, of which only 9 species (leafminer, white grub, jassid, thrips, aphid, tobacco caterpillar, gram caterpillar, red hairy caterpillar and termites) are found to be economically important. Leafminer is considered to be one of the national pests of groundnut in India. This insect pest has become a serious problem in Southern states, Maharashtra, Bhubaneshwar area of Orissa and Gujarat in both kharif and rabi/summer seasons. White grub is another pest of national importance and causes serious yield loss in the sandy loam soils of North India. This pest has also been reported to be occurring in Maharashtra (Digraj, Parbhani), Madhya Pradesh, localized areas in Andhra Pradesh, in north and north east Gujarat, and in areas surrounded by mountains of Dhencanal district of Orissa. Due to the menace of white grub, the groundnut area in the states of Uttar Pradesh, Rajasthan, Punjab and Haryana has shown declining trend. Major jassid problem is in Gujarat, Maharashtra and Tamil Nadu. Thrips are important pests of groundnut in Karnataka, Orissa, some parts of Maharashtra, Andhra Pradesh and Gujarat. Frankliniella schultzei is a vector of bud necrosis virus disease, Aphids are sporadic pests of groundnut in India although they are common in Maharashtra and Orissa states. Tobacco caterpillar has become an important pest only recently. At present it is a pest on irrigated groundnut in Andhra Pradesh, Karnataka and Tamil Nadu. It is becoming increasingly important during kharif in the states of Karnataka (Dharwad), Gujarat (Junagadh) and Haryana (Hissar). Gram caterpillar has become important recently in Andhra Pradesh, Karnataka and parts of Giujarat. Red hairy cater pillar has two species; Amsacta moorei dominant in North India and A. albistriga the most dangerous and destructive to groundnut crop in South India. Termites are serious pests of groundnut in West Bengal, Uttar Pradesh, Rajasthan, Gujarat, Haryana and Punjab. Correct identification of groundnut diseases and insect pests is the first step in planning a control programme. Fortunately, symptoms/injury can be used to identify most of the diseases and insect pests in groundnut. If signs or symptoms of the disease differ considerably from what is considered to be normal, a plant sample should be submitted for study and microscopic examination. New diseases do occur and minor diseases sometimes become wide spread. Special attention should be given to diseases and insect pests that occur consistently and cause heavy losses, since growers will benefit economically from their control. Keeping in view the hard facts that : The economic capacity of the groundnut farmer is limited, The damage caused by diseases and Insect pests to groundnut crop in field is much greater than most other cereal crops, and Resistant commercial varieties of groundnut are not available emphasis has been given on effective control measures for each of the economically important diseases and insect pests.

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19. Major insect pests of groundnut-distribution-marks of identification biology-nature and symptoms of damage and management strategies of white grub, leaf miner, RHC and tobacco caterpillar; Minor insect pests of groundnut-nature and symptoms of damage and management practices of Helicoverpa, leafhoppers, thrips, aphids, pod bugs and jewel beetle.


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Nature and symptoms of damage: • The caterpillars in early stages are found in groups on the underside of the leaves and feed on them by scrapping. • Later they disperse to surrounding plants and defoliate plants. • In years of severe out breaks, field after field may have to be re-sown in the beginning of the season and later on it becomes too late even for re-sowing. • The caterpillars feed up to about September. Life cycle: • After the receipt of heavy rains in June-July, adult moths emerge from earthen cells during evening hours. They mate and commence oviposition on the same day. • The creamy or light yellowish eggs are laid in groups mostly on the under surface of leaves, on dry twigs etc. A female lays 300-1000 eggs hatch in 3-4 days.

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1. RED HAIRY CATERPILLAR (Erra gongali purugu) Red hairy caterpillars: Amsacta albistriga Arctiidae:Lepidoptera (Tiger moths) Amsacta moorei Arctiidae:Lepidoptera (Tiger moths) Black hairy caterpillars: Amsacta (Estigmene) lactinia Arctiidae:Lepidoptera (Tiger moths) • Among the hairy caterpillars, red hairy caterpillars are most injurious to agriculture throughout India. Although the red hairy caterpillars found in Southern and Northern regions of the country are said to belong to two species of the genes Amsacta, then habits, nature of damage etc., are similar. Pest of North India, Tamil Nadu, AP & KN. • They are polyphagous. • This is a serious pest and devastating pest of rainfed of Groundnut crop. • It is an endemic one and its seasonal outbreak is various tracts is largely dependent on climatic conditions and the local agricultural practices. • It appears in great numbers as regular plague after the receipt of first monsoon showers during early June. Marks of identification: • Amsacta albistriga: The adult is a medium sized moth. The forewings are white with brownish streak all over and yellow streak along the anterior margin and the hind wings with black markings. A yellowish band is seen on the head. • Amsacta moorei: The anterior marginal streak of forewings and the band on the head are red in colour. Other characters look similar to A. albistriga. • Full grown caterpillars of both these species are reddish brown with black bands on either end and have long reddish brown hairs all over the body arising on warts. Amsacta albistriga Amsacta lactinea


The larva becomes fully grown in a month, reddish brown with dense hairs all over the body. • The larvae burrow into the moist soil and pupate in earthen cell at a depth of 10-20 cm. The insect under goes pupal diapause in the soil till next year. In some places, they emerge out after a short pupae period. Management: The red as well as black hairy caterpillars are the most difficult pests to control by means of conventional insecticidal treatments, particularly if the control measures are delayed till the larvae reach the advanced and fully hairy stage at which their damage becomes more spectacular and when they generally attract serious attention. • After harvest of the affected crop, the field must be ploughed up to expose pupae (summer ploughing). • Camp fires: Dried leaves or trash may be burnt near the fields during the night as the moths are attracted by light and get killed in the fire, thus reducing their population (During June-July months they emerge from the soil during the monsoon in several successive waves, the first of which comes up soon after the onset of the rains. • The barnyard millet (Echinochloea frumentacea.) may act as strong barrier against hairy caterpillar when planted around the groundnut plot. Such a barrier reduces the cost of insecticidal use. • Erection of light traps soon after the monsoon for 20-45 days and collecting and killing of adult moths are found very effective. • Collection and destruction of egg masses and hand picking of larvae are effective in reducing the larval population. The egg masses of these pests are quite large in size and very prominent against the green background of the foliage on which they are laid. The collection of egg mass is a very practical method of effective control of the pest. • In its early stages, the larvae of the pest are found in groups on the under surface of leaves at this stage it is easily controlled by dusting Carbaryl @ 10-12 kg/acre. • When the caterpillars grow to about 1" in size, spraying endosulfan 35 EC @ 450 ml in 300 litres of water or DDVP 100% EC @ 60-80 ml in 300 litres of water or methyl parathion 50% EC @ 300 ml in 300 litres of water or Carbaryl dust @ 25-30 kg/ha. • If the pest is not controlled in the neighboring fields, the sprayed plots can be protected from the onward marching caterpillars by vegetative traps by placing shots of Jatropha (Locally Tella Nephalam/adivi amudam) or Ipomea on bunds. It has been observed that the grown up larvae are attracted to this and when they are in groups feeding on Jatropha leaves, it becomes very easy to kill them by spraying one of the insecticides recommended. • The dispersing larvae of hairy caterpillar from one field to another can be checked by digging trenches across the direction of their march, and prompt destruction of larvae dusting insecticide in trenches. • Poison baits (10 kg rice bran + 1 kg jaggery +1 liter quinolphos), prepare small balls broadcast in the fields preferably in the evening times or else prepare poison bait recommended for Spodoptera.

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2. GROUNDNUT LEAF MINER (Aaku mudata) (Surul Poochi) Aproaerema modicella (Deventer) Gelechiidae: Lepidoptera • The leaf miner is one of the major pests of groundnut crop. • Also attack soybean and redgram. • More serious on rainfed groundnut in TN, Andhra Pradesh, KN, Maharashtra and Orissa.

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• Bunch variety is severely infested. • This pest appears mostly six weeks after crop germination during September-October. • The young seedlings and older groundnut plants are attacked by this pest. • Leaf miners are favored by the hot dry conditions of the post-rainy season. Marks of identification: • The adult is a small brownish gray moth. The moth is small sized (microlepidopteran), measuring about 8-10 mm in length with a wing expanse of 20 mm. The wings are grayish with a pale white dot on each of the fore wings. • The full-grown larva is hairless, green in color with dark head and thorax.

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Life cycle: • Minute shiny white eggs are laid singly on the tender shoots, underside of leaves. Each female moth lays about 200 eggs. EP: 3 days • The full-grown larva is green in color with dark head and thorax. LP: 9-14 days. • Pupation takes place inside the leaf webbing. PP: 4 days. • Adult moths are phototropic.

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Nature & symptoms of damage: • Newly hatched larvae mine into tender leaflets between epidermal layers and feed by making galleries. • Small blister like mines which contain early instars of the dark green to brown hairless larvae are found on the leaves. • If a mine is opened, the minute caterpillar can be seen inside. • The mines enlarge as the larvae grow. • When they become too large to occupy the mine, the larvae emerge and web adjacent leaflets, web the leaves together and feed by remaining inside the webbing, and complete the life cycle. • The infestation is usually detected by the presence of small brown blotches on (or in) the leaf. Stunted growth and plants die when severely infested under dry conditions. • A severely attacked field looks 'burnt' from a distance. • Epidemics can result in total crop loss.


Management: • Set up light traps to attract/trap adults. The adult moths are attracted to light from 6.30 to 10.30 P.M. Petromax lamp placed at ground level attracts moths. • Crop rotation with non-leguminous crops would considerably reduce the leafminer population. Rotation of groundnut with soyabean and other leguminous crops should be avoided. • Chemical control is recommended if five or more active larvae per plant are found up to 30 days after seedling emergence (DAE), 10 larvae per plant at 50 DAE, or 15 larvae per plant at 75 DAE or later. • Carbaryl 50WP 0.2% Fenitrothion 50EC 400 ml in 400 litres of water/ha or Monocrotophos 0.05% are effective. • Dimethoate or quinalhos or phosalone can also be applied if groundnut leaf miners are observed over the threshold populations.

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Nature & symptoms of damage: • Grubs feed on roots and fine rootlets of sugarcane, as a result of which the plants become pale and wilted in appearance and ultimately dry up. • Grubs cut end of the stem, and the affected plants, can be easily pulled • Severely damaged plants appear as if drying from drought (clumps dryup). Life cycle: • Adults are medium sized beetle with light yellowish / brownish elytra. • Adults emerge out of soil during first monsoon showers. They are active during MayJuly months and disappear by first week of August. • Adults fly to near neem, drumstick, babul trees and feed on the leaves.

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3. WHITE GRUB / ROOT GRUB / MAY BEETLES (Vaeru purugu) Holotrichia serrata Scarabaeidae: Coleoptera Holotrichia consanguinea Scarabaeidae: Coleoptera • Root grub is a general pest feeding on the roots of a wide range of plants. • Polyphagous pest. Pulses, groundnut, sugarcane, vegetables etc. • Pest of North East Gujarat, North Rajasthan, Punjab, Haryana, Uttar Pradesh, some parts of Andhra Pradesh, Maharashtra, Karnataka & Tamil Nadu. • Serious pest in Kurnool and Anantapur districts. Marks of identification: • Adults are medium sized beetle with light yellowish / brownish elytra. • Grubs are fleshy, 'C' shaped (Scarabeiform), whitish yellow in color found close to the base of the roots. Grubs are creamy white with a brown head and reach 2” in length when full grown. They are curled up (C shape) in position.


Adults feed on existing trees on the field and mate and lay eggs in soil (up to 10cm depth). The beetles lay the eggs during April-July in small cell in the soil at a depth of 12-15 cm. A single egg per cell. • Grubs are fleshy, 'C' shaped (Scarabeiform), whitish yellow in color found close to the base of the roots. Upon examining one or more white grubs feeding 2-8 cm below the soil surface can be seen. • Pupation takes place inside the soil • Only one generation in a year. Seasonal incidence & factors of abundance: • Most abundant in light soils. • The pest is active in monsoon period. • Major pest of adsali crop. Management: For grubs: • Deep ploughing after the crop harvest. • Application phorae or quinalphos or disulfotan or carbofuran granules @ 2.5 kg a.i/ha in two equal splits i.e. a) one at planting b) one month after planting after making furrows in both sides of cane row, apply and cover with soil or • Incorporation of Lindane dust @ 60-75 kg /ha. For adult beetles: • After the emergence of adult beetles in June (after the break of monsoon), they fly to neem or other tress, hence beetles can be killed by spraying carbaryl at 5 gm / litre of water (0.25%) or methyl parathion at 0.05% concentration or endosulfan at 1.5 ml / litre of water (0.05%). • The beetles are active at night and are phototropic in the night times; hence, light traps can be setup during June in the endemic areas. Then beetles can be collected and killed to check from further generation. • Seed treatment with Chlorpyriphos (Dursban 20 EC) @ 12.5 ml/kg of seed. • Soil application of Quinolphos or Isofenphos @ 1.5 kg a.i./ha • Incorporation of dusts of BHC 10% (45 kg/ha) into the soil before transplantation or application of phorate 10% G @ 2.5 kg ai./ha in two equal splits one at planting and second month after planting. •

4. TOBACCO CATERPILLAR (Ladde purugu) Spodoptera litura (Fabricius) Noctuidae: Lepidoptera Besides groundnut, feed on castor, soybean, cotton, tobacco, castor, groundnut, tomato, cabbage, and various other cruciferous crops. • It is also known as the Cluster caterpillar, Cotton leafworm, Tobacco cutworm, and Tropical armyworm. • It is found throughout the tropical and sub-tropical parts of the world. • They are International Pests. • Wide spread in India. Pest of Andhra Pradesh, Karnataka, & Tamil Nadu. Marks of identification: • Moths are medium sized and stout bodied with forewings pale grey to dark brown in colour having wavy white markings and whitish hind wings. • The female lays eggs in masses and covers them with hair scales from her body (anal tuft hairs).

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Nature & symptoms of damage: • Castor is the most preferred host for egg laying and feeding. • They are chiefly defoliators. • The early instars are gregarious and scrape the chlorophyll content of leaf lamina giving it a papery white appearance. Larvae feed gregariously for first few days and then disperse to feed individually. • Later irregular holes are made on the leaves. • During later instars, they skeletonize the leaves leaving only veins and petioles. • During flowering and pod/capsule formation stage, the caterpillars also feed on the internal contents of capsules and cause irregular holes. Life cycle: • Pest breeds throughout the year. • Moths are active at night. • Female lays about 300 eggs in clusters. • The eggs are covered over by brown hairs and they hatch in about 3-5 days. • Larvae feed gregariously for first few days and then disperse to feed individually. • Pass through 6 instars. • Larval stage 15-30 days. • Pupation inside the soil, pupal stage 7-15 days. • Adults live for 7-10 days. • Total life cycle 32-60 days. • 8 generations in a year. Management: • Management practices are same as other bollworms in cotton (refer to cotton). • Planting castor or Sunflower plants as trap crop for egg laying and destroying eggs or first stage larvae (on skeletonised leaf) help in reducing the incidence. • Keep pheromone-litlure traps @ 2/acre. Control measures have to be taken up if Pheromone trap catches exceed 100moths over one week or one to two egg masses are seen in a meter row (10 plants) or if one or more larvae per plant is found. • Use/spray SLNPV @ 500LE/ha. • The larvae develops very thick skin once in third instar, and it becomes very difficult to manage the pest even with high dose of insecticides, and hence, it is always better to

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Larvae are variable in colour starting pale green and turning dark green to brown. Caterpillar is velvety black with yellowish green dorsal stripes and lateral white bands. A dark rings like structure is seen on anterior and posterior region in early stages.

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follow practices like collection & destruction of egg masses and neonate larval groups, erection of bird perches etc. 4% NSKE at early gregarious stages. Now a days, in case of heavy infestation of the pest, farmers prepare a bait (rice bran+jaggery+insecticide @ 10kg+1kg+1kg carbaryl or 100ml methomyl or 1L of monoctopohos or 1L chlorpyriphos in 1L water and prepare in small balls, and spray/spread in the field, since the larvae are active during night time (due to this reason, they escape the insecticide spray). Broadcast the bait on rows during evening, as the pest is nocturnal. In case the conventional insecticides fail to control the pod borers the usage of Synthetic pyrethroids is to be resorted to. Don't spray synthetic pyrethroids more than Twice, as they induce flare up of sucking pest complex.

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Nature & symptoms of damage: • The tender shoots of 2 to 2 ½ months old crop of groundnut are sometimes severely infested by this aphid. • Both nymphs and adults suck sap from tender leaves and shoots of plant causing the leaves to curl and growth to be stunted.

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5. GROUNDNUT APHID / BEAN APHID / COWPEA APHID / BLACK FLY / BEAN BLACK APHID (Paenu banka) Aphis craccivora Aphididae:Homoptera • A polyphagous pest also infests Redgram and other pulses, citrus etc. • It prefers to feed on the young shoots of leguminous plants. • A major pest on groundnut in kharif season. • Its incidence commences in the early June and reaches to peak by the end of July or early August. • Cool and humid conditions are favourable for multiplication while heavy rains wash away the aphid colonies. • Economic threshold limit is 15-20% affected plants. Marks of identification: • Adult aphid is an oblong soft bodied insect measuring about 1.8 to 2.1 mm in length. • Both winged and wingless forms are common. • Cornicles are present between 5th and 6th abdominal segments. • The body colour is dark brown. There are dark median bars on the abdomen. • The wings are thin, transparent and are held like a root over the body. • Nymphs are smaller in size and are pale green in initial instars. • The colour becomes darker in later stages.


Excrete honey dew on which sooty mould develops which interferes with photosynthetic activity of plants. • The groundnut aphid also transmits groundnut rosette virus and sometimes groundnut stunt virus diseases. • Adults and nymphs congregate mostly on growing tips and young foliage and desap which result in the chlorotic patches and leaf curl. • As flowering commences, aphids infest flower stocks and pegs thereby affecting to pod information. Life history: • A single female produces about 50 young ones and in about 8-18 days nymphs undergo four months and become adults. • Adults are winged or wingless having dark brown or olive colour. • 12-14 generations/year. Management: • Coccinellid predators such as Cocciilella sezptumpunctata, Menochiles sexmaculata would be effective in reducing the population of aphids. • Varieties which are densely hairy and with stiff leaves interfere with the build-up of aphid population. • Spray tobacco decoction (1 kg tobacco boiled in 10 lt of water for ½ an hour and make up to 30 lt + 100 g soap) • Dusting of Endosulphan 4% dust at 1 kg a.i./ha would be effective in controlling aphids. • Spray systemic insecticides like monocrotophos 0.04% or dimethoate 0.03% or phosphamidon 0.05% or malathion 0.1%.

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7. GROUNDNUT LEAF HOPPERS Empoasca kerri Empoasca fabae Empoasca flavescens Cicadellidae: Homoptera • Jassids are also called as Leaf Hoppers. • Major problem in Gujarat, Maharashtra, & Tamil Nadu. • Adults are small greenish colored insects. • Jassids fly from the plant canopy when the plant is disturbed. • Large jassid populations are seen during August and September, and February and March in groundnut growing areas in India.

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6. GROUNDNUT POD BUG Elasmolomus sordidus (Fabricius) Lygaeidae:Hemiptera • Nymphs are pinkish and adult bugs are dark brown bugs. • Lay eggs in soil. • Both nymphs and adults suck sap from developing seeds of groundnut pods in the field. • As a result, the seeds get shriveled and become rancid and give bitter taste. • The oil content and germination percentage of infested seed is also adversely affected. • Besides causing damage in the field, it continues to infest the pods in threshing yard and even in storage. • The bugs can be collected on rubbish heaps in the field threshing floors. • Dust carbaryl 10% dust • Spray malathion


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8. GROUNDNUT THRIPS Caliothrips indicus Scirtothrips dorsalis Frankliniella schultzei Thripidae: Thysanoptera • Several species of thrips attack groundnut, but only a few listed above are important. • Major pest in AP, Karnataka & Orissa. • They are polyphagous, and can infest many crops. Infestation starts from seedling stage, occurs at all stages of crop growth. • Thrips are small insects that live in the flowers and folded leaflets of groundnut. They are pale cream in color, and are usually hidden. For these reasons they are not conspicuous. • They can be present at any time of the year but are most numerous in the post-rainy season. Adults and nymphs scarp the leaf surface, hide inside the folded leaves and suck the oozing sap. The injury results in development of dull yellowish-green patches of the upper leaf surface and brown necrotic areas of the lower surface, initially resulting in white patches on the upper and necrotic patches on the lower surface of the leaves. Under heavy infestation particularly in the winter crop (November-sown in southern India), the leaves curl and plants get stunted. Apart from causing direct damage, species like Frankliniella transmit bud necrosis disease. • Each female lay 60-70 eggs single into the green plant tissue 4-6 per day. Eggs hatch in 5 days. The nymphal period last for 5 days, pupal period for 4-5 days. Several generations found in a year. • High temperature with low rainfall favours multiplication. • Insecticides effective against aphids and Jassids are also effective against thrips. • Economic threshold: 10 thrips/leaf. Revised during 2011

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High and well-distributed rainfall and low temperatures encourage jassid reproduction. Both adults and nymphs suck sap from young leaves; mostly from the lower surface. The first symptom of attack is a whitening of the veins. Yellow patches then appear, especially at the tips of leaflets. Under severe infestation, the leaf tips become necrotic in a typical 'v' shape, giving the crop a scorched appearance known as 'hopper burn' Control of the jassids with insecticides is relatively easy. There are few promising accessions possessing resistance to jassids, but most of the resistant genotypes identified are low yielders and mature 20-40 days later than common cultivars. However, cultivar NCAc 343 which possesses vertical resistance is fairly high yielder. Intercropping with pearl millet generally reduces the population of jassids in groundnut. However, groundnut-castor inter crop increases the infestation. Spraying of Monocrotophos 1.6ml per cent or Dimethoate 2ml/lit of water gave good control.

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9. POD BORER Helicoverpa armigera • Andhra Pradesh, Karnataka, Punjab & Gujarat • Mostly seen from November onwards when the groundnut plant enters into reproductive phase. • Insect is very active in post-rainy season, (October to March) which coincides with reproductive phase of groundnut crop. • Larvae damages by boring into fruits and feeds on inner contents of the pods. • The entry hole is large and typically circular. • The affected pods drop off. • IPM practices: refer cotton

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10. TERMITES Odotetermes obesus Odontotermes sp Trinervitermes biformis • West Bengal, Uttar Pradesh, Rajasthan, Madhya Pradesh, Gujarat, Haryana & Punjab • Termites penetrate and hollow out the tap root and cause wilting and premature death of the plant. • It also feed on the pod shell and scarify the pods externally rendering them more susceptible in invasion by soil fungi that can attack seeds, usually such seeds rot. • Seed dressing with insecticides such as 6.5ml of chloropyriphos /kg of seed may reduce termite damage. • Drenching with soil insecticides such as 5ml of chloropyriphos/litre of water at the localized spots will offer good control. • Digging the termitaria and destruction of the queen is most important in termite management. • Harvest the groundnuts as soon as they are matured. • Early removal of the produce from the field will reduce the chances of termite damage to pods. • More acceptable control measures would be to grow cultivars resistant to termite attack. • Seed dressing with Chloropyriphos • Drenching with Chloropyriphos (spot application)


INSECT PESTS OF SESAMUM / GINGELLY, SAFFLOWER 20. Major insect pests of sesamum-distribution, marks of identification, biology-Nature and symptoms of damage and management strategies of leaf arid pod borer and gall fly; Minor insect pests of sesamum - nature and symptoms of damage and management practices of sphinx caterpillar; Major insect pests of safflower-nature and symptoms of damage and management practices of aphid; Minor pests of safflower-nature and symptoms of damage and management practices of Helicoverpa and Spodoptera exigua.

INSECT PESTS OF SESAMUM (Nuvvulu) 1. LEAF AND POD BORER / LEAF ROLLER / LEAF WEBBER Antigastra catalaunalis Pyralidae: Lepidoptera • The species also occurs in Costa Rica, Hong Kong, India, Iran, Japan, and United Kingdom, as well as New South Wales in Australia. • This Caterpillar is a worldwide pest. • It major pest of Sesame. Specific pest of Sesamum. • The active period is July to October. Marks of identification: • Adult: Medium sized moth. The adult of this species is yellow with darker veins in the wings, and reddish splotches. The moth has a wingspan of about 2 cms. • Larvae: The larvae are pale yellow but gradually become green and develop black dots all over the body.

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Nature & Symptoms of damage: • The young caterpillars feed on leaves. • They also bore into shoots, flowers, buds and pods. • These caterpillars make shelter by rolling up young leaves and webbing them together with silk. They feed inside their shelter. • The young larvae roll together a few top leaves and feed them. • In the early stage of infestation, the plant dies without producing any branch or shoot. • In later stage of attack, infested shoots stop growing. • At flowering, larvae feed inside the flowers and on capsule formation, larvae bore into capsule and feed on developing seeds. • On larva can destroy 2-3 young plants. • The pest is also capable for sustaining itself on some wild species of sesame.


Life cycle: • Adult female moth lays about 100-130 shining flat eggs on tender parts of plant egg period 4-5 days. • Larval period 11-16 days. • Pupation in the leaf folds in white silken cocoon pupal period 4-7 days. Management: • Early sown (first week of July) kharif crop is less infested than late sown crop. • Intercrop with mungbean, pearl millet and groundnut. • Monitor using the light trap. • Collection and destruction of webbed leaves and infested pods during initial stage of the pest attack. • If the incidence is more than 1-2 larvae per plant, follow the pest control measures. • Two sprayings of endosulfan 0.07% or quinalphos 0.05% at 30 and 45 days after sowing. • Two rounds of dusting with phosalone 4% or malathion 5% dust @ 25 kg/ha at 30 and 45 days after sowing.

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2. GALL FLY Asphondylia sesame Cecidomyiidae: Diptera • The small mosquito like fly inserts the eggs into ovaries of flower buds. • Maggots are whitish, legless and with body tapering exteriorly. • The tiny maggots feed on buds and cause gall formation in place of pods without proper setting of seeds. • Maggots feed inside the floral bud, leading to formation of gall like structure which do not develop in to flower/capsules. • Maggot pupate inside the galls. • The affected buds wither and drop. • The yield of gingelly seeds get reduced in severe cases. • Monitor at the time of bud initiation, peaks appearing September to November. • Grow resistant variety like Swetha, RT-46, N-166-5 in endemic areas. • Intercrop with mungbean, pearl millet and groundnut. • Clip the galls, pick and burn the shed buds. • Conserve larval parasitoids of gall fly like Eurytoma dentipectus, Bracon hebetor Say, E. nosiotes Crawford • Dusting BHC 10% dust on the 25th, 50th and 65th day from sowing minimizes pest incidence. • Spray DDVP (Nuvan or vapona) 0.05% spraying at flowering. • Spray crop at bud initiation stage with carbaryl 50 WP at the rate of 2.5 kg or dimethoate 0.03% or endosulfan 0.07%.


3. HAWK MOTH / SPHINX CATERPILLAR Acherntia styx Spingidae:Lepidoptera • The caterpillar is a leaf feeder of gingelly. • It feeds voraciously and defoliate the plants. • The adults are recorded to visit beehives and suck the honey from the combs and cause annoyance to the bees. • Caterpillars also feed on lab lab, brinjal and jasmine. • Adult is a giant dark yellowish moth, forewings are dark brown and hind wings are yellowish with 2 black lines. Brownish giant hawk moth. Thorax with a characteristic skull marking. Abdomen has violet and yellow band. • Larva: Full grown larvae are stout, sturdy, greenish and 5 cm in length, with a prominent dorsal horn on the 8th abdominal segment. • Caterpillars feed on the leaves and defoliate the plant. • It remains active through out the crop season. • Deep ploughing exposes the pupae for predation to insectivorous birds. • Hand picking collection and destruction of caterpillars. • Two rounds of dusting with phosalone 4% or malathion 5% or endosulfan 4% dust @ 25 kg/ha, first at 30 DAS and second at 45 DAS.

4. HAIRY CATERPILLARS (Refer to Groundnut) Bihar hairy CP : Spilosoma obliqua Red Hairy CP : Amsacta albistriga, A. moori 5. STINK BUGS Nezara virudula

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6. CORIED BUGS


PESTS OF SAFFLOWER 1. SAFFLOWER APHIDS Dactynotus carthami Aphididae: Homoptera Uroleucon carthami Aphididae: Homoptera • It is a major pest of regular occurrence in Andhra Pradesh. • The incidence of the pest occurs a fortnight after crop germination and completes 4-5 overlapping generations in a crop season. • This aphid is quite large. Adults are large sized, black with pear-shaped body and conspicuous cornicles, winged or wingless. • Black aphid with conspicuous spiracles. • Nymphs are smaller and reddish brown in colour.

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Both nymphs and adults found with their head directed towards the soil. It is a serious pest of safflower. During pre-flowering stage both nymphs and adults suck the cell sap from shoot apices, peduncles, leaves and stem, secrete a honey dew like secretion on upper surface of the leaves and plant parts forming a black sooty mold which hinders photosynthetic activity resulting in stunted growth. Finally the plants dry up. About 40-50% yield losses are observed due to this insect. Infestation may occur 30-45 days old crop Avoid late sowing. If the attack is observed in the border rows take control measures. Avoid excess use of nitrogen. Maintain 2 or 3 rows of Maize and Sorghum around the fields. Release Coccinellids, chrysopids, praying mantis, Syrphids , spiders etc. Release of Chrysoperia eggs/grubs @ 1-2/plant. Chemical insecticides should only be applied if the insect population crosses the economic threshold level (ETL). Spray 750 ml Rogar per hectare or 250 ml Dimecron in 600-800 litre of water or spray Dimethoate 30 EC at 750 ml/ha,40 and 60 days after sowing or Endosulfan 0.05% or Monochroto phos 0.05%. Use 500 litres of spray mixture and 20 kg dust formulation/ ha.

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Heliothis armigera as defoliator Spodoptera exigua as defoliator


PESTS OF MUSTARD & SUNFLOWER 21. Major insect pests of mustard-distribution-marks of identification biology-nature and symptoms of damage and management strategies of aphids, sawfly and diamondback moth; Minor insect pests of mustard nature and symptoms of damage and management practices of painted bug; Major insect pests of sunflower-distribution-marks of identification-biologynature and symptoms of damage and management strategies of Helicoverpa and Spodoptera; Minor insect pests of sunflower-nature and symptoms of damage and management practices of leafhoppers, bihar hairy caterpillar and thrips.

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Nature & symptoms of damage: • Larva of mustard saw fly, attack young crop (seedling stage) by biting holes into leaves and may feed on all the leaves in heavy attacks. • Larvae feed on leaves during mornings and evenings, remaining hidden during the day time. • The pest attacks during November-December. • As a result of the feeding the leaves become full of holes. • The plants become dry or remain stunted • In case of severe infestation all the leaves are eaten up and the plant dies. Management: • Summer ploughing to destroy the pupa. • Early sowing should be done. • Maintain clean cultivation. • Apply irrigation in seedling stage is very crucial for sawfly management because most of the larvae die due to drowning effect.

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PESTS OF MUSTARD (Aavaalu) 1. MUSTARD SAWFLY Athalia lugens proxima Tenthredinidae : Hymenoptera • The mustard saw fly is found practically all over India. • It is also widely found in Indonesia, Formosa and Burma. • Its activity is generally confined to the period of October to march • In certain western regions, it is reported to be prevalent round about August. • Feeds on various cruciferous plants like mustard, Toria (Brassica compastris), cabbage, cauliflower, knocknol, turnip, radish etc. Marks of identification: • Adult is orange yellow small insect with black markings on body and have smoky wings with black veins. • The young larvae are light green in colour but gradually turn dark and fully grown they become greenish black with five lateral stripes • Damage is done by larvae which are dark green and have 8 pairs of abdominal prolegs. • Full grown larva measures 16-18 mm.


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Severe cold reduce pest growth. Give first irrigation 3-4 weeks after sowing as it reduces the larvae population. Collection and destruction of larvae in the mornings and evenings. Use of bittergourd seed oil emulsion as an antifeedant. Perilissus cingulator parasitises the larvae. Spray one litre of malathion 50 EC or 625 ml of endosulfan 35EC or quinalphos 25EC in 150-200 litres of water /ha.

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The aphid attacks generally during 2nd and 3rd week of December and continues till March. The most favourable temperature is in between 8 to 240C. 70 to 80 % humidity is favourable for faster multiplication of aphid. Rainy and humid weather help in accelerating the growth of insects. It is a serious pest of mustard.Plants are infested at all the stages. Both nymph and adults suck the sap from leaves, buds and pods. Curling may occur for infested leaves and at advanced stage plants may wither and die. Plants remain stunted and sooty molds grow on the honey dew excreted by the insects. The infected filed looks sickly and blighted in appearance. Set up yellow stick trap to monitor aphid population. Use tolerant varieties like JM-1 and RK-9501. The crop sown before 20th October escape the damage-early sowing. Destroy the affected parts along with aphid population in the initial stage. Ladybird beetles viz., Cocciniella septempunctata, Menochilus sexmaculata are most effcient pradators of the mustard aphid. Adult beetle may feed an average of 10 to 15 adults/day. The lacewing, Chrysoperla carnea predates on the mustard aphid colony. Spraying should be done only insect population is more than ETL level. Spraying should be done in evening. Spray the crop with one of the following in the flowering stage; Oxydemeton methyl, Dimethoate@ 625 - 1000 ml per ha. Revised during 2011

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2. MUSTARD APHIDS Lipaphis erysimi Aphididae:Homoptera • The mustard aphid, Lipaphis erysimi (Kaltenbach) is a serious pest of mustard in India and other tropical regions in the world. • All brassicas are infested by the pest. • Aphids are small, soft-bodied, pearl-shaped insects that have a pair of cornicles (waxsecreting tubes) projecting out from the fifth or sixth abdominal segment. • There are four nymphal stages (instars). • Wingless, female, aphids are yellowish green, gray green or olive green with a white waxy bloom covering the body. The waxy coating is more dense under humid conditions. • The winged, female, adult aphids have a dusky green abdomen with dark lateral stripes separating the body segments and dusky wing veins. • Male aphids are olive-green to brown in color.


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Egg: Diamondback moth eggs are oval and flattened. Eggs are yellow or pale green in color, and are deposited singly or in small groups of two to eight eggs in depressions on the surface of foliage, or occasionally on other plant parts. Females may deposit 250 to 300 eggs but average total egg production is probably 150 eggs. Development time averages 5.6 days. Larva: The larva is greenish with short thin hairs on the body. Full grown caterpillar measures 1 ½ and its body tapers towards both ends. The diamondback moth has four instars. If disturbed, they often wriggle violently, move backward, and spin down from the plant on a strand of silk. The larvae are colorless in the first instar, but thereafter are green. Initially, the feeding habit of first instar larvae is leaf mining, although they Revised during 2011

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3. DIAMOND BACKED MOTH (DBM) Plutella xylostella Plutellidae:Lepidoptera • Diamondback moth attacks only plants in the family Cruciferae. • Virtually all cruciferous vegetable crops are eaten, including broccoli, Brussels sprouts, cabbage, Chinese cabbage, cauliflower, collard, kale, kohlrabi, mustard, radish, turnip, and watercress. • Not all are equally preferred, however, and collard will usually be chosen by ovipositing moths relative to cabbage. • Several cruciferous weeds are important hosts, especially early in the season before cultivated crops are available. • The diamondback moth is probably of European origin but is now found throughout the Americas and in Europe, Southeast Asia, Australia, and New Zealand. • Plant damage is caused by larval feeding. Although the larvae are very small, they can be quite numerous, resulting in complete removal of foliar tissue except for the leaf veins. Caterpillars feed on under surface of leaves and bite holes in leaves and cause serious damage. Affected leaves present a withered appearance. In severe cases, the leaves are skeletonised. It also bores into pods and feeds developing seed. • Diamondback moth was long considered a relatively insignificant pest. Its impact was overshadowed by such serious defoliators as imported cabbageworm, Pieris rapae (Linnaeus), and cabbage looper, Trichoplusia ni (Hubner). However, in the 1950s the general level of abundance began to increase, and by the 1970s it became troublesome to crucifers in some areas. • Insecticide resistance was long suspected to be a component of the problem. This was confirmed in the 1980s as pyrethroid insecticides began to fail, and soon thereafter virtually all insecticides were ineffective. Relaxation of insecticide use, and particularly elimination of pyrethroid use, can return diamondback moth to minor pest status by favoring survival of parasitoids. • Adult: The moth is grayish brown with narrow wings having pale white marking anteriorly which form diamond like white patches dorsally when wings are folded over back at rest. Hence the name Diamond back moth. The moths are weak fliers, usually flying within 2 m of the ground, and not flying long distances.


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are so small that the mines are difficult to notice. The larvae emerge from their mines at the conclusion of the first instar, molt beneath the leaf, and thereafter feed on the lower surface of the leaf. Their chewing results in irregular patches of damage, and the upper leaf epidermis is often left intact. Pupa: Pupation occurs in a loose silk cocoon, usually formed on the lower or outer leaves. The duration of the cocoon averages about 8.5 days (range five to 15 days).

Management: • Installing pheromone trap to control the adult pest. • Collection and careful destruction of the larvae at gregarious stage at least twice a week. • Spray application of Malathion 0.1% or Carbaryl 0.15% or Monocrotophos 0.04% or Endosulfan 0.05% or Fenitrothion 0.05% or Pyrethrum 800 parts of water by volume. • Conserve Cotesia plutellae, as it is an important parasitoid for diamond back moth. 4. PAINTED BUG Bagrada hilaris or Bagrada cruciferarum Pentatomidae:Hemiptera • Adult bug is black with orange spots and markings called painted bug.

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Period of activity of painted bug starts from September. It is serious pest of mustard Adults and nymphs suck sap from all parts of the plant. Young plants wilt and wither as a result of the attack. Adult bugs excrete a resinous substances which spoils the pods. Quality and quantity (31% losses) of yield is affected when grown up plants are infected. Harvested crop in threshing floor is also infested. Deep ploughing so that the eggs of painted bug are destroyed. Early sowing is needed to avoid pest attack. Irrigate the crop in IV week after sowing to reduce pest attack Quick threshing of the harvested crop should be done. Burn the remains of mustard crop so that the stages of insect do not reach the next year crop. The bugs usually congregate on the leaves and stem which can be jerked to dislodge them and killed in kerosinised water. Spray the crop with 1000 ml malathion 50 EC or 1500 ml Endosulphan 35 EC or Dimethothiate 30EC 625 ml in 600- 700 liter water. All this should be applied in about 600 to 700 litres of water per ha or Endosulfan 4% dust @25 kg/ ha Revised during 2011

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PESTS OF SUNFLOWER (Proddutirugudu puvvu, Suryamukhi puvvu) 1. JASSIDS / LEAF HOPPERS Empoasca kerri Cicadellidae:Hemiptera • This insect pest has been reported from Maharashtra, Andhra Pradesh, Karnataka and Tamil Nadu. • Widely distributed • Mostly seen at seedling stage, some times found almost throughout the year. • Nymphs are pale greenish almost translucent and walk diagonally. • Adults are greenish yellow, wedge shaped with a pair of black spots on vertex and a black spot on each of the forewings.

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Female inserts eggs into leaf veins on the underside. Eggs hatch in 6-10 days and nymphal period is 7-9 days and the winged adults live for 2-3 weeks. Completes 7-8 generations in a year. Nymphs and adults suck sap usually from the under surface of the leaves and inject toxins causing curling of leaf edges and leaves turn red or brown. The leaves dry up and shed. Economic threshold; 2-3 Jassids per leaf. Spraying with any systemic insecticide. Seed treatment with imidacloprid or carbosulfan or spraying of monocrotophos protects the crop from all sucking pests including Jassids for about a month.

2. TOBACCO CATERPILLAR Spodoptera litura

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4. BIHAR HAIRY CATERPILLAR Spilosoma obliqua

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3. HEAD BORER / CAPITULUM BORER Helicoverpa armigera • The larva damages by boring into, flowers and feeds on inner contents, while feeding it thrusts it head inside the leaving the rest of its body outside. • The entry hole is large and circular. • EIL: 8-9 moths per pheromone trap/day, or 5 eggs/10 plants or 1 larva/plant or 5-10% infested fruiting bodies.


Lecture 22: (INSECT PESTS OF BRINJAL/EGG PLANT) 22. Major insect pests of brinjal-distribution-marks of identification biology-nature and symptoms of damage and management strategies of epilachna beetle, shoot and fruit borer; Minor insect pests of brinjal nature and symptoms of damage and management practices of stem borer, mealybug, aphids, leafhoppers, lacewing bug, leaf webber and red spider mite. The eggplant, aubergine, melongene, brinjal, or guinea squash (Solanum melongena) is a plant of the family Solanaceae (also known as the nightshades) and genus Solanum. It bears a fruit of the same name, commonly used as a vegetable in cooking. It is closely related to the tomato and potato and is native to Nepal, India, Bangladesh, Pakistan, and Sri Lanka.

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1. BRINJAL EPILACHNA BEETLES (Akshintala Purugu) SPOTTED BEETLE HADDA BEETLE Epilachna vigintioctopunctata (Henosepilachna vigintioctopunctata) Epilachna dodecastigma (Henosepilachna dodecastigma) Coccinellidae: Coleoptera • Commonly occurs throughout south-east Asia. • Also attack bitter gourd, bottle gourd, potato and tomato. • Beetles with 12 and 28 spots are very common. • Epilachna beetles are serious pest of brinjal, potato and tomato. • The extent of damage is at times as high as 50% or even more. • The beetles of the genus Epilachna are peculiar in the sense that they are the enemies of the farmer while the rest of the allied genera of the family coccinellidae (Lady bird beetles) are very useful friends as they are predators and they keep a number of serious pests like aphids, scales etc., under effective control. Marks of identification: • The adult beetle is small round to slightly oblong in shape measuring about 5 mm in length and 3.5 mm in width. • The underside of the beetle is flat as the upper side is convex. • The adult beetles are light brick red or pinkish, or pale brown and mottled with black spots. • The beetles have small black dots on the pronotum and the forewing (Elytra) which covers the body from the dorsal side. • These black dots are symmetrically placed in a crescent manner. • There are two species, one having 6 spots on each elytra, Epilachna dodecastigma (Epilachna 12-stigma) and another having as many as 14 spots on each elytra, Epilachna vigintioctopunctata (Epilachna 28-punctata). • Their eggs are yellowish; cigars shaped, and are deposited on leaves in groups of 5-7. • The body of grub is broad in front and narrows behind. • The grubs are yellowish in colour and stout bodied, with short spine like hair on the body, covers entire body.


Nature & symptoms of damage: • Both grubs and adults feed by scraping chlorophyll from epidermal layers of leaves, leaving the veins and veinlets, and cause characteristic skeletonized patches on the leaves and forming ladder-like windows. • The minute grubs on hatching start damaging the plant by feeding on the fresh matter of the leaf surface leaving veins and vein lets. • They confine their feeding activities generally to the under surface of leaves. • The activity of the pest is more on the lower leaves which are covered by the upper ones. • The young grubs are found in batches whereas this tendency disappears when they advance in age. • The full grown grubs are voracious eaters when compared to young stages. • They start their appearance in the field in July-August which is over wintering adults. • In severe cases even calyx of the fruit may also be infested. • Later, the affected areas on leaves dry and falloff and damage appear in the form of holes in the leaves, and plant presents an unhealthy appearance.

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Life cycle: • Female lays as many as 120 to 180 eggs, Yellowish, elongated, cigar-shaped eggs are laid in batches of 30-35 eggs, generally on lower surface of leaves, with their tips pointing, glued to the leaf surface in a vertical position. • They hatch in 2 to 4 days and spiny, yellowish grubs start feeding on the epidermis of leaves, leaving the veins and the vein lets. Grubs are yellowish with spines all over body. • The larval (grub) stage lasts for 11 to 15 days. • Pupation is on leaves, pupae are hemispherical. At that time, the full grown grub attaches the last segment of its abdomen to the leaf surface by means of a sticky secretion and the pupa is formed within the last larval skin which splits on the dorsal side. The pupae period varies from 3-6 days after which the adults emerge. • The adults are also quite voracious feeders and they feed both on the upper and lower surface of the leaf. Adult lives for one month to more than two months. • The entire life cycle is completed in 18 to 25 days during hot season and it may be as long as 50 days in winter. • All the stages of the pest are found on the plants only. • The pest has 7 generations a year.


Management: • As the beetles are found to be sluggish during the morning hours, hand picking will prove on effective control measure. • Collect and destroy egg masses • Collect and destroy skeletonized leaves with adults and grubs. • Shake plants to dislodge grubs, pupae and adults and destroy. • Insecticides of plant origin viz., Rotenone, Nicotine and Pyrethrum have been found to be quite effective. Rotenone 1% at 6-9- kg/acre. • Spray 5% Neem Seed Kernel Extract (NSKE) or 2% Neem oil at fortnightly intervals. • Spraying with DDVP 100 EC @ 0.05% to 0.1% concentration (Nursery as well as planted crop) or malathion 0.16% or methyl parathion 0.03% effectively control the pest. • If infestation is severe Endosulfan 2 ml/litre of water, Carbaryl 2g/litre of water or Dichlorvos 2ml/litre of water may be sprayed.

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2. BRINJAL SHOOT & FRUIT BORER (movvu mariyu kaaya toluchu purugu) EGG PLANT BORER Luecinodes orbonalis Pyralidae: Lepidoptera • From the point of view of extent and severity of damage, various entomologists have assigned first place to Leucinodes orbonalis. • In the early stages of the growth of the plant, the larvae of shoot and fruit borer attack and kill growing shoots. • During the fruiting season, they bore inside the fruit and by their feeding and due to presence of fecal matter, the effected fruits unfit for market. • It is also reported that in the borer infested fruits, the reduction in vitamin C content (Ascorbic acid) goes up to 68 per cent. • The pest infestation may go as high as 70% in brinjal. • Potato, tomato and many wild or cultivated solanaceous plants are alternate host plants. • Found throughout the tropics in Asia and Africa. • A major pest in India. • Its other host plants include potato, Solaum xanthoearpum, S. nigrum, potato (Solanum tuberosum) stems etc., bitter grourds, pea pods. • Active throughout the year, except in severe cold weather in North India. Marks of identification: • The moths measure about 10.0 mm in length, 20.0 mm wing-span and are medium sized, having whitish wings with large brown patches all over. • The adult moth head and thorax are blackish brown. • The young caterpillar is dull white and turns light pink as it matures. • The pinkish larva with sparingly distributed hairs on warts on the body and a brownish head measures 16-20 mm long.


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Biology • Female lays creamy-white flat eggs singly or in groups on the undersides of the leaves, on stems, flower buds, or the base of the fruit. They hatch in 3 to 5 days. • On hatching, the caterpillars start to bore into the tender, growing shoots of plants and when fruits are formed, they bore into fruits. Larval period 7-13 days. • When feeding is complete pupation (boat shaped cocoons) occurs on stems, dried shoots, or among fallen leaves. Their pupal period lasts 7 to 11 days; adult longevity is 5-7 days. • Multiple overlapping generations occur in warm climates. Management • Heavy incidence of Brinjal shoot and fruit borer cause heavy yield loss. • Remove and destroy the affected tender shoots, fallen fruits and fruits with bore holes • Avoid continuous cropping of brinjal crop (avoid monocropping) • Grow the varieties with long and narrow fruits in endemic areas • Install pheromone traps @12/ha • Spray Bacillus thuringiensis var kurstaki @ 1500 ml/ ha (750 lit of spray fluid) • Release egg parasitoid: Trichogramma chilonis @ 50,000/ ha, 4 times from 30 DAT • Spray 5% Neem seed kernel extract (NSKE) • Spray endosulfan 35 EC @ 2 ml/lit or Quinalphos 25 EC @ 1ml/lit + neem oil 2ml/lit • Avoid use of synthetic pyrethroids • Avoid using insecticides at the time of fruit maturation and harvest, and safe waiting period of 10 days to be followed between spray and harvest. • Three sprayings with carbaryl at 0.15% concentration at fortnightly intervals starting from 3 weeks after transplanting control pest, but continuous spraying of carbaryl lead to acceleration of Mite infestation; hence acaricidae should be sprayed after carbaryl sprayings.

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Nature & symptoms of damage: • No damage in nursery • Transplanted seedlings are attacked. • The caterpillar bores into petioles, midribs of large leaves and the shoots in early stage eat the internal tissues. When the infestation is on terminal shoots, they bend down and wither. • Affected shoots wither and droop. • Later the larva bore into small fruits, makes a hole, form galleries, and the affected fruits become unmarketable. • The larvae also attack the fruits making their entry under the calyx when they are young, leaving no visible signs of infestation. • Damaged flower buds are shed and fruits show circular holes. • The large holes seen on fruits are usually the exit holes of the caterpillars. • The content of vitamin C in the fruits of the brinjal is found to be reduced.


3. BRINJAL STEM BORER Euzophera perticella Pyralidae: Lepidoptera • Widely distributed all over Indian sub-continent. • It is a widespread pest of the cultivated brinjal in the plains throughout India, the most destructive pest of this crop. • Also attacks chilli, tomato and at times even potato. • Moths are medium sized. Fore wings pale or greyish brown with distinct dentate vertical black lines beyond middle of the wing. Hind wings are whitish.

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4. BRINJAL MEALY BUG (Pindi Purugu) Centrococcus insolitus Coccidohystrix insolita Pseudococcidae: Hemiptera • Polyphagous, feeding on variety of plants belonging to malvaceae, solanaceae and leguminaceae. • Adults are brown or pinkish, soft-bodies, small and oval in shape. • Body covered with white mealy wax. • They are generally present on the lower surfaces of the leaves and tender shoots. Revised during 2011

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Eggs are laid singly or in clusters on young leaves, petioles or tender shoots. Full grown caterpillars are whitish, can grow up to 16 mm. Pupation is in stem. Life cycle completes in 30-60 days. The infested plant withers up and presents a stunted growth due to the feeding activities of the caterpillar on the tissues of the stem. Generally attack at later stage of crop growth. Soon after hatching the caterpillar bores into stem near the ground level and moves downwards. Pencil-thick and woody stem is preferred. Attacked plants wither and wilt, growth is stunted and fruiting capacity is adversely affected. Avoid ratooning of brinjal crop, since woody stem is preferred by the larva. Special precaution is necessary not only to avoid the ratooning of the brinjal crop but also to uproot and burn the plants well before planting the new crop because the old plants harbor the borers and carry the infestation from crop to crop. Collect and destroy the damaged and dead plants Light trap @ 1/ha to attract and kill adults Spray endosulfan 35 EC @ 2ml/lit, Neem oil @ 2ml/lit, Quinolphos @ 2ml, Carbaryl @ 3g/litre of water Avoid using synthetic pyrethroids, which cause resurgence

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Colonies of nymphs and adults suck sap from leaves and shoots and stem. Heavy clustering of mealy bugs usually seen under surface of leaves as a thick mat with waxy secretion. They also excrete copious amount of honey dew on which the fungus sooty mold grow. Affected plants appear sick and black, resulting reduced fruiting capacity. The damage results in stunted growth of plant. Affected branch dries up.

Females have reproductive potential of laying 200-300 eggs, majority of which are female resulting in explosive outbreak. Eggs are incubated beneath their body cavity for about 4-5 days. There are three nymphal instars which last for 22-25 days. Total life period from egg to adult is 26-30 days under normal conditions Remove and burn the severely affected plants, to prevent further spread of the pest. Spray dichlorvos @ 1ml/lit or malathion @ 2ml/lit, at 15 days intervals Thorough coverage is a must.

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6. BRINJAL LEAF HOPPERS (refer under cotton jassid/pulses leaf hopper) Amrasca biguttula biguttula Amrasca (Empoasca) devastans Hishimonus (Cestius) phycitis Cicadellidae:Homoptera • Found in India, Pakistan, Philippines, Sri Lanka and Taiwan • The adult is wedge-shaped, about 2mm. Long and pale green in colour.

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5. BRINJAL APHIDS (refer cotton aphids) Aphis gossypii Rhopalosiphum pseudobrassicae Aphididae : Homoptera • Yellowish to green or black aphids congregate on the under sides of leaves and suck up sap, leaves curl downwards and discolored. • The vigor of the plant is reduced as leaves get twisted. • Plants remain stunted in severe cases.


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7. BRINJAL LACEWING BUG Gargaphia solani Urentius hystericellus Urentius sentis Tingidae: Hemiptera • Urentius hystricillus (U. achinis) and U. senstis both are specific pests of brinjal. • The eggplant lace bug has a narrow host range. Its food plants include tomato, potato, sunflower and cotton. • Common in North-Western regions of India. • The prothorax (area behind the head) of this grey and light brown bug has a hood-like projection which extends out over the body and comes to a point over the wings. • Adults (3 mm), straw colored dorsally and dark brown to blackish ventrally. The bug has a dark head, pale yellow legs, • The body appears flattened and is about 4 mm long and 2 mm wide. Revised during 2011

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The forewings have a black spot on their posterior parts. The nymphs are wingless, pale green in colour and are found in large numbers on the lower surface of the leaves. They have a characteristic way of walking diagonally in relation to their body. The nymphs and adults pierce the plant tissues and suck the cell sap by their mouthparts. Initial damage is noticed curling up along margins, followed by the yellowing of the margins of leaves, while a continued excessive infestation may result in etiolating of the leaves and subsequently stunted growth of plants. Outer leaf areas appear yellowish or burned. Leaves are extremely small and show a mosaic pattern of yellowing. Fruit-set may be very low. A little-leaf of brinjal, a virus disease is transmitted by Amrasca devastans from diseases to healthy eggplants. The adult female lays about 15 to 300 eggs in the leaf tissues and the minute nymphs emerge out of the eggs in 4 to 11 days. The nymphs moult five times. The life cycle is completed in 14 to 30 days. About 11 generation has been observed in a year, the duration of each varying from 15 to 46 days, but there is considerable overlapping. The insect is not known to hibernate and if the conditions are favorable rapid multiplication takes place. The adults are generally long-lived and can tide over during adverse climatic conditions. Rogue out infected plants destroy them. Before transplantation dip the seedlings in 0.2% carbofuran (control insect vectors). Spray with methyl parathion 0.5% or dimethoate 0.3% or endosulfan 0.5%

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Both nymphs and adults suck the sap mostly from upper surface of leaves and cause yellowing of haves in patches. Such leaves are found covered with pest excreta. The infested leaves shrivel, dry and drop down. Heavy infested plants dry completely. Brinjal lace bugs are preyed upon by lady beetle larvae and adults, spiders, and shieldshaped soldier bugs. If the bugs appear in large numbers dust endosulfan or carbaryl 2g/liter or spray dichlorvos @ 1.5ml/liter, methyl demeton @ 2ml/liter, of water.

8. LEAF ROLLER Antoba (Eublemma) olivacea Noctuidae: Lepidoptera • Common foliage pest of brinjal. • Attacks other wild solanaceous plants as well found throughout India. • Medium sized brownish white moths. Fore wings with brown tinge having a large triangular olive-green patch on outer area. Hind wings white with brownish tinge towards outer margin. • Full grown caterpillars (20 mm) are stout, purple brown and ornamented with yellow spots and hair.

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Eggs are laid on leaves. Pupation is in folded leaves. The caterpillars bore in the green shoots of the brinjal and eat the internal matter, resulting the plant to wither. The larvae also roll up the leaves and feed on the green matter while remaining inside the folds and thus lead a concealed life Ultimately the folded leaves wither and dry up. Normally the populations are not high enough to warrant any chemicals. If situations require the pest may be controlled by spraying endosulfan @2ml/litre of water.

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9. LEAF WEBBER Psara (Herpetogramma) bipunctalis Pyralidae:Lepidoptera • A minor pest found throughout India. • Also affect Amaranthus, Beet, Chenapodium etc. • Moths are straw colored having black dots and wavy lines on all the wings. • Eggs are laid in batches on under surface of leaves. • Full-grown caterpillars are stout, greenish with black spots and 24-28 mm long. • Pupation is in soil. • Life cycle is completed in about one month.

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On hatching caterpillars scrape and feed on epidermal tissues Later, larvae web the leaves with silken strands and feed on ventral surface of leaves, skeletonizing completely. Removal and destruction of webbed leaves can check the damage. If severe, spray endosulfan 2ml/litre, carbaryl 2g/litre or chlorpyriphos 2ml/litre of water.

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10. BRINJAL RED SPIDER MITE (Nalli) Tetranychus urticae Tetranychidae: Acarina • Highly polyphagous and has a world-wide distribution. • Adults are ovate, reddish brown with four pairs of legs. • Eggs are globular and whitish. Larvae (1st instar nymphs) are pinkish with three pairs of legs while nymphs (later instars) are greenish-red, look like the larvae, but have four pairs of legs. Life cycle is completed in about 20 days. • Red spider mites are found in large colonies on underside of leaves and protected by the silk webbing constructed by the female. • They are polyphagous pests. Among vegetables, brinjal, bhendi and bean are preferred mostly. • Leaves put forth a characteristic blotching appearance; become whitish then brown patches appear. Later the entire effected leaf become discolored and dried away. • Affected leaves gradually curl, get wrinkled and crumpled. • In heavy infestations, even fruits are affected. • More infestation occurs in warm and dry months. • Sulphur dust, or sprays of wettable sulphur 3-5g /litre, Ethion or Dicofol @ 3ml/litre of water are recommended.


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IPM package for Brinjal recommended by NCIPM: Nursery rising: • Always prepare raised nursery beds about 10 cm above ground level for good drainage to avoid damping off etc. • Cover the nursery beds with polythene sheet of 45 gauge (0.45 mm) thicknesses for three weeks during June for soil solarisation which will help in reducing the soil borne insects, diseases like bacterial wilt and nematodes. • However, care should be taken that sufficient moisture is present in the soil for its solarisation. • Mix 250 gm of fungal antagonist Trichoderma viride in 3 kg of FYM and leave for about seven days for enrichment of culture. • After 7 days mix in the soil in a bed of 3 sq. m. • Seed of popular hybrids like F1- 321 be sown in beds in the first week of July. • Before sowing, seed is treated with T. viride @ 4 gm/ kg. • Weeding should be done from time to time and infected seedlings should be rogued out from the nursery. Main crop • Bird perches @ 10/ acre should be erected for facilitating field visits of predatory birds. • Delta and yellow sticky traps @ 2-3/ acre should be installed for hoppers, aphids and white fly etc. • Give 2 to 3 sprays of 5 % NSKE against sucking pests. • Sprays of NSKE also bring down the borer incidence significantly. • Neem oil (2%) application is also helpful in reducing borer infestation, though marginally. • If incidence of leaf hopper and other sucking insect pests is still above ETL, then apply imidacloprid 17.8 SL @ 150 ml/ha. • Pheromone traps @ 5/ acre should be installed for monitoring and mass trapping of shoot & fruit borer Leucinodes orbonalis. Replace the lures with fresh lures after every 15-20 day interval. • Release egg parasitoid T. brasiliensis @ 1 – 1.5 lakh/ ha for shoot & fruit borer, 4-5 times at weekly interval. • Apply neem cake @ 250 kg/ ha (in two splits) in soil along the plant rows at 25 and 60 DAT for reducing nematodes and borer damage. Don’t apply neem cake when there is heavy wind velocity or temperature is above 30oC. • Clipping of borer damaged shoots and collection & destruction of damaged fruits i.e. clean cultivation helps in management of borer and phomosis disease effectively. • If the borer incidence crosses ETL (5% infestation), apply cypermethrin 25 EC @ 200 g a.i/ha (0.005%) or carbaryl 50 WP @ 3 g/litre of water or endosulfan 35 EC @ 0.07%. • Continuous cropping of brinjal leads to more borer and wilt infestation. Therefore, crop rotation with non-solanaceous crops should be followed. • Periodically collect and destroy the egg masses, larvae and adults of hadda beetle. • Rogue out the little leaf affected plants from time to time. • Use of green manure, mulching with polythene, soil application with bleaching powder will reduce the infection of bacterial wilt disease.


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Preparation of Neem Seed Kernel Extract (NSKE) 5 per cent • Fifty grams of neem seed kernel powder is required for use in one litre of water. • The neem seed kernel is powdered gently, in such a way that no oil comes out. • The powdered kernel powder is gathered in a muslin pouch and this is soaked overnight in water. • The next morning, the pouch is squeezed and the extract is taken out. • To the extract, an emulsifier is added at the rate of 1 ml/litre. • Khadi soap solution is used as an emulsifier. Khadi soap @ 1 gm per litre is soaked overnight in water and the solution is used. • The emulsifier helps the extract to stick well to the foliage. • Twenty five kilogram neem seed kernel powder is required for preparation of 500 litres of seed kernel extract, which can be used for one hectare. Preparation of Neem Oil 2 per cent • Twenty ml of neem oil is required for one litre of water. • The oil is added to the emulsifier at the rate of 1 ml per litre and stirred well. • It is very essential to add the emulsifier and mix properly. This enables the oil to mix with water well. • Khadi soap solution is used as an emulsifier. Khadi soap @ 1 gm per litre is soaked overnight in water and the solution is used. • To this, add one litre of water and stir well. • The emulsion should be used immediately, otherwise, oil droplets start floating. • Five litres of neem oil is required for preparation of 250 litres of oil spray which can be used for one hectare.


Lecture 23: (INSECT PESTS OF OKRA/BHENDI/LADIES FINGER AND TOMATO) 23. Major insect pests of okra-nature and symptoms of damage and management practices of shoot and fruit borer, leafhoppers and white flies; Minor insect pest of okra-nature and symptoms of damage and management practices of spider mite; Major insect pests of tomato-symptoms of damage and management strategies of serpentine leaf miner and fruit borer; Minor insect pests of tomato-symptoms of damage and management strategies of whiteflies.

INSECT PESTS OF OKRA/BHENDI/LADIES FINGER Insects at seedling stage: Jassids, Thrips, Aphids Insects at flowering stage: Shoot & fruit borer (Spotted borer) Insects at pod formation & development: Whitefly, Helicoverpa armigera, Spodoptera litura, Pectinophora gossypiella 1. BHENDI SHOOT & FRUIT BORER BHENDI SPOTTED BORER Earias vittela Earias insulana Noctuidae: Lepidoptera • Earias vittella and E. insulana are serious pests of bhendi. • These insects are very widely distributed. • Earias vittella is common in South East Asia. E. insulana is found in west Asia and North Africa. • These pests attack a number of other plants of the family Malvaceae among which bhendi (Abelmoschus esculentus) is of great economic importance. This pest has been reported to infest cotton, safflower, Hibiscus sp etc. • Widely distributed throughout India also found infesting fruit and a large number of wild and cultivated malvaceous plants. • Summer crop suffers more losses. • It is estimated about 69% loss in marketable yield due to attack of this insect on okra. Marks of identification:

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Earias insulana: The adult was completely green appear wings. The adult has completely green colored fore-wings. Hind wings white in color. • The body length is about 1 cm while the wing span is about 2.5 cm. • The caterpillars of both species are brownish white and have dark head and a prothoracic shield. • They have a number of black and brown spots on the body and hence the name spotted boll worm/borer.

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Earias vittella: adult has pale with appear wings with a broad greenish band in the middle.


Full grown larvae are stout and spindle shaped bearing a number of setae on each segment, and hence the name spiny bollworm/borer. • A full fed larva measures about 19 mm in length. Nature & symptoms of damage: • When the crop is young, larva bores into terminal shoots of young plants leading death of the shoots and subsequent development of side shoots and branches. • Larva also bores into the flower buds flowers. Infected parts will shed. Entrance hole is plugged with excreta. • In fruits, the larvae bore inside fruits and feed on inner tissues which become deformed in shape with no market value. • Young fruits draw flaring up symptoms and drop. • Affected fruits become unfit for consumption.

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Life history: • The moths lay 200-400 eggs singly on flower buds, branches and young leaves. Hairy part of plant is preferred for egg laying. The egg period ranges from 3-4 days. • The larval stage is completed in about 10-16 days. The pupation occurs either on plants or in the fallen leaves. Pupal period lasts for 4-9 days. • Adult stage remains for 8-22 days. • Several overlapping generations are found in a year. • Total life cycle is about 1-2 months. Seasonal dynamics: • The pest appears with the initiation of fruiting, and infestation increases and reaches its peak up to 100% after 12 weeks of sowing. • The peak incidence of fruit and shoot borer of okra was observed in the last week of August. • A positive correlation of E. vittella with minimum temperature, morning relative humidity and total rainfall and negative correlation with maximum temperature in okra. • The incidence of fruit borers usually occurs during humid conditions after the rainfall. Management: • Deep ploughing. • Clean cultivation (timely crop termination, destruction of crop residues and bhendi stalks) • Pre-planting cleanup measures during off-season (cleaning bunds, to remove alternate hosts etc.) • Select seeds from healthy and uninfected fruits. • Avoid cotton fields for bhendi cultivation, because the pests which attack cotton will also attack bhendi. • Avoid mono-cropping of bhendi year after year. • Collection and destruction of effected plant parts. The infested fruits and shoots should be removed regularly and buried deep in the soil.

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Wild bhendi, a weed act as harbour for this pest, to be removed completely. Use light traps @ 1/ha, to attract adults. Arrange bird perches @ 10/acre. Pheromone traps @ 2/ha attracts males, and lures can be changed for 40 days. Trichogramma evanescens parasitizes the eggs of spotted boll worms. Release Trichogramma @ 20,000/acre. Release Chrysoperla predator @ 4000/acre. Spray bt formulations @ 2gm/L or 5% NSKE in synchrony with early larval instars. Spray pesticides like endosulfan and chlorpyriphos with sesamum oil (synergist). Spray endosulfan (2 ml/l) or chloripyriphos (2 ml/l) or carbaryl (3 g/l) or quinalphos (2 ml/lit) effectively controls the pest. Before spraying all the affected plant parts should be removed. Two precautions are necessary to ensure success 1) the insecticidal application should be so timed as to coincide with the peak of the hatching of eggs, so that the just hatched larvae may get the fatal dose before entering the plant tissue. 2) The parasite activity in the field should be carefully assessed before the insecticidal application. Economic threshold limit is 5-10% incidence level.

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Nature & symptoms of damage: • Both nymphs and adults inflect the same type of damage. • They suck up the cell sap from the plant tissue.

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2. LEAF HOPPERS Amrasca biguttula biguttula (Ishida) Cicadellidae: Hemiptera • The jassids are popularly known as leafhoppers, particularly because their activities are mostly confined to the leaf surface. • These insects are active at night and are attracted to light in very large numbers. • The pest has a number of alternate hosts mostly belonging to the families’ malvaceae and solanaceae (cotton, brinjal, potato etc.) • Widely distributed • Mostly seen at seedling stage sometimes found almost throughout the year. Marks of identification: • A. biguttula biguttula is a small insect, the various nymphal stages of which vary from less than 1 mm to about 3 mm. • Its adult stage is subjected to seasonal changes in colour. It is reddish in winter and greenish yellow in summer. • The adult is a wedge shaped insect about 3.5 mm in length. • There is a black spot on each forewing and the black spots on the vertex. • Eggs are inserted in the leaf tissues on the upper leaf surface. • Nymphs are also pale greenish in colour like the adults but are wingless and are found in large numbers on lower surface of leaves. • Both and nymphs and adults walk diagonally.


Moreover, it is also believed that during the process of “desapping” the plant, they also inject a toxin into the plant tissue, resulting into Hopper burn. • In susceptible varieties, the jassid attack results in general mottling accompanied by the curling of the entire lamina with brown necrotic patches. • Thus, the entire photosynthetic activity of the plant is very seriously interfered with. • In case of severe infestation, plants become stunted and dry. Life cycle: • The jassid lays about 30 eggs. The eggs are usually inserted full length into the spongy parenchymatous tissue between the vascular bundles and the epidermis. The eggs hatch in 4-11 days. • The nymph moult five times and the nymphal period last for 7-21 days. • The whole life cycle is completed in a period which varies from about two weeks to more than a month and a half, depending on environmental conditions. • There are 8-10 overlapping generations. Management: • Seed treatment with imidacloprid 70WS (Confidor) @ 5g/kg seeed or thiamethaxam 25WG (Actara) @ 5g/kg seed or carbosulfan 25DS (Marshall) @ 50g/kg seed for all early sucking pests. • Intercropping with soybean / cowpea / groundnut / greengram / blackgram @ 1:2 ratio to colonize the predators such as ladybird beetles, syrphids and chrysopids. • Stem application with imidacloprid 200SL in 1:20 dilution with water at 20, 40, 60 DAS. • Soil application of Carbofuran 3 G (1 kg a.i./ha) at the time of sowing effectively controls the pest. • Spray 5% NSKE • Need based, judicious and safe application of pesticides are the most vital tripartite segments of chemical control measures under the ambit of IPM. • Spraying of imidacloprid 200SL 0.2ml/lt or acetamiprid 0.1g/lt or thiomethoxam0.2g/lt or acephate1.5g/lt or triazophos 1.5ml/lt. •

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3. BHENDI WHITE FLIES Bemisia tobaci (Gennadius) Aleyrodidae: Hemiptera • The cotton white fly is known to feed on 50 different species of plants but it becomes quite a serious pest of bhendi & cotton in certain regions of the country. • Among the cultivated crops, it attacks cotton, radish, watermelon, cucumber, chillies, brinjal, tomato, potato, tobacco, sunflower, cassava, sweet potato, pulses etc. • Highly polyphagous, generally appears from November to February. Marks of identification: • The adult is minute insect measuring about 0.5 mm in length having white or grayish wings, a yellowish body and red medially constructed eyes. • Nymphs are oval shaped, scale like, blackish with marginal bristle like fringes. • The nymphs remain stationary once they settle down.


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Life cycle: • A single female of this species lays about 70 eggs on the undersurface of leaves, mostly on the top and middle leaves of plant. Eggs are laid singly. Egg period ranges from 3-33 days. The insect can often breed parthenogenitically. The eggs are stalked and light yellow in the beginning but turn brown later on. • Nymphs moult thrice. Nymphal period lasts for 9-18 days. • There are about a dozen over lapping generations in a year. Seasonal occurrence & factors of abundance: • The maximum infestation occurs during July. • High temperature and low humidity are reported to be conducive to the multiplication of this pest. Management: • Use whitefly tolerant varieties. • Seed treatment with imidacloprid 70WS (Confidor) @ 5g/kg or thiamethaxam 25WG (Actara) @ 5g/kg seed or carbosulfan 25DS (Marshall) @ 50g/kg seed for all early sucking pests. • Intercropping with soybean / cowpea / groundnut / greengram / blackgram @ 1:2 ratio to colonize the predators such as ladybird beetles, syrphids and chrysopids. • Stem application with imidacloprid 200SL in 1:20 dilution with water at 20, 40, 60 DAS. • Keep yellow pan / sticky traps @ 25 traps/ha, for both monitoring and also mass trapping. • Locally available empty yellow palmoline tins coated with grease / vaseline / castor oil on outer surface may also be used.

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Nature & symptoms of damage: • The infestation by this pest adversely affects the physiology of the bhendi plant at all its stages of growth. • Both adults and nymphs cause severe damage. • The nymphs and adults suck the cell sap and lower the vitality of the plant. • Normal photosynthetic activity gets affected due to the growth of sooty mold on the honeydew excreted by the insect. • The vegetative growth is retarded and fruit formation is seriously hampered. • Also the shedding of the flowers is accentuated. • Besides inflecting this direct damage, the pest produces honey dew which spreads on the leaf and leads to sooty mold development and adversely affects photosynthesis. • The infested leaf gives black blotted appearance. • It is vector of Yellow Vein Mosaic Virus (YVMV).


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Spray 5% NSKE Spray any Neem product (5% Neem oil before egg laying) or 5 kg Neem Kernal extract per acre with any sticky material. Use of Synthetic pyrethroids increases the intensity of Whitefly. Spray Triazophos (2.5 ml/l) or Profenophos (2 ml/l). Soil application of carbofuran (1 kg a.i./ha) at the time of sowing and 4-5 foliar sprays of dimethoate (0.05%) or metasystox (0.02%) at an interval of 10 days effectively controls the whitefly population. Need based, judicious and safe application of pesticides are the most vital tripartite segments of chemical control measures under the ambit of IPM.

4. BHENDI RED SPIDER MITE (Nalli) Tetranychus urticae Tetranychidae: Acarina Tetranychus telarius (refer to brinjal) Other pests: 5. Red Cotton Bug Dysdercus cingulatus (refer cotton) • Both nymphs and adults puncture the tender fruits and suck the sap • The attacked fruits exhibit white to yellow spots not fit for consumption. • The effected seeds are not fit for sowing. 6. Pink bollworm Pectinophora gossypiella (refer cotton) • Affected flowers do not open fully. Such flower buds are shed. • At fruit formation stage the larva enters the fruit when it is in early instar and remains inside feeding on immature seed. • Economic threshold 5-10% incidence level and shed fruiting bodies.

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8. Okra Stemfly Melanagromyza hibisci • The maggots of this fly attack 15-30 days old plants causing nodulated galls and swellings. • At later stages, the maggots of this fly damage the petioles resulting in complete defoliation of the affected plant. • Application of carbofuran or phorate @ 1 kg a.i./ha protects the main stem from the pest attack during the seedling stage. 9. Root-Knot Nematode Meloidogyne incognita • The root-knot nematode enters the roots causing characteristic root knots or galls. • The aerial symptoms consist mainly of stunted plant growth and yellowing of leaves. • Nematode attack in the seedling stage leads to pre- and post-emergence damage resulting in reduced crop stand. • Cultural control methods such as rotation with non-host crops such as cereals, fallowing and deep ploughing 2-3 times in summer months is recommended. • Application of Nemagon (30 litres/ha) with irrigation before sowing is recommended to protect the seedling in its early stage of plant growth.

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7. Gram podborer Helicoverpa armigera (refer cotton) • The larva damages by boring into flowers and fruits and feeds on inner contents, while feeding it thrusts its head inside the fruit leaving the rest of its body outside. • The entry hole is large and circular


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IPM practices for Okra, recommended by NCIPM: • Sowing of YVMV resistant hybrids viz. Makhmali, Tulsi, Anupama-1 and Sun-40 etc. especially during kharif season of the crop. • Grow maize/sorghum on borders as a barrier/trap crop for the entry of shoot & fruit borer adults. • Set up yellow sticky and delta traps for white fly etc. • Erection of bird perches @ 10/acre in the field for facilitating bird predation. • Give two to three sprays of 5% NSKE alternating with sprays of pesticides, if needed, for leaf hopper, white fly, mites and aphids etc. • Leaf hopper, if crosses ETL (5 hoppers/plant), spray imidacloprid 17.8 SL @ 150 ml/ha. This will be effective in controlling other sucking pests as well. • Install pheromone traps @ 2/ acre for monitoring of Earias vittella moth emergence. Replace the lures after every 15-20 day interval. • Release egg parasitoid Trichogramma chilonis @ 1-1.5 lakh/ ha starting from 30-35 days after sowing, 4-5 times at weekly interval for shoot & fruit borer. • Shoot & fruit borer, if crosses ETL (5.3 % infestation), spray cypermethrin 25 EC @ 200 g a.i/ha. • Rogue out the YVMV affected plants, if any, from time to time. • Periodically remove and destroy the borer affected shoots and fruits. • Need based application of chemical pesticides viz. imidacloprid 17.8 SL @ 150 ml/ha, cypermethrin 25 EC @ 200 g a.i/ha (0.005%), quinalphos 25 EC @ 0.05% or Propargite etc. 57 EC @ 0.1 % for control of leaf hoppers, aphids, white flies, borers and mites.


PESTS OF TOMATO • • • • • • • •

Tomatoes are subject to attack by a large number of insect pests from the time plants first emerge in the seed bed until harvest. Aphids, flea beetles, leafminers, and spider mites threaten young plant-bed tomatoes. In the field, flea beetles, aphids, leafminers, stink bugs, and fruitworms cause minimal damage to the foliage. However, severe damage may result either from their feeding on the fruit or by spreading certain diseases. Greenhouse tomatoes have many of the same pests as field tomatoes. Tiny pests such as aphids, whiteflies, leafminers, and spider mites are more likely to infest greenhouse crops than beetles, grubs, or caterpillars. Occasionally moths enter through holes in screens or fans and lay eggs in the greenhouse. Even in screened greenhouses, armyworms, fruitworms, and loopers may be brought into the greenhouses on plants.

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------------------------------------------------------------------------------------------------------------1. SERPENTINE LEAF MINER Liriomyza trifolii Agromyzidae:Diptera • Pest introduced from USA in early ninetees. • Polyphagous and very widely distributed throughout India. • Adult is a tiny dark fly with yellow markings, with thin, transparent wings, females have a prominent retractile ovipositor. • Maggots are legless, pale yellow, body tapers anteriorly. • Maggot mines into the leaf and feeds on the mesophyll of the leaves making serpentine mines. • As the larva grows the diameter of the mine increases. • White long circular mines can be seen in old leaves. • Young leaves have small and thin mines in them. • The incidence is first noticed at nursery stage itself. • Pupation is in soil and the entire life cycle is completed in about 15 days. • If infestations occur at the late stage of the crop, no chemical control may be needed. • Spray triazophos @ 2ml/lt, if required at early stages. • The incidence increases with repeated sprayings of insecticides.


2. TOMATO FRUIT BORER (refer to cotton) Heliothis armigera Noctuidae: Lepidoptera • Polyphagous, attacks most of the cultivated crops, major pest of tomato, and widely distributed throughout the country. • Young larvae feed on tender foliage, while advanced stages attack the fruits. • Larva bore circular holes and usually thrust only head inside the fruit. • One larva can destroy many fruits. • External symptoms appear in the form of bored holes.

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For effective control of this pest an integrated package has to be adopted Plant two rows of marigold for every 16 rows of tomato, as a trap crop, as the female will be attracted to marigold flowers and lay eggs. To facilitate synchronous flowering, plant 40 and 25 days old seedlings of marigold and tomato, respectively, at a time. Monitor the pest through pheromone traps. Spray 5% NSKE to kill early stages larvae Place 15-20 bird perches (T shaped) per ha to invite insectivorous birds. Spray NPV @ 625 LE/ha during evening hours. Jaggery @ 1 kg, sandovit or Teepol(100 ml) are to be mixed with NPV. On need basis spray 2 ml Endosulfan, Chlorpyriphos or Quinolphos per litre of water.

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3. TOBACCO CATERPILLAR Spodoptera litura • Freshly hatched larvae feed gregariously, scraping the leaves from ventral side, later disperse, feeding voraciously at night on the foliage. • Larvae may also feed on fruits making holes of irregular shapes.


4. TOMATO WHITE FLY Bemisia tabaci (refer bhendi crop) • Vector of yellow leaf curl virus. • Nymphs and adults suck the sap on the ventral surface of leaves. • The affected leaves wrinkle and curl downwards.

5. TOMATO APHIDS Aphis gossypii (refer cotton)

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6. TOMATO MEALYBUGS (pindi purugu) Centrococcus insolitus Coccidohystrix insolita (refer brinjal) • Crawlers puncture the epidermis and start sucking the cell sap. • Nymphs secrete honey dew where sooty mold develops which hinders the photosynthetic activity. • Adults also secrete waxy materials.


Lecture 24: (INSECT PESTS OF CUCURBITS) 24. Major insect pests of cucurbits-distribution-marks of identification biology - nature and symptoms of damage and management strategies of fruit flies and pumpkin beetles; Minor insect pests of cucurbitsdistribution-marks of identification-biology-nature and symptoms of damage and management strategies of serpentine leaf miner, semilooper and pumpkin caterpillars; Insect pests of Coccinia-nature and symptoms of damage and management practices of gall fly and aphids. • Cucurbitaceae is a plant family commonly known as melons (water melon, musk melon), gourds (ridge gourd, bitter gourd, snake gourd, bottle gourd) or cucurbits (cucumbers, squashes, pumpkins) and includes crops like cucumbers, squashes (including pumpkins), luffas, melons (including watermelons). • Cucurbits are vegetable crops belonging to family Cucurbitaceae, which primarily comprises of many species consumed worldwide as food.

1. FRUIT FLIES

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MELON FLY: (Kaaaya Eega / Pandu Eega) Bactrocera (Dacus) cucurbitae Bactrocera (Dacus) zonatus Tephritidae: Diptera The melon fly, Bactrocera cucurbitae (Coquillett) is a serious pest of cultivated cucurbits. It was first reported in India by Lefroy during 1907 which reduce not only the quality of fruits and vegetables but also a serious limiting factor in the production of gourds,

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Fruit fly may refer to several organisms: Tephritidae, the family of large fruit flies, and Drosophilidae, the family of small fruit flies and vinegar flies. The dipteran family Tephritidae consists of over 4000 species, of which nearly 700 species belong to Dacine fruit flies. Nearly 250 species are of economic importance, and are distributed widely in temperate, subtropical, and tropical regions of the world. Senior-White (1924) listed 87 species of Tephritidae in India. Amongst these, the genus, Bactrocera (Dacus) causes heavy damage to fruits and vegetables in Asia. Fruit flies, Drosophila spp. are common in homes, restaurants, supermarkets and wherever else food is allowed to rot and ferment. Adults are about 1/8 inch long and usually have red eyes. The front portion of the body is tan and the rear portion is black. Fruit flies lay their eggs near the surface of fermenting foods or other moist, organic materials. Upon emerging, the tiny larvae continue to feed near the surface of the fermenting mass. Fruit flies, Bactrocera spp., are common on different kinds of fruits, melons, cucurbits etc., and are usually slightly larger than house flies, with black/brown color eyes. Their bodies are with yellow stripes. These flies lay eggs on fruits/melons below the skin of fruits, and upon emergence the maggot develops inside, tunnels and pupates outside. The fruit fly Drosophila is important for household, but the fruit fly Bactrocera is very important, which cause heavy losses in fruits and vegetables. The project entitled ‘National Integrated Fruit Fly Surveillance Project’ has been developed by the Directorate of Plant Protection, Quarantine & Storage under the Department of Agriculture & Cooperation, Ministry of Agriculture to be implemented as joint collaboration project for two years involving ICAR/State Agriculture Universities with a view to identify, establish and maintain pestfree areas in line with international/national standards for phytosanitary measures to facilitate trade in agriculture exports. The project is in force from 2004, with special reference to fruit flies in Mango growing areas, to identify pest free areas. Oriental fruit fly: Bactrocera (Dacus) dorsalis, this pest will apparently breed in all fleshy fruits. A polyphagous species and major pest recorded in Asia from 117 host species. Medium in size. Does not infest cucurbits, melons etc, but are the major pest in soft fruit crops. Melon fly: Bactrocera (Dacus) cucurbitae, over 125 species of hosts have been recorded for this species, based on extensive host surveys in Asia and Hawai'i. Plants in the family Cucurbitaceae are, however, the usual hosts. Bigger in size.

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cucumber, melon and other cucurbits to the extent that it's growing may become highly unprofitable. • It has been reported to damage 81 host plants and is a major pest of cucurbitaceous vegetables, particularly the bitter gourd, muskmelon, snap melon, and snake gourd. • Native to tropical Asia and widespread as far west as Pakistan. Originally from the Indo-Malayan region. This pest is found in Burma, Ceylon, Formosa, Guam, Hawaii, India, Japan, Java, Kenya, Malaya, Mauritius Island, Philippines, Singapore, Southern China and Timor Island. • It is the first tephritid fruit fly species established in Hawaii, USA. • The first report on melon fruit flies was published by Bezzi (1913), who listed 39 species from India. • Forty-three species have been described under the genus Bactrocera including cucurbitae, dorsalis, zonatus, oleae etc. Amongst these, Bactrocera cucurbitae (Coquillett) is a major threat to cucurbits. • The melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) is distributed widely in temperate, tropical, and sub-tropical regions of the world. • The extent of losses varies between 30 to 100%, depending on the cucurbit species and the season. • Its abundance increases when the temperatures fall below 32° C, and the relative humidity ranges between 60 to 70%. • It prefers to infest young, green, soft-skinned fruits. Marks of identification: • Adults: Melon flies are slightly larger than houseflies. The head and eyes are dark brown. Their bodies are yellowish brown with a yellow spot above the base of the first pair of legs. A yellow stripe, with curved lines on either side, is present down the center of the back. The tip of the body furthermost from the head is yellow. Wings are patterned with a thick brown band extending along the leading edge, ending in a larger brown spot at the tip.

Maggots: The larvae, or maggots, are cylindrical, elongate, narrowed, legless (apodous) and somewhat curved downward at the end and mouth hooks at the head. These maggots reach approximately 1/2 inch in length upon maturity. If distrubed, they often wriggle violently. Nature & Symptoms of damage: • The damage to crops caused by fruit flies result from 1) oviposition in fruit and soft tissues of vegetative parts of hosts 2) feeding by the larvae, and 3) decomposition of plant tissue by invading secondary microorganisms. • Maggots feed inside the fruits, but at times, also feed on flowers, and stems. Generally, the females prefer to lay the eggs in soft tender fruit tissues by piercing them with the ovipositor. A watery fluid oozes from the puncture, which becomes slightly concave with seepage of fluid, and transforms into a brown resinous deposit. Sometimes

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pseudo-punctures (punctures without eggs) have also been observed on the fruit skin. This reduces the market value of the produce. After egg hatching, the maggots bore into the pulp tissue and make the feeding galleries. The fruit subsequently rots or becomes distorted. Young larvae leave the necrotic region and move to healthy tissue, where they often introduce various pathogens and hasten fruit decomposition. Larval feeding damage in fruits is the most damaging. Mature attacked fruits develop a water soaked appearance. Young fruits become distorted and usually drop. The larval tunnels provide entry points for bacteria and fungi that cause the fruit to rot. These maggots also attack young seedlings, succulent tap roots of watermelon, and stems and buds of host plants such as cucumber, squash and others.

Biology: • Adult flies emerge from pupae during morning hours and mate at dusk. After 14 days, they lay eggs. • The female first make a cavity by sharp ovipositor and inserts slender, white color eggs, under the skin of the fruit, in clusters of 5-30, during evening hours. During egg laying, female release a gummy substance which covers and cements and makes eggs water proof. Female lays 58-95 eggs in 14-54 days. They hatch in 2 to 7 days. • The white larva is legless, and resembles an elongated cone. The mouth is at the pointed end of the body. There are 3 larval stages, or instars. The third instar is about 2/5 inch long. The entire larval stage lasts for 11-15 days. Maggots bore into pulp, forming galls. Fruits decay due to secondary bacterial infection. Larval period 3 days in summer and about three weeks in winter. • Mature maggots come out making exit holes and jump to ground and select suitable place, enter the soil and pupate. The larvae pupate in the soil at a depth of 0.5 to 15 cm. The puparium is yellowish-brown, seed-like and barrel shaped. Adults emerge in about 10

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days.

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Management: The fruits of cucurbits, of which the melon fly is a serious pest, are picked up at short intervals for marketing and self-consumption. Therefore, it is difficult to rely on insecticides as a means of controlling this pest. In situations where chemical control of melon fruit fly becomes necessary, one has to rely on soft insecticides with low residual toxicity and short waiting periods. Therefore, keeping in view the importance of the pest and crop, the melon fruit fly management could be done using local area management or wide area management. Local area management means the minimum scale of pest management over a restricted area such as at field level/crop level/village level, which has no natural protection against reinvasion. The aim of local area management is to suppress the pest, rather than eradicate it. • Bagging of fruits with 2 layers of paper bags at 2 to 3 day intervals minimizes fruit fly infestation. Cucumber fruits should be bagged at 3 days after anthesis, and the bags should be retained for 5 days for effective control. It is an environmentally safe method for the management of this pest. • Field sanitation: The most effective method. To break the reproduction cycle and population increase, growers need to remove all un-harvested fruits or vegetables from a field by completely burying them deep into the soil. Burying damaged fruits in the soil prevents adult fly eclosion and reduces population increase. • Field preparation: Slight ploughing and raking of soil after the harvest to expose the pupae which are in the soil. • Monitoring and control with parapheromone lures/cue-lure traps: The principal of this particular technique is the denial of resources needed for laying by female flies such as protein food (protein bait control) or parapheromone lures that eliminate males. There is a positive correlation between cue-lure trap catches and weather conditions such as minimum temperature, rainfall, and minimum humidity. The sex attractant cue-lure traps are more effective than the food attractant tephritlure traps for monitoring the B. cucurbitae in bitter gourd. Methyl eugenol and cue-lure traps have been reported to attract B. cucurbitae males from mid-July to mid-November. Poison baiting with fermented palm juice (one part) + saturated sugar solution (5 ml) + malathion 50 EC (5 ml) can be placed in earthen lids so as to attract and kill adult flies. A leaf extract of Ocimum sanctum, which contain eugenol (53.4%) when placed on cotton pads attract flies from a distance. A number of commercially produced attractants (Flycide® with 85% cue-lure content; Eugelure® 20%; Eugelure® 8%; Cue-lure® 85% + naled; Cue-lure® 85% + diazinon; Cue-lure® 95% + naled) are available on the market, and have been found to be effective in controlling this pest. • Chemical control: Chemical control of the melon fruit fly is relatively ineffective. However, insecticides such as malathion, dichlorvos, phosphamidon, and endosulfan are moderately effective against the melon fly. Malathion (0.5%) is more effective than carbaryl (0.2%) and quinalphos (0.2%) on bottle gourd, sponge gourd, and ridge gourd. The application of molasses + malathion and water in the ratio of 1: 0.1: 100 provides good control of melon fly. Wide area management: The methods used for a wide area management approach include male-sterile insect release, insect transgenesis, and quarantine control techniques in combination with available local area management options. The aim of wide area management is to coordinate and combine different characteristics of an insect eradication program over an entire area within a defensible perimeter.

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2. PUMPKIN BEETLES (Gummadi Penku Purugulu) RED PUMPKIN BEETLE Aulacophora (Raphidopalpa) foveicollis PLAIN PUMPKIN BEETLE Aulacophora abdominalis BLACK PUMPKIN BEETLE Aulacophora nigripennis BLACK & YELLOW PUMPKIN BEETLE Aulacophora hilaris GRAY WITH BLACK BORDER BEETLE Aulacophora concta Chrysomelidae: Coleoptera • The Pumpkin Beetle is a pest of Cucurbit crops and also feeds on some native cucurbit species. • All cucurbits damaged by this pest however, bottle gourd, red pumpkin cucumbers are heavily damaged by Red pumpkin beetle but smooth gourd and bitter gourd are relatively less damaged. • It is sometimes found in cotton but is not known to cause damage. Revised during 2011

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Sterile male technique: In this technique, sterile males are released in the fields for mating with the wild females. Sterilization is accomplished through irradiation, chemo-sterilization, or by genetic manipulation. In sterile insect programs the terms ‘sterility’ or sterile insect' refer to the transmission of dominant lethal mutations that kill the progeny. The females either do not lay eggs or lay sterile eggs. Ultimately, the pest population can be eradicated by maintaining a barrier of sterile flies. A sterile insect program is species specific, and is considered an ecologically safe procedure and has been successfully used in area-wide approaches to suppress or eradicate pest insects in entire regions such as the pink bollworm, Pectinophora gossypiella in California, the tsetse fly, Glossina austeni in Zanzibar, the New World screwworm, Cochliomyia hominivorax in North and Central America, and various tephritid fruit fly species in different parts of several continents. Chemo-sterilization (by exposing the flies to 0.5g tepa in drinking water for 24h) and gamma irradiation are the only widely tested and accepted male-sterile techniques against melon fly. The use of male-sterile and male annihilation techniques has successfully eradicated the melon fly from Japan for over 24 years. Genetic methods, Transgene based embryo-specific lethality system: Although, the sterile insect technique can be used successfully to suppress economically important pest species, conventional sterilization by ionizing radiation reduces insect fitness, which can result in reduced competition of the sterilized insects. A transgene-based, female-specific expression method of a conditional dominant lethal gene has been well tested in Drosophila melanogaster, and might be transferable to other insect pest species. Thus, the transgene based, dominant embryo lethality system can generate large numbers of competitive and vigorous sterile males, and can be used successfully in a sterile insect program. Quarantine: The import and export of infested plant material from one area or country to other non-infested places is the major mode of the spread of insect-pests. The spread of the melon fly can be blocked through tight quarantine and treatment of fruits at the import/export ports. Cold treatment at 1.1±0.6°C for 12 days disinfested Hawaiian starfruit, Averrhoa carambola, of tephritid eggs and larvae. Heat treatment of avocado fruits infested with eggs and larvae of Bactrocera cucurbitae for 40°C for 24h reduced the estimated surviving population by 99.5-100%. Import controls carried out in airports in France since 1993 on tropical fruits have revealed the presence of 12 nonEuropean and one European species of Tephritidae.

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Of the six species noticed, the commonly known red pumpkin beetle is the most destructive, next in order of importance are black pumpkin beetle. Maximum damage in caused by overwintering beetles during March to May, reaching its peak in middle of April. Marks of identification: •

Red Pumpkin Beetle Red Leaf Beetle Red Melon Beetle Aulacophora (Raphidopalpa) foveicollis

Plain Pumpkin Beetle

Black Pumpkin Beetle

Black & Yellow Pumpkin Beetle

Aulacophora abdominalis / Aulacophora indica

Aulacophora nigripennis

Aulacophora hilaris

Head, thoracic region and elytra are reddish brown colored. Elytra is single colored, with no spots.

Head, thoracic region and elytra are orange yellow colored. Elytra is single colored, with no spots

Head & thoracic region are orange yellow colored, and elytra in jet black color. Elytra is single colored, with no spots

Head & thoracic region are orange yellow colored, and elytra in yellow color with jet black color spots. Elytra is yellow colored, with two black spots on each elytra

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Nature & symptoms of damage: • Adult beetles are mainly responsible for the damage of the plant above ground, attacking on the leaves, flowers and fruits. • Adult pumpkin beetles feed on the leaves of cucurbits, chewing large holes and often leaving only the veins of the leaves. • Making holes and causing death or retardation of growth. • Young seedlings are particularly susceptible to damage as small numbers of beetles can cause total defoliation and death. • In case of heavy infestation, re-sowing is required to be done. • Early sown crop is severely affected. • Mature plants can sustain a larger amount of damage before yields start to decline. • Larvae live in the soil and feed on the roots and stem of the plant. Larval damage to the roots is usually minimal and the plants are rarely affected. • Fruits and leaves are also damaged when they come in contact with soil. • Pumpkin beetles are usually found in aggregations within the crop on both young and old leaves.


Biology: • Eggs are laid in wet soil to a depth 25 mm near the plant. A single female lays 150 to 200 eggs. • They hatch in 5-27 days depending on temperature and moisture content of the soil. Grubs after hatching, feed on roots of plants below soil surface. The grubs become full-grown within 12 to 34 days. • Pupate in soil. Pupal stage lasts for about 15-35 days. • Adults live for 20-197 days. • Thus, the life cycle is completed in 52 to 270 days. • The maximum activity of the pest is observed during hot weather and reaches its peak during the middle of April. Management: • Preventing measures like burning of old creepers, ploughing and harrowing of field after harvest of the crops are recommended for the destruction of adult, grubs and pupae. • Spray 0.05% Malathion • Dust with 5% Malathion @ 10 kg/ha. • Carbaryl is effective but should not be sprayed on flowering crops, as it is toxic to bees. • Collection and destruction of beetles in early stage of infestation. • Note: Some of the modern synthetic insecticides, DDT, BHC, Chlordane, toxaphene, heptachlor etc. belonging to chlorinated hydrocarbon group are reported to be phytotoxic to cucurbits.

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At two stages these insects cause damage to plants. Adults will attack the tender young growth of stems and leaves, and the buds and petals on mature plants. They also carry and spread the bacterial wilt organism, Erwinia tracheiphila and the cucumber mosaic virus.

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3. CUCUMBER BEETLES (Dosa penku purugulu) • Cucumber beetle is a common name given to members of two genera of beetles, Diabrotica and Acalymma, both in the family Chrysomelidae. The adult beetles are found on the leaves and flowers of cucurbits; which are plant species of the melon, cucumber and squash varieties. • The two most common pests in this family are the striped cucumber beetle and spotted cucumber beetle, which looks very much like a green ladybug. However, unlike the ladybug, cucumber beetles are not considered beneficial insects. They are sucking invaders which harm crops and ornamental plants. Striped cucumber beetle Spotted cucumber beetle Acalymma vittatum Diabrotica undecimpunctata


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Eggs are laid in clusters on the underside of host leaves, and hatch into yellowish larvae. The larvae then feed on plant roots by tunneling into the ground. In some areas, the larvae is called the "corn rootworm". Cucumber beetles can attack and overwinter in corn and bean fields; in some areas they may hide out in compost or trash piles. Eradication consists of manual removal, keeping cultivated areas free of litter and debris from infested plants, and application of pyrethrin-containing insecticides applied directly to host plants, such as Cyfluthrin or a non-systemic organphosphate insectside like malathion. Caution and strict adherence to safety instructions and directions-for-use are advised when using insecticides, especially on plants bearing produce for human or animal consumption.

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5. SNAKE GOURD SEMILOOPER (Potlaaku purugu) Plusia (Anadevidia) peponis Noctuidae:Lepidoptera • Anadevidia peponis is found in south-east Asia, including Japan, India. Taiwan and New South Wales in Australia. • The larvae feed on Cucurbitaceae species. • Found throughout South India. This insect occasionally causes appreciable damage to snake gourd. On other cucurbitaceous plants, it is only a minor pest as a rule. It is recorded on pulses. • Adult is a dark colored moth, fore wing has irregular light markings. Hind wing is of lighter colour and is darker towards the edges then towards base. A sprinkling of golden sheen is discernible in close examination, and hence is called as golden plusia.

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4. SERPENTINE LEAF MINER Liriomyza trifolii Agromyzidae:Diptera • Pest introduced from USA in early ninetees. • Polyphagous and very widely distributed throughout India. • Adult is a tiny dark fly with yellow markings, with thin, transparent wings, females have a prominent retractile ovipositor. • Maggots are legless, pale yellow, body tapers anteriorly. • Maggot mines into the leaf and feeds on the mesophyll of the leaves making serpentine mines. • As the larva grows the diameter of the mine increases. • White long circular mines can be seen in old leaves. • Young leaves have small and thin mines in them. • The incidence is first noticed at initial stage itself. • Pupation is in soil and the entire life cycle is completed in about 15 days. • If infestations occur at the late stage of the crop, no chemical control may be needed. • Spray triazophos @ 2ml/lt, if required at early stages. • The incidence increases with repeated sprayings of insecticides.


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Caterpillar grows to 30-35 mm. In the young caterpillar the head capsule and legs are black; body is light grey with scattered dark warts from which black setae arise. In the second instar each segment has dorsal and sub dorsal conical black warts, which bear a short setae each. As the caterpillar grows, the warts become white; head capsule assumes an olive green colour and the body colour turned opaque, pale green with white longitudinal stripes. The anal segment is humped. Only three pairs of prolegs are present and hence is called looper. The caterpillar is often found on the underside of the leaf which may also be lightly folded.

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Eggs are pale green globular sculptured and laid singly usually on the underside of leaves. Pupation takes place in a tough, white silken cocoon in a folded leaf. Egg period 4-5 days. Larval period is 15-20 days and pupal period 7-10 days. Handpicked if in small numbers. Spray quinalphos or malathion.

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6. PUMPKIN CATERPILLAR / CUCUMBER MOTH / MELON WORM Diaphania (Palpita) indica Pyralidae:Lepidoptera Diaphania (Palpita) hyalinata • Diaphania indica is a pest on various members of the Cucurbitae family including Cucumber and Melon (It also infests coccinia) • Found in Asia and much of tropical and sub-tropical Australia. • The adult Cucumber Moth has white translucent wings with broad dark brown borders. There is a tuft of brown hairs on the tip of the abdomen. The tuft on the end of the abdomen of the female is bushier than that of the male.


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Adult deposit oval, flattened eggs in small clusters, averaging two to six eggs per egg mass, at night on buds, stems, and the underside of leaves. Hatching occurs after three to four days. There are five instars. Total larval development time is about 14 days. Newly hatch larvae are colorless, but by the second instar larvae assume a pale yellow-green color. They construct a loose silken structure under leaves which serves to shelter them during the daylight hours. In the fifth instar, larvae have two subdorsal white stripes extending the length of the body. The stripes fade or disappear just prior to pupation, but they are the most distinctive characteristic of the larvae. The larvae fold the leaves and scrape the green matter. Principally foliage feeder. As a result of scraping by the larvae, the leaves get dried up. Prior to pupation, larvae spin a loose cocoon on the host plant, often folding a section of the leaf for added shelter. The pupal stage persists for nine to 10 days.

PESTS OF COCCINIA / SCARLET GOURD / IVY GOURD (Donda) Pyralidae:Lepidoptera Aphididae:Homoptera Curculionidae:Coleoptera Diptera:Tephritidae

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Diaphania (Palpita) indica Myzus persicae, Aphis gossypii Acythopeus cocciniae Cecidochares connexa

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Pumpkin caterpillar Aphids Stem Weevil The gall fly


Lecture 25: (INSECT PESTS OF CRUCIFERS) 25. Major insect pests of crucifers-distribution-marks of identification biology-nature and symptoms of damage and management strategies of diamondback moth, cabbage head borer, leaf webber and aphids; Minor insect pests of crucifers-nature and symptoms of damage and management practices and IPM practices of painted bug, tobacco caterpillar and butterflies. • Vegetables of the family Brassicaceae (also called Cruciferae-vegetables of mustard family) are called Cruciferous vegetables. The vegetables are widely cultivated, with many genera, species, and cultivars being raised for food production. The family takes its alternate name (Cruciferae, New Latin for "cross-bearing") from the shape of their flowers, whose four petals resemble a cross. • The cruciferous vegetables include broccoli, cabbage, Brussels sprout, cabbage, turnip, mustard, radish etc. Cruciferous vegetables have excellent cancer fighting properties due to presence of a phytochemical known as isothiocyanates, which stimulate our bodies to break down potential carcinogens. They work by preventing the transformation of normal healthy cells into cancerous cells.

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1. DIAMONDBACK MOTH (DBM) Plutella xylostella Plutellidae:Lepidoptera • Diamondback moth attacks only plants in the family Cruciferae (oligophagous). • It is sometimes called as cabbage moth. • Virtually all cruciferous vegetable crops are eaten, including broccoli, Brussels sprouts, cabbage, Chinese cabbage, cauliflower, collard, kale, kohlrabi, mustard, radish, turnip, and watercress. Not all are equally preferred, however, and collard will usually be chosen by ovipositing moths relative to cabbage. Several cruciferous weeds are important hosts, especially early in the season before cultivated crops are available. • The diamondback moth is probably of European origin but is now found throughout the Americas and in Europe, Southeast Asia, Australia, and New Zealand. • Plant damage is caused by larval feeding. Although the larvae are very small, they can be most destructive. • Diamondback moth was long considered a relatively insignificant pest. Its impact was overshadowed by such serious defoliators as imported cabbageworm, Pieris rapae (Linnaeus), and cabbage looper, Trichoplusia ni (Hubner). However, in the 1950s the general level of abundance began to increase, and by the 1970s it became troublesome to crucifers in some areas. • Insecticide resistance was long suspected to be a component of the problem. This was confirmed in the 1980s as pyrethroid insecticides began to fail, and soon thereafter virtually all insecticides were ineffective. Relaxation of insecticide use, and particularly elimination of pyrethroid use, can return diamondback moth to minor pest status by favoring survival of parasitoids. Marks of identification & Biology • Adult: The moth is grayish brown with narrow wings having pale white marking anteriorly which form diamond like white patches dorsally when wings are folded over back at rest. Hence the name Diamond back moth. The moths are weak fliers, usually flying within 2 m of the ground, and not flying long distances.


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Egg: Diamondback moth eggs are oval and flattened. Eggs are yellow or pale green in color, and are deposited singly or in small groups of two to eight eggs in depressions on the surface of foliage, or occasionally on other plant parts. Females may deposit 250 to 300 eggs but average total egg production is probably 150 eggs. Development time averages 5.6 days. Larva: The larva is greenish with short thin hairs on the body. Full grown caterpillar measures 1 ½ and its body tapers towards both ends. The diamondback moth has four instars. If disturbed, they often wriggle violently, move backward, and spin down/drop from the plant by a strand of silk. The larvae are colorless in the first instar, but thereafter are green. Initially, the feeding habit of first instar larvae is leaf mining, although they are so small that the mines are difficult to notice. The larvae emerge from their mines at the conclusion of the first instar, molt beneath the leaf, and thereafter feed on the lower surface of the leaf. Their chewing results in irregular patches of damage, and the upper leaf epidermis is often left intact. Pupa: Pupation occurs in a loose silk cocoon, usually formed on the lower or outer leaves. The duration of the cocoon averages about 8.5 days (range five to 15 days).

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Nature & symptoms of damage: • Plant damage is caused by larval feeding. • Although the larvae are very small, they can be quite numerous, resulting in complete removal of foliar tissue except for the leaf veins. • Unless populations are high, feeding damage from diamondback moth larvae on outer leaves of cabbage will have little effect on yield. • More losses may occur if feeding occurs in the heart leaves prior to heading. • Small diamondback moth larvae damage is characterized by small, irregular windows in the leaves while larger diamondback moth larvae leave an irregular, "shot-hole" pattern. • Caterpillars feed on under surface of leaves and bite holes in leaves and cause serious damage. Affected leaves present a withered appearance. • In severe cases, the leaves are skeletonised. • Diamondback moth larvae also bore into developing Brussels sprouts.


Management: • Installing pheromone trap to control the adult pest. • Collection and careful destruction of the larvae at gregarious stage at least twice a week. • Spray Bacillus formulations @ 500gm/acre. • Spray application of Malathion 0.1% or Carbaryl 0.15% or Endosulfan 0.05% or Fenitrothion 0.05% or Profenophos or Pyrethrum 800 parts of water by volume. • Conserve Cotesia plutellae, as it is an important parasitoid for diamond back moth.

2. CABBAGE BORER / CABBAGE WEBWORM (Cabbage talatoluchu purugu) Hellula undalis Crambidae: Lepidoptera • It is a widespread species which is found from Europe across Asia to the Pacific. It was first described from Italy. • The larvae feed on a wide range of plants, mainly of the Brassicaceae family. Recorded food plants include broccoli, crucifers, head cabbage, Chinese cabbage, spoon cabbage, daikon radish, horseradish, mustard, radish and turnip. • It is considered a serious agricultural pest. Revised during 2011

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Intercropping mustard in the cabbage crop 15 days prior to sowing and 25 days after planting cabbage was effective. As the pest preferred mustard, major pest population is attracted towards it, which can be destroyed by spraying the crop with Dichlorvos (1 ml/ litre of water).

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Adult moths have fawn forewings, each with sinuous pale lines and a kidney-shaped mark. The hindwings are a uniform grey darkening at the margins. The wingspan is about 2 cms. The adult female lays eggs on the growing point or on the older leaves. The caterpillar is 12-15 mm long and is whitish with pinkish-brown longitudinal stripes. The caterpillars mine the foliage, feed on the shoots and finally bore into the stem. As a result the infested plants are killed or produce side shoots, which do not form heads. It makes a web of silk around the feeding area which accumulates frass. Pupation occurs within this silken shelter. The pupa is formed in a loose cocoon of webbed-together particles of soil or other matter and is about 8 mm long, shining pale brown with a dark stripe on the back. Spray with Malathion (0.1%) or Endosulfan (0.05%) or dusting 4% Carbaryl for excellent control of the larvae. The pheromones have been determined and are used in Integrated Pest Management techniques for this species.

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3. LEAF WEBBER / CABBAGE MOTH Crocidolomia binotalis Pyralidae: Lepidoptera • It is one of the most destructive pests of cabbage.

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The moth is brown colored, with light brown colored fore-wings with dark color patterns. Eggs are laid in clusters on the undersurface of the leaves and held together by gelatinous glue. The caterpillars are green in color during early instars, and at late instars, the larvae can distinctly identified due to white/pale colored longitudinal lines. Green caterpillars web up the leaves and live inside the knotted mass. Caterpillar webs together the foliage and feeds on leaves. The leaves become skeletionised. It also feeds on flowers and pods in the case of mustard and flower heads in cabbage and cauliflower. Flowering and pod formation is adversely affected in mustard. Removal and destruction of webbed bunches Dusting the crop with Carbaryl (4%) or spraying with Malathion (0.05%) is effective.

4. CABBAGE APHIDS Brevicoryne brassicae Myzus persicae Lipaphis erysimi

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Yellowish green nymphs and adults suck cell sap and devitalize plants. Affected parts become discolored and malformed. High humidity favors rapid multiplication of this pest. The aphids are mostly observed on the lower surface of the leaves. To prevent recurrence of the pest granular insecticides like Phorate @ kg a.i./ha should be applied to soil.

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5. CABBAGE BUTTERFLY / CABBAGE WHITE Pieris brassicae Pieridae:Lepidoptera • The Large White (Pieris brassicae), also called Cabbage Butterfly, Cabbage White, or in India the Large Cabbage White, is a butterfly in the family Pieridae. • The Large White is common throughout Europe, North Africa, and Asia to the Himalayas often in agricultural areas. • The adult fore-wings are white, with black tips of both males and females, the female also has two black spots on each forewing. The underside is a pale greenish and serves as excellent camouflage when at rest. • The caterpillars are yellowish green with yellow lines and black spots and feed in groups in plain view on the leaf surface. They gain protection from predators by possessing distasteful chemicals. • The larvae of the pest after hatching from the eggs feed gregariously on the foliage and burrow into the heads. In case of severe cases the heads become completely unfit for marketing.

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The caterpillars should be handpicked and destroyed. Spraying the crop upon the emergence of the pest with Malathion (0.1%) or dusting Carbaryl (0.15%) gives excellent control of the pest.

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7. PAINTED BUG Bagrada cruciferarum Pentatomidae:Hemiptera • Serious pest of cruciferous crops and widely distributed. • The adult bug is typically shield-shaped, 5 to 7 mm long and 3 to 4 mm broad at its widest area. The upper surface has a mixture of black, white and orange markings, which gives the insect its common names harlequin bug or painted bug. • The bagrada bug lays its eggs in clusters on leaves or on the soil underneath host plants. Eggs are barrel shaped, initially white and turn orange with age. A single female can lay as many as 100 eggs within 2 to 3 weeks. The incubation period is 5 to 8 days. • Nymphs pass through five stages changing colour from bright orange to red with dark markings, gradually acquiring the colouration of the adult. Initially they do not have

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6. TOBACCO CATERPILLAR Spodoptera litura Noctuidae:Lepidoptera • Caterpillars feed on leaves and fresh growth of all cruciferous crops. • The colour of larvae may be very dark black color in carrot. • Active at night mostly and cause extensive damage. • The young caterpillars skeletonize the tender leaves. • Later on the broad leaves are completely eaten. • Before the start of head formation of cabbage, cauliflower and knolkhol, the pest can be controlled by spraying Phosphamidon 0.03% or Endosulfan 0.05% or Carbaryl at 0.15%. After head formation, spray with Malathion at 0.05% or Carbaryl at 0.15%.


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Spray Malathion at 0.1% or Dimethoate at 0.03% or Phosalone at 0.05% concentration.

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wings; wings are gradually developed as the nymphs grow. Wing pads are visible in the last instar nymph. The life cycle lasts 3 to 4 weeks and several generations may occur in a year. Bagrada bugs damage plants by feeding on young leaves. Both adults and nymphs suck sap from leaves, which may wilt and later dry. Considerable damage is caused to young plants, which may die or have the growth points severely damaged. Significant damage may also be caused to older plants. Bagrada bugs are major pests of cultivated crucifers. Severe infestations on cabbage result in stunted plants, leaves turning yellow with a rough texture, and death of the growing point. As a result, damaged plants do not produce heads or produce two or more small unmarketable heads instead of a large central head.


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IPM package recommended by NCIPM: Nursery raising • Prepare raised nursery beds about 10 cm above ground level for good drainage to avoid damping off. • Cover the beds with polythene sheet of 45 gauge (0.45 mm) thickness for three weeks before sowing for soil solarisation for reducing the soil borne pests. Sufficient moisture should be present in the soil. • Seed treatment with Trichoderma viride @ 4g/kg of seed in nursery to prevent infection of soil borne/seed borne fungal 1 kg of FYM. Mix in 1m2. It can be applied even in main field. • Spray nursery with Bt formulations @ 500gm/acre, if DBM is noticed. • Spray Dithane M-45 or Ridomyl against Downy mildew as this disease is generally seen in nursery. Main crop • Growing of two rows of mustard after every 25 rows of cabbage as a trap crop at the time of planting. This traps 80-90% of DBM population and other pests. Mustard be sprayed with Dichlorovos 0.1% as soon as it germinates. (One row of mustard is sown 15 days before cabbage planting and second 25 days after planting of cabbage. Ensure that first and last row of plot are also mustard. • Adopt wide spacing of 60 x 45 cm to reduce the chance of spread of diseases. • Use light traps for adult DBM @ 3 traps/acre. Hang a bulb over a bucket of water. Within 3-4 days most of the adults get killed. • Spray B. t (1 g/litre) if DBM 1.0/plant is noticed early or Spray NSKE 5% at primordia formation (18-25 DAP- head initiation stage - most critical stage). Repeat if DBM is >1/plant at 10-15 days interval. Maximum of 3-4 NSKE sprays in one crop season are required. When NSKE are sprayed, thorough coverage of the entire plant surface is must. • Release egg parasitoid Trichogrammatoidea bactrae at 0.5-0.75 lack/ha 3-4 times at weekly interval. (optional) • For controlling Spodoptera mechanically collect and destroy gregarious young larvae and set up traps for mass trapping. • Periodically remove and destroy disease affected leaves. If required, spray chlorothalonil/Mancozeb for Alternaria and Blitox + streptomycin for black rot. Wider spacing (60 x 50 cm) will almost eliminate any disease spread.


Lecture 26: (INSECT PESTS OF POTATO, SWEET POTATO, MORINGA) 26. Major insect pest of potato and sweet potato-distribution-marks of identification-biologynature and symptoms of damage and management strategies of tuber moth, sweet potato weevil and hairy caterpillar; Minor insect pests of potato and sweet potato - nature and symptoms of damage and management practices of tortoise beetle; Insect pest of moringanature and symptoms of damage and management practices of hairy caterpillar and bud worm.

INSECT PESTS OF POTATO • •

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In India, potato is grown in tropics as well as in sub-tropics in the cool season. About 86% of the crop is grown in the plains during under short-day conditions, about 8% in the hills during summer under long day conditions and around 6% in the plateau during the rainy season. It is a staple food of common masses in India. Though India is the largest producer of potato yet its productivity is lower as compared to potato producing countries of Europe. One of the major constraints of low productivity is the insect pests. About fifty insect pests in India have been reported attacking potato crop directly or indirectly. Potato crop is infested about by one dozen pests. The important pests of the autumn crop are jassids, aphids, tobacco caterpillar & hadda beetle. In the case of the spring crop, besides aphids, the other most important pests are cut worms.

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1. POTATO TUBER MOTH (Alu dumpa toluchu purugu) Phthorimaea operculella (Zeller) Gelechiidae: Lepidoptera • The potato tuber moth Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) is one of the most important pests worldwide. • This insect is not native of India but was first introduced in Bombay from Italy (exotic pest) about 75 years ago. In India, it is reported in Uttar Pradesh, Maharashtra State, Bihar, and Punjab. • This pest occurs especially in hot and dry climates. • The range of hosts is limited to the family Solanaceae. The most commonly attacked plants of economic importance are potato, tobacco, egg plant, and, occasionally, tomato. • It is serious both in field and storage but particularly more serious in storage. • In the plains it is active throughout the year and passes its life cycle on potato plants in the fields from November to March as a leaf miner or boring into petioles, terminal shoots and tubers underground, and from April to November in storage. • It has been said that 30-70% tubers get infested under indigenous methods of storage, but in bad case 90% damage is also reported in storage, if not properly attended. • The temperature 86 to 1000F is found most congenial for the pest activity. Marks of identification & life cycle: • The adult potato tuber moth has a narrow silver-grey body and greyish-brown wings patterned with small, dark specks. The body length is about 10 mm and the wingspan is about 12 mm. The moths are active mainly at dusk, but during the day can be seen flying sporadically within potato crops.


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The oval eggs are laid singly on the underside of potato leaves and on exposed tubers. When first laid they are pearly white, changing to yellow on maturity and to black just before hatching. Egg period: 2-6 days. The larva [caterpillar] on hatching is 1-2 mm long and grows through four instars [stages] to reach a length of 15-20 mm. Young larvae are grey or yellow-white; mature, healthy larvae are tinged with pink or green. All instars have a dark brown head. Larval period: 16-24 days.

Pupae are formed in a silken cocoon covered with soil particles and debris for camouflage. Pupation [change from a larva to a pupa] occurs among dead potato leaves, on the soil, or on stored potato tubers. Pupal period: 6-9 days. • As many as 6-8 generations may occur in the field during summer. • As the temperature drops the population declines, and the duration of the life cycle gradually lengthens. • In stored potatoes the population continues to breed all the year round, the length of the life cycle depending on storage temperature. Nature & symptoms of damage: • Both foliage and tubers suffer extensive damage. • This is caused by the larvae, which normally spend their entire lives in either one of these food sources; the only exception to this is when infested foliage is destroyed, forcing larvae to abandon it and search for tubers. • In early stage of the crop growth, the pest is injurious to the plant as leaf miner. Foliage-mining by larvae create transparent leaf blisters. Foliar infestation may be sufficiently severe to destroy the plant. • It also bores into petioles (leaf stalks) and terminal shoots. • The main danger is to tubers both in the field and under storage. • Tuber-mining larvae usually enter through the "eyes" from eggs laid nearby, and make slender, dirty-looking tunnels throughout the tuber. • The caterpillars bore the tubers and feed, as a result of damage, the potato tubers rot. • The presence of black excreta near the eye buds helps to detect its presence in the tubers. • On cutting such tubers one can find the larva in the pulp. • High levels of tuber infestation occur in the field during summer, and stored potatoes can suffer severe damage all the year round.

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Management in field: • Timely earthing-up of the crop to cover the exposed tubers helps in reducing the intensity of infestation. • Two sprays with 0.05% quinalphos, 0.05% endosulfan or 0.1% carbaryl at 15 days interval starting 60 days after planting controls the pest effectively. • Heaps of harvested potatoes should not be kept exposed in the field but covered with straw and infested tubers should be rejected before storage. • Experience with Copidosoma koehleri B. an egg-larval parasite of potato tuber worm found to reduce the pest infestation by 50-55% when released at the rate of 20,000 mummies/ha at 7 days interval starting 45 days after planting. Management in storage: • Construct potato stores away from godowns. • The potatoes should be stored in well-ventilated cool and dry places with temperature not exceeding 210C. • Walls of godown should be sprayed with 1% Malathion at an interval of three months. • Dispose infested potatoes before storage. • Cover tubers with a thin (2.5-5.0 cm) layer of dry sand, during storage. The surface of sand cover of the potatoes should be dusted with one 1% malathion dust. • In case of large quantities and where fumigation facilities are available, it is ideal to fumigate the produce with methyl bromide @ 2.5 to 5.0 kg/100 cm for 3 hours. • Fumigate the tubers with CS2 at the rate of 1kg/27 cu.m for 48 hours at 700F or ethyl bromide at the rate of 1 kg/27 cu.m for the least three hours before storage. Cs2 is reported to induce sprouting in storage. • Treatment of seed potato tubers with 5% Malathion at the rate of 125 gm/100kg is also reported to offer good protection against the pest. Such treated potatoes, however, should not be used for consumption. • If cold storage facilities are available, the produce can be safely stored for a longer period.

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2. BLACK CUTWORM / GREASY CUTWORM Agrotis ipsilon (Noctuiidae: Lepidoptera) • It is a polyphagous insect and feeds on potato, pulses, barley, oats, tobacco, peas, gram, cotton, tomato, lucerne, chillies, brinjal and other vegetables. • The cutworms are cosmopolitan insects and have been reported to occur throughout the country and particularly serious in low lying areas which remain water logged for considerable time. • The damage to the crop varies from 12 to 35%. • The moths are active at dusk and are attracted by light. • The adult is medium sized, stout, brownish-gray in color; the wingspan is about 35-50 mm (1.36-1.97 inch), with typical dagger-like marks on the wings.

A female lays 300-350 eggs (maximum 1800) in 10-15 clustors of 20-35 eggs on ventral leaf surface or moist soil. The incubation period is 4-7 days. Larval period lasts for about 3-5 weeks pupation takes place in the soil and moths emerge from pupae in 11-18 days. A generation is completed in 5-9 weeks.

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The larvae are dirty-gray, with a brown head. Full grown caterpillars are 40-48mm long dirty black in colour and have habit of coiling at slightest touch.

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Early instars cause make round holes in leaves. The caterpillars hide during the day in cracks and crevices in the soil or in debris around the plants. They feed on tender leaves of shoots during night by cutting them near the ground level. The destruction is much more than actual feeding. Occasionally, the whole standing crop can be destroyed. The larvae also make holes in stalk and enter to petioles, make tunnels, causing wilting of the plants. Feeding on roots and tubers also possible in severe cases. Heaps of green grasses may be kept at suitable interval in infested field during evening and next day mornings destroy caterpillars.

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Clean cultivation and mechanical destruction of caterpillars also help in reducing pest infestation. Irrigation also brings them on the surface and birds shall predate them. 5% Carbaryl poison bait at the rate of 25-60kg/ha controls the pest effectively.

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3. POTATO GREEN LEAF HOPPER Amrasca biguttula biguttula • Both nymphs and adults of Jassids suck plant sap. As a result of their severe attack, the leaves curl, turn pale and bronze and dry up. • Temperature 270 to 360 C and relative humidity below 75% favors the multiplication of Jassid. • Spray the crop with 300 ml of rogor 30EC (dimethoate) or metasystox 25EC (methyldemeton) or 75 ml of dimecran 85SL (phosphomidon) in 80-100 liters of water per acre. • If necessary repeat the spray after 10 days. 4. POTATO APHIDS Myzus persicae Aphis gossypii Aphis fabae • Myzus persicae causes serious damage to potato crop by transmitting leaf curl viral disease. • Spray 300 ml of Metasystox 25EC (Methyl demeton) or 200 ml of Rogar 30EC (Dimethoate) or 75 ml of Dimecran 85SL ( phosphamidon) in 100 liters of water. • In case of seed crop, apply 5 kg of Thimet 10G (phorate) to the soil at the time of the first earthing up. 5. WHITE FLY Bemisia tabaci 6. HADDA BEETLES (Refer Brinjal) Epilachna dodecastigma Epilachna vaginoctopunctata • Two species of hadda beetles attack different solanaceous vegetables, like brinjal, tomato and potato. • Both the adults and grubs cause damage by feeding on the upper surface of leaves. • The leaves present a lace-like appearance. • The infected leaves turn brown, dry up and fall off and completely skeletonize the plants. • A severe infestation may cause up to 75 percent loss in yield. • Hand packing of grubs and collection of beetles by hand nets during early stages of attack, helps in reducing the intensity of infestation. • 0.05% DDVP or endosulfan or Malathion spraying is also reported to be quite promising but have less residual effect.

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7. TOBACCO CATER PILLAR Spodoptera litura


INSECT PESTS OF SWEET POTATO (Chilakada dumpa) 1. SWEET POTATO WEEVIL (Chilakada dumpa cheema laanti erra mukku purugu) Cylas formicarius Curculionidae:Coleoptera • Cylas formicarius is considered the single most important pest of sweetpotato. • Weevil infestation ranges from 20 to 50% on many farms and can even reach to 100% depending on the season and variety. • Higher infestation occurs during dry seasons. • Sweetpotato weevil is found throughout the tropical and subtropical regions worldwide except in Africa, where it has only been reported in South Africa and coastal Kenya. • This is the only important pest in sweet potato. • Damages crop both in field and storage. • The adult weevil is 5-7 mm long, slender, smooth and hard-bodied ant-like insect with a distinct snout, metallic blue head, forewing and abdomen. The legs and thorax are reddish brown. The females differ from the males in antenna and body size. The terminal club of the female's antenna is ovoid while that of the male is cylindrical. Usually, the females are larger than the males.

The white larvae (grub) are legless with a brown sub-globular head. The abdomen is sub-conical for the first and second instars, and sub-cylindrical from third to fifth instars. Mature larvae measure 7-8 mm. • The adult female lays eggs singly in cavities excavated in vines or in storage roots, preferring the latter. The egg cavity is sealed with a protective, grey fecal plug. • The developing larvae tunnel in the vine base or storage root. • Pupation takes place within the larval tunnels. A few days after exclusion, the adult emerges from the vine or storage root. • Because the female cannot dig, she finds storage roots in which to lay her eggs by entering through soil cracks. • Hot, dry weather favors weevil development. Nature & symptoms of damage • The adult weevils feed on the tender buds, leaves, vines and storage tubers. • The larvae (grubs), the most destructive stage, feed and tunnel into the mature stems and storage roots. • The grubs bore into the stems of vines and also into the tubers in the field as well as in storage and spoil them. They become unfit for consumption. • The damage is characterized by tunnels filled with frass in the tissues. • The damage leads to thickening, drying and cracking of the stems and to secondary infection by bacteria and fungi. • Infestation of the storage roots makes them unfit for human or animal consumption, even if only a small proportion of the flesh is damaged, as the damaged tissue produces terpines giving the flesh an unpleasant odour and bitter taste. • Weevil damage increases during storage.

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Management • When sweet potato weevil populations are high, no single control method provides adequate protection. • Sanitation of the field, removing previous crop debris helps to reduce the infestation. • Adopt crop rotation. • Use of un-infested vine tips as planting material. • Apply carbaryl 20-25 kg/ha (5% dust) before planting. • Timely planting and prompt harvesting to avoid a dry period. • Filling-up of soil around the base of plants and filling of soil cracks. • Applying sufficient irrigation to prevent or reduce soil cracking. • Dipping planting material in a solution of carbofuran for 10-15 minutes prior to planting can control sweet potato weevils for the first few months of the growing season. Dipping longer than necessary can burn and kill the planting materials. • Dipping of vines before planting 0.5% fenitrothion for 5 min is also the best method. • Use pheromones • Spraying insecticides after planting is not (cost)-effective. • If necessary, spray 0.1% fenitrotthion (2ml/lit) at 15 days interval.

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2. SWEET POTATO TORTOISE BEETLE (Taabelu laanti penku purugu) Tortoise shell beetle Aspidomorpha milaris Chrysomelidae:Colepotera Green Tortoise beetle Cassida circumdata Chrysomelidae:Coleoptera • Throughout Africa, Southern China, Southeast Asia. At least four species of Aspidomorpha and eight other Chrysomelidae have been recorded in East Africa. • Sweet potato is the main host, while other Convolvulaceae especially Ipomoea triloba are alternative hosts. Other crops which have been established as alternative hosts are coffee, beet, potato and various flowers. • Tortoise beetles are widely distributed and often very common. • A number of species come under the common name of tortoise beetles or tortoiseshell beetles. • They are characterized by flattened, spiny larvae and adult beetles with broad domed oval shaped elytra. • Seldom can a serious pest, but tortoise beetles cause considerable defoliation during severe infestation. Severe damage at the vegetative and root initiation stages may reduce storage root yield. • The young larvae scrape on the surface of the leaves leaving a pale or brown translucent membrane. Older larvae produce round holes. When feeding in groups, irregular holes are formed and can totally defoliate the plant. • Adults also produce round holes in the leaves. Occasionally attacks are sufficiently severe to completely skeletonise the leaves, defoliate the plant and peel the stems. However, usually damage does not affect yield.

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Green tortoise beetle Cassida circumdata

The adult is a medium-sized golden tortoise beetle with broad transparent extension of the elytra.The elytra contains 4 of broad black spots on the transparent extension of the elytra and 19 -23 small spots for the female and 15-17 small spots for the male with a dark golden yellow dorso-median line.

The adult is a small tortoise beetle with metallic greenish yellow body. The wings have 3 irregular longitudinal black bands with lateral extension like a shield. The middle black band on inner margin of wing shares with opposite wing. The surface is pitted.

Young larvae (first to third instar) are light brown with 2 rows of 5 squares round black spots on the thoracic area and 7 rows of 2 narrow rectangular spots black spots on the abdominal region. The narrow rectangular spots split into two making 7 rows of 4 spots as the larva matures, and the colour of the body changes to golden brown. The body is surrounded with black spines.

The larva appears green, flattened, slug-like with two pairs of branched lateral fleshy green spines per segment except on meso- and metathroax which has three pairs each. The skin from the last moult is attached to a pair of subanal spines, held upright and appears dark brown. Late instars change colour from green to yellowish green, becoming more yellow near pupation.

The mated female lays around 250 eggs. The eggs are laid singly on either surface of the leaf and covered with the translucent golden brown parchment-like membrane. Hatching of eggs occurs in 4 to 7 days. The insect undergoes 5 larval instars. After each moult, the exuvium (cast skin) becomes attached to the spines and each succeeding exuvium is distinct and attached to the preceding one. These cast skins are carried by the larvae when feeding or at rest. When the larva is disturbed, it is placed over the body and is used as protective shield. The length of the accumulated exuvia becomes longer as the larva matures. The total larval development ranges from 7-26 days. The pupa becomes firmly attached with silken threads by its caudal end to either surface of the leaf. The pupal period is 4-8 days. The total life cycle ranges from 15-41 days. Longevity of adults lasts 2-29 days.

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INSECT PESTS OF MORINGA / DRUM STICK (Munaka / Munaga) 1. Moringa Hairy Caterpillar Eupterote mollifera Eupteridae:Lepidoptera upterote geminate • Major pest of drumstick in South India. • Adult: large size moth with uniform light yellowish brown in colour • Eggs laid in clusters on leaves and tender stem • Larva, Brownish in colour with densely hairy. • Larva seen in groups in tree trunks • Feed gregariously • Scraping the bark and gnawing foliage • Severe infestation leads to defoliation of the tree • Collect and destroy egg masses and caterpillars • Set up light trap @ 1 / ha to attract and kill adults immediately after rain • Use burning torch to kill congregating larvae on the trunk • Spray endosulfan 35 EC @ 2ml/ lit or carbaryl 50 WP @ 2g/lit

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2. Moringa Bud Worm Noorda moringae • Larva bores into flower buds and causes shedding • Adult Forewings: dark brown, Hind wings: white with brown border • Larva: Dirty brown with a prominent mid dorsal stripe, black head and prothoracic shield • Plough around trees to expose and kill pupae • Collect and destroy damaged buds along with caterpillar • Set up light trap @ 1/ha • Spray insecticides like Carbaryl 50 WP@ 1gm/ lit or malathion 50 EC 2 ml/ lit of water


Lecture 27: (INSECT PESTS OF CHILLI, AMARANTHUS) 27. Major insect pests of chillies-distribution-marks of identification biology-nature and symptoms of damage and management strategies of thrips, pod borer, aphids and mites; Minor insect pests of chillies-nature and symptoms of damage and management strategies of blossom midge; Major insects pests of amaranthus-nature and symptoms of damage and management practices of leaf eating caterpillar and stem weevil.

INSECT PESTS OF CHILLI

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SUCKING PESTS 1. CHILLI THRIPS (Mirapa pai mudatha) Scirtothrips dorsalis (Chilli Thrips/Castor Thrips/Yellow Tea Thrips/Assam Thrips) Caliothrips indicus Frankliniella sulphurea Thripidae:Thysanoptera • Chilli thrips, Scirtothrips dorsalis (Hood), is an important pest of crops in tropical and subtropical regions. • Chilli thrips have a very broad host range and may feed on more than 150 plant species in 40 plant families. Additional plant species may be added to the list as this pest continues to expand its geographical range. • S. dorsalis is found in almost all chilly growing areas. It is a polyphagous pest. Besides, chillies it feeds on brinjal, cotton, groundnut, castor, bottle gourd and guava, tea, grapevine, Prosopis juliflora etc. • It is more common on un-irrigated chilli crop than irrigated one. • Chilli thrips are extremely small and difficult to distinguish from other thrips species without the aid of a compound microscope. Revised during 2011

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Major commercial crop in the world, grown for vegetables and spice purpose, often as medicinal plant. Native of Mexico. In India, both green and red chilli are used in regular diet. It contains vitamin A, C and E, besides many value chemicals. Chillies are cultivated as one of the important cash crops throughout India. India is the leader in chilli production. Andhra Pradesh ranks first in India both in area and production with 2.04 lakh hectares producing 323 thousand tonnes. Though it is cultivated in all the districts in the state. Khammam (26099ha), Guntur (24819ha), Krishna (21253ha), Prakasam(20829ha), Warangal(16161) and Karimnagar (11312) are the important producing districts. The major insect’s pests of chilli can be divided into sucking pests and pod borers. It is unbelievable that almost 60% of the crop production costs are towards plant protection, especially insect pest management. Thrips and mites are important sucking pests of chilli that inflict yield loss of over 50 per cent in the event of serious infestation. Unscrupulous use of chemical insecticides to control these pests leads to pest resurgence, secondary pest outbreak, destruction of natural enemies and environmental pollution, apart from pesticide residue related health hazards. Chilli thrips and mites, characterized by relatively short life cycles, can complete several generations on a crop. Adults and nymphs of these insects suck sap from tender leaves and growing shoots. Affected leaves curl upwards and downwards resulting in damage called ‘chilli leaf curl.’ As a result of thrips infestation, leaves become smaller, thickened and brittle. Mite infestation is a characterized by elongation of petiole of older leaves and clustering of tender leaves at the tip of branches. Consequent reduction in photosynthesis and plant growth causes severe yield loss.

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Adults are pale with dark wings and less than 2 mm in length. Immature chilli thrips are also pale in color and resemble the immatures of many other thrips species. The life cycle of chilli thrips is similar to that of other common thrips species. Egg to adult development is completed within 12 to 22 days, depending on temperature and host plant species. Females insert their eggs inside plant tissue on or near leaf veins, terminal plant parts and floral structures. Eggs hatch in 6–8 days under optimal conditions, but may take longer at lower temperatures. Immature thrips pass through two larval stages (1st and 2nd instars). The first instar lasts for 2-4 days and the second instar is completed in 3-6 days. During this time larvae actively feed on tender young plant growth, consuming enough food to complete development to the adult stage. Fully-grown larvae molt into a non-feeding, prepupal stage, which may last up to 24 hours, and then pupate on protected plant parts, leaf litter or in the soil near the base of the plant. The pupal stage lasts 2–3 days. In all, chilli thrips may complete their life cycle in 12 to 22 days and females generally deposit 60 to 200 eggs in their lifetime.

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Nature & Symptoms of damage: • Infestations by chilli thrips are usually first detected by the distinctive damage caused to the host plants. Unlike flower thrips that feed primarily on pollen chilli thrips feed on various plant tissues. Feeding causes leaf, bud, and fruit bronzing (tissues turn bronze in color). • Both nymphs and adults lacerate the leaf tissues and suck the oozing spa, sometimes even the buds and flowers are attacked. • Thrips attack tender leaves and growing shoots. Rarely the older leaves are attacked. • Damaged leaves may curl upward and appear distorted. • Infested plants become stunted or dwarfed and leaves may detach from the stem at the petioles in some plant species. • Feeding may also cause buds to become brittle and drop. • Young leaves, buds and fruits are preferred, although all above ground parts of their host plants may be attacked. • Thrips also transmit “Leaf curl” or “Murda” disease in chillies. • Pest infestation will be severe in dry weather. • The damage caused by thrips ranges from 30-50%.


Management: • An integrated pest management approach is the best strategy to combat the threat from these pests. Such efforts should harmoniously combine the following tactics. • Since attack by these pests peaks during summer season, planting of the crop should be adjusted such that the vegetative stage of the crop does not coincide with summer season as pre-flowering infestation would devastate the crop. • Use tolerant varieties such as Bhaskar and Kiran. • Seed treatment with imidacloprid @ 5g/kg seed. • Soil application of phorate 10g at the rate of 1-1.5 kg per hectare before transplanting followed by spraying 500 ml of Malathion 50 EC or 500g Carbaryl 50 WP or 500g Acephate 75SP in 250 litres of water per hectare on foliage would effectively control these pests. • Use organic pesticides to control the pests. Application of 5% Neem oil, or neem oil + garlic emulsion 2 per cent may be done. • Spray new insecticides like Spinosad / imidacloprid. • Spray Carbaryl 0.15% (3g/ litre of water) or Phosalone 0.1% (3ml/litre or water) or Methyl demeton 0.05% (2ml/litre) or Acephate 1g/litre or Triazophos 1ml or Fipronil 2ml/lit of water. • For every spraying change the pesticide and spray at fortnight intervals four weeks after transplanting.

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2. CHILLI MITES (Mirapa kindi mudatha) Polyphagotarsonemus latus (Red Spider Mite/Broad Mites) (Tarsonemidae: Acarina) • Among the non-insect pests of agricultural crops, mites are probably the most notorious ones and gaining tremendous importance in the recent years due to their devastating nature. • In case of solanaceous vegetables, chillies are severely damaged by tarsonemid mite, Polyphagotarsonemus latus with yield loss up to 94% under favorable conditions. • Of late, mite has developed as a major problem in chilli cultivation. • It is making its appearance in the nursery itself after 40 days of sowing. • In the main field it gains spread during the month of November. • The affected terminal young leaves curl downward in an inverted boat shaped manner and the elongation of petioles takes place. • Infestation at early flowering stage causes bud and flower shedding, leaf curling and twisting. • Red Spider Mite is a major pest next to fruit and shoot borer in brinjal. These mites inflict heavy damage to brinjal plant by sucking the sap of leaves resulting in white speckles, which merge producing large patches. • As the population increases, mites web profusely covering the foliage on all sides, thus resulting in poor growth of crop.


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Spray Phosalone (0.1%) @ 3ml/litre (Severe conditions) Or Wettable sulphur 3g/litre of water or Dicofol (0.09%) @ 5ml/lit of water.

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There are four distinct stages in the life history of the mite viz., egg, larva, nymph and adult. The eggs are minute and oval in shape and are laid on the ventral surface of young leaves or on leaf buds. After hatching, the minute pear-shaped white larva having 3 pairs of legs move sluggishly. During the nymphal stage, transformation of larvae into adult takes place. The adults measure 0.1 mm in length and bear 4 pairs of the legs. They are yellowish green in colour and translucent in nature. The egg, larval nymphal and adult period occupies 1.5 – 2, 1.5, 1 and 8-10 days, respectively. Both sexual and arrhenotokus reproductions have been observed in mites, There is no over wintering in the mites. From the point of longevity and reproduction early winter is more favorable for adult forms and mid winter for apterous forms are observed in large number. They are responsible for spreading the infestation from plant to plant and establish new colonies. Nymphs and adults suck sap from leaves. Affected leaves curl downward along the margins of the leaf and attain an inverted boat shape. Leaf petioles elongated and small leaves serrated and looks like bunchy appearance. Leaves turn to dark grey in colour and reduce leaf sheath, stops flowering and considerable yield reduction. In severe cases fruit wall becomes hard and white strips appears on the fruit.

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4. WHITE FLY (Tella doma) Bemisia tabaci (refer cotton for all details) • Highly polyphagous generally appears from November to February. • The insect breeds throughout the year and the female lays stalked yellow spindle shaped eggs singly on the lower surface of the leaf. • Eggs hatch in about a week's time • The Nymphal stage remains attached on the lower side of leaves and takes about 4 weeks to complete development. • Number of generations varies between 12-15 per year. • Nymphs are Oval, Scale like and remain attached to the leaf surface. Adults are tiny, moth like with yellowish body and wings coated with milky white waxy powder.

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3. CHILLI APHIDS (Paenu Banka) Aphis gossypii Myzus persicae • Generally seen when the plants are in reproductive phase. • The pest is active from May to November. • Adults live for 2-3 weeks and produce 8-22 nymphs per day. • Both winged and wingless forms breed parthenogenetically. • The Nymphal period lasts for about 7-9 days. • It has 12-14 generations per year. • Multiplying fast during December-January. • Occurs mainly in dry and cloudy weather cool and humid conditions are favourable for multiplication while heavy rains wash away the aphid colonies. • Appear on the tender shoots, leaves and on the lower surface of the leaves. • Suck the sap and reduce the vigour of the plant. • Secrete sweet substances which attract ants and develop sooty mould. • The pods that develop black colour due to sooty mould lose quality and fetch low price. • The yields are also reduced by aphids directly and more through the spread of virus diseases (chilli veinal mottle virus) acting as vectors indirectly. • Spray with 0.1% Dimethoate or Methyl demeton (2 ml/litre of water) or Monocrotophos 1.5ml or Acephate (1g/litre of water) • Spray with alternate chemicals at 10 days interval till the end of aphid population checked. • The winged forms of aphids migrate from one field to another rapidly. • Hence, spraying is to be done as far as possible within a day or two by all the cultivators of particular locality.


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Nymphs and adults suck the sap usually from the under surface of the leaves and excrete honey dew causing contamination of the fruit. Leaves appear sickly and get coated with sooty mold. It also transmits the leaf curl virus.

Whiteflies can be effectively attracted and controlled by yellow sticky traps, which are coated with grease and sticky oils. Spray Triazophos 2ml/litre of water or Profenophos 2 ml/litre of water. Use of Synthetic Pyrethroids increases the intensity of Whitefly. Spray any Neem product (5% Neem oil before egg laying) or 5 kg Neem Kernel extract per acre with any sticky material.

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All the pod borers are nocturnal in habit and can be seen during day time also in the early stages. It is easy to control when they are seen in numbers on the same plant feeding on leaves making small holes. Spray Chlorpyriphos 2.5ml/litre, Quinolphos 2ml/litre, Endosulphan 2ml or Carbaryl 3gm or Thiodicarb 1gm or Acephate 1g/litre of water are recommended. Keep Pheromone traps (2/acre) in the field to attract the male moths by which the intensity of pod borers in the environment can be known. Revised during 2011

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FRUIT BORERS / POD BORERS 5. TOBACCO CATER PILLAR (Pogaku ladde purugu) Spodoptera litura (Refer to cotton, castor for other details) • In chilli the caterpillar mostly damages the fruits by boring into it. • This coincides with post rainy season viz., November onwards. • After December, particularly after heavy rains, heavy infestation develops. • Fruit borers are polyphagous and appear on chilli crop both in vegetative phase and at the time of pod formation. • Among the pod borers, Spodoptera litura is major and does maximum damage to chilli crop. • The larvae of second and third instar enter chilli pods by making a hole near calyx and feed on chilli seed. • The affected pods drop off or develop white colour on drying.


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Poison baiting with 5kg bran, 500gms Jaggery & 500gms carbaryl or 500ml Monocrotophos or chlorpyriphos mixed with water, small pellets should be made & applied in the evening times in the field. In the right times larvae come out, eat and die is promising against grown up caterpillars which withstand contact insecticide sprays. In case the conventional insecticides fail to control the pod borers the usage of Synthetic pyrethroids is to be resorted too. Don't spray synthetic pyrethroids more than twice, as they induce flare up of sucking pest complex. Refer cotton for IPM package recommended for tobacco cater pillar.

6. CHILLI POD BORER (Patcha purugu) Helicoverpa armigera • Mostly seen from November onwards when the chilli enters into reproductive phase. • Insect is very active in post-rainy season, (October to March) which coincides with reproductive phase of chilli crop. • Larvae damages by boring into fruits and feeds on inner contents of the pods. • The entry hole is large and typically circular. • The affected pods drop off.

7. CHILLI BLOSSOM MIDGE (Pootha purugu) Contarania lycopersici Cecidomyiidae: Diptera Contarania maculipennis Contarania solani • The blossom midge has a wide host range spanning at least six plant families, including the flower buds of orchid, plumeria, hibiscus, pikake (jasmine), white mustard, tomato, eggplant, pepper, potato, bitter melon, and other vegetables and ornamentals. • Blossom midge maggots feed inside unopened flower buds, causing deformed, discolored buds and blossoms, and in severe infestations, premature bud or blossom drop. As many as 30 maggots may be found infesting a single bud. • The adult blossom midge is very tiny (about the thickness of a nickel in length); males are slightly smaller than females. The adult is somewhat mosquito-like, with typical fly features, and survives for only 4 days. • The maggots feed on fluids drawn by their rasping mouthparts from the damaged flower bud tissue. The maggots are white when newly hatched, becoming yellow, with a pink tinge as they age. As they mature, the maggots are capable of flipping themselves several inches into the air to exit the buds and burrow into the soil to pupate, like other ground-pupating fly larvae such as the melon fly and oriental fruit fly. Revised during 2011

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Refer cotton for IPM package recommended for Helicoverpa armigera.

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Sanitation is the most important management practice for the blossom midge. Remove and destroy all dropped buds and infested buds still on the plant. Place infested flower buds in a plastic bag or a sealed container to prevent escape of maggots. Due to the blossom midge’s wide range of hosts, avoid planting possible alternate hosts around the crop area. A certain variety of tomato was observed to be more susceptible to blossom midge infestation due to its flower structure which facilitates ovipositing. Host plant varieties in which petals remain tightly fitted until the bud is almost ready to open may reduce susceptibility.

8. ROOT GRUB Holotrichia consanguine (Refer groundnut crop) PESTS OF AMARANTHUS (Thotakoora) 1. LEAF CATERPILLAR Hymenia recurvalis (Spoladea recurvalis) Pyralidae: Lepidoptera • Other hosts include spinach, beet, cotton, maize, and soybean. • Adult Small, black coloured, moth with slender body.Wings dark brown in colour with white wavy markings • Greenish with white lines and black crescents on thorax below the lateral lines.

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Web the leaves with silken threads and feed within. Webbed leaves become devoid of chlorophyll and dry up. Collect and destroy affected plant parts with caterpillars Set up light trap @ 1/ha to attract and kill the adults Spray malathion 50 EC 1 ml/ lit or endosulfan 35 EC @ 1 ml/ lit

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2. AMARANTHUS WEEVIL Hypolixus truncatulas Curculionidae: Coleoptera • Adult weevil, Ash greys in colour with brown elytra and has a very long snout. • Grub, stout, curved, legless and white in colour. • Irregular zig-zag tunnels in the pith region filled with excreta. • Gall like thickening and longitudinal splitting of stem. • Suppression of root and leaf production • Collect and destroy wild amaranthus hosts in the vicinity of cultivated crop • Collect and destroy affected plant parts along with grubs and adults • Spray insecticides like malathion 50 EC 2 ml/ lit or endosulfan 35 EC @ 1ml/ lit after the harvest of leaf.


Lectures: 28-29 (INSECT PESTS OF MANGO) 28. Major insect pests of mango-distribution-marks of identification biology-nature and symptoms of damage and management strategies of leafhoppers, stem borer, nut weevil and fruit fly. 29. Minor insect pests of mango-nature and symptoms of damage and management practices of stem borer, mealybug, aphids, leaf webber and red spider mite.

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NATIONAL FRUIT OF INDIA KING OF FRUITS

Mango, cultivated in India since times immemorial, is regarded as the National Fruit of the country. Described as the "Food of the Gods", in the sacred Vedas, the fruit is grown almost in all parts of India, except the hilly areas, but is mainly available in the summer season only. There are more than 100 varieties of mangos in India, in a range of colors, sizes, and shapes. The common names used in context of the fruit are, Mangot, Manga, and Mangou. The exact origin of the term 'mango' is not known. It is believed to have come from the Portuguese term 'manga', which is probably from Malayalam 'manga'. Mango finds a mentioned in the Indian history as well. In fact, the famous poet Kalidasa is known to have sung its praises. Apart from that, ancient Greek King Alexander the Great and Chinese pilgrim Hieun Tsang have been said to have savored its taste. Historical records also mention the instance of Mughal King Akbar planted 100,000 mango trees in Darbhanga, known as Lakhibagh. Mangos, liked for their sweet juice and bright colors all around the world, are known to be rich in vitamin A,C, and D. A large number of mango varieties can be found in India. the most popular ones include 'Alphonso' (also called 'Hapoos'), 'Amrapali', 'Bangalora', 'Banganapalli' (also known as 'Benishaan'), 'Bombay', 'Bombay Green', 'Chausa', 'Chinna Rasalu', 'Dashaheri' ('Daseri'), 'Fazli', 'Fernandian', 'Gulabkhas', 'Himayath' (a.k.a. 'Imam Pasand'), 'Himsagar', 'Jehangir', 'Kesar', 'Kishen Bhog', 'Lalbaug', 'Langda' ('Langra'), 'Mallika', 'Mankurad', 'Mulgoa', 'Neelam', 'Pairi', 'Pedda Rasalu', 'Rajapuri', 'Safeda', 'Suvarnarekha', 'Totapuri', 'Vanraj' and 'Zardalu'. Frost-free climate is best for the growth of Mangos. If temperatures drop below 40° F, even for a short period, the flowers and small fruits already grown on the tree can get killed. In other words, warm and dry weather is required for the cultivation of the fruit. This is it available in the summer season only. Mango can grow well in large containers and a greenhouse as well. Mango trees are shady in nature. They grow very fast and can reach a height of as much as 65 ft. The life of mango trees is generally very long and some specimens are known to be over 300 years old and still fruiting. More than 492 species of insects, 17 species of mites and 26 species of nematodes have been reported to be infesting mango trees, about 45 per cent of which have been reported from India. Almost a dozen of them have been found damaging the crop to a considerable extent causing severe losses and, therefore, may be termed as major pests of mango. These are hopper, mealy bug, inflorescence midge, fruitfly, scale insect, shoot borer, leaf webber and stone weevil. Of these, insects infesting the crop during flowering and fruiting periods cause more severe damage. The insects other than those indicated above are considered as less injurious to mango crop and are placed in the category of minor pests.

Major pests of Mango:

Amritodus atkinsoni Idioscopus niveosparsus Idioscopus clypealis

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Batocera rufomaculata Indarbela tetraonis Indarbela quadrinotata Chlumatia transversa

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Borers 1 Mango Stem Borer 2 Mango Bark Borer / Mango Bark Eating caterpillar 3 Mango Shoot Borer Inflorescence & fruit feeders 1 Mango Hoppers


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Mango Inflorescence Midge

3 Mango Aphid 4 Mango Flower Webber 5 Mango Loopers 6 Mango Bud Mite 7 Mango Fruit Fly 8 Mango Nut Weevil 9 Tea mosquito bug 10 Inflorescene midge Leaf Feeders 1 Mango Shoot Webber 2 Mango Leaf Gall Midge 3 Mango Leaf Twisting Weevil 4 Mango Hairy Caterpillars 5 Red tree ant Sap Feeders 1 Mango Hoppers

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Mango Scales

Erosomyia indica Dasineura amaramanjarae Toxoptera odinae Eublemma versicolor Thalassodes quadraria Aceria mangiferae Bactrocera (Dacus) dorsalis Sternochetus mangiferae Helopeltis antonii Erosomyia indica Orthaga exvinacea Procontarinia matteiana Apoderus notatus Euproctis fraternal, E. similis Prothesis scintillans Oecophylla smaragdina Idioscopus niveosparsus Idioscopus clypealis Amritodus atkinsoni Aspidiotus destructor Pulvinaria polygonata Drosicha mangiferae Oecophyla smaragdina Paratetranychus mangiferus

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1. MANGO HOPPERS (Maamidi Tena Manchu Purugu) Amritodus atkinsoni (largest) Cicadellidae: Homoptera Idioscopus clypealis (Smallest) Cicadellidae: Homoptera Idioscopus niveosparsus (Medium) Cicadellidae: Homoptera • Of all the mango pests, mango hoppers are considered as the most serious and widespread pest throughout the country. • They occur as regular pests. • They are specific pests (i.e., monophagous) of mango. • Hoppers are endowed with a small sized vedge shaped body. • They move diagonally. • The pest causes severe inflorescence losses. • Among all three species, third one (Idioscopus niveosparsus) causes maximum damage in Mango. • Idioscopus atkinsoni is commonly met with in Bengal, Bihar, Gujarat, Maharashtra, the Punjab, Uttar Pradesh and Orissa. • Idioscopus clypealis occurs in Bengal, Bihar, Madras, Uttar Pradesh, Maharashtra, Mysore and the Punjab. • Idioscopus niveosparsus is found in Uttar Pradesh, Bengal, Gujarat, Madras and Maharashtra.

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3 Mango Giant Mealy Bug 4 Mango Red Ant 5 Mango Red Spider Mite Other insects pests 1 Termites Odontotermis obesus ** Highlighed pests are major and important for India.


Amritodus atkinsoni (Idioscopus atkinsoni) (Idiocerus atkinsoni) Largest Light Brown in Colour Two spots on scutellum

Idioscopus clypealus (Idiocerus clypealus)

Idioscopus niveosparsus (Idiocerus niveosparsus)

Smallest Light Brown in Colour Two spots on scutellum, and a dark spot on vertex

Medium sized Three spots on scutellum, prominent white band across wings

The nymphs of Idiocerus clypealis are dull yellow or dust yellow, whereas those of Amritodus atkinsoni are pale yellow, elongated and more active. Nature & Symptoms of damage: • The pest is prevalent during flowering season. • Hoppers are present round the year in the orchard but population used to be high during February to April and June to August. • During the emergence of inflorescence, the pest multiplies in large numbers. • During the remaining part of the year, they occur in small numbers inside barks or leaves of mango. • Both nymphs and adults suck the sap from the tender leaves, which results in withering and shedding of flower buds and flowers. • Large number of nymphs and adult insects puncture and suck the sap of tender parts, thereby reducing the vigour of the plants.

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Heavy puncturing and continuous draining of the sap causes curling and drying of the infested tissue. They also damage the crop by secreting a sweet sticky substance which facilitates the development of the fungus Maliola managiferae, Capnodium spp. commonly known as sooty mould affecting adversely the photosynthetic activities of the leaves. The honey dew on upper surface of leaves and flower shoots become black and fruit set is stopped. The heavy infestation results in reduction in flowering, fruit setting, pre-mature fruit fall, and yields. Revised during 2011

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Hopper population shoots up in February-April and June-August. In AP this symptom is popularly called as `Tena Manchu Purugu' Due to recurrent annual damage by the hoppers, some orchards fail altogether to blossom. • Egg laying also inflicts injury to the inflorescence. • The growth of young trees is much retarded and older trees do not bear much fruit. • Damage to the mango crop may be as high as 60 per cent. Biology • After spending adult stage in winter, Adult female lays about 200 eggs singly during February-March, by penetrating them into the midrib of the young leaves, shoots, flower stalks and unopened flowers. Eggs are dull white in colour initially which later turn into light brown. They are oval in shape with pointed and blunt ends. Incubation period vary from 4 to 8 days. • After hatching, the nymphs are pinkish in colour which later turn into pale brown with prominent red bulged eyes along with long black coloured bristles on abdomen. Nymphal period is 10-14 days. Female can be identified with the sickle shaped ovipositor. • The nymphs mature during June to October (feed and breeds on the vegetative shoots) and January to March (breeds on flowers and inflorescence). Adult longevity 3-4 days. • The nymphs and adult population increase to record proportions during February-April and June-August periods. These are two peak generations a year out of several generations. The June-August generation hoppers are seen on mango tree trunks while February-April hoppers generation is confined to the foliage and causes severe loss. • Adult hopers spend winter in the cracks in the barks of the tree. • Hoppers love shady and damp places, particularly at noon. Management • Avoiding water logged or damp condition in the garden • Avoid close planting / high density planting, as it provides favourable habitat for hopper multiplication. • Remove over crowded, criss-cross, overlapping, infested and infected branches to discourage the microenvironment for hopper multiplication. • Clean cultivation-Orchards may be kept clean by ploughing and removal of weeds • Adopt resistant varieties and avoid susceptible varieties. Resistant: Baneshan, Chinnarasam, Bangalora, Khadar Moderately Resistant: Gaddemar, Rumani Susceptible: Himayuddin Highly susceptible: Padiri, Neelam, Mulgoa, Peter and Sindura • Spray carbaryl 50 WP @ 4g/lt or malathion 50 EC @ 2 ml/lit or endosulfan 35EC @ 2ml/lit at the panicle emergence (February) and when the fruits are at marble stage (March). If necessary the spraying may be repeated. • Spraying methyl parathion (0.025%), monocrotophos (0.025%), fenitrothion (0.25%) with high volume sprayer @ 10 L/tree significantly reduce hopper population. • In recent years, new molecules such as imidacloprid 17.8 SL at 0.5 ml/lit or thiamethoxam 25 WG at 0.25 g/lit or Lamda-cyhalothrin 5 per cent EC at 0.5 ml/lit were found to be highly effective and economical. • Spraying Beauveria bassiana @ 108 cfu/ml during cooler periods. • For better results the spray application should coincide during the active stage of the pest and hence careful hopper monitoring from the month of December is essential.

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Neem based spraying of insecticides if required. Spray neem oil 3% or Neem seed kernel powder extract 5 per cent. The spraying should be done first to stem, then branches, twigs, leaves and inflorescence for effective control.

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Eggs are laid singly either in the slits/cracks of tree trunk or in the cavities in main branches and stems covered with a viscous fluid. Eggs hatch in 1-2 weeks. The developing grub bores inside the stem and grows to about 100 x 20 mm and fleshy in about 6 months. Grubs are cream coloured with dark brown head. Grub pupates inside the larval tunnel in the stem itself, during July. Pupal period lasts for 4-6 months. Beetle emerges in July-August. There is only one generation of the pest in a year. The affected portions should be removed and destroyed. The bore holes may be traced and opened. In case of trunks, insert swab of cotton wool soaked in chloroform, or petrol or carbon bisulphide or kerosene oil, into the holes and seal the same with mud or placing some crystals of Para dichloro benzene and then closing the hole with wet mud. When burrows are superficial, extract the grubs with stiff hooked wire and paint bordereaux pastes. Remove the webs from tree trunks and put emulsion of Monocrotophos (0.05%) or DDVP (0.05%) in each hole and plug them with mud. Revised during 2011

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2. MANGO STEM BORER (Kaandam Toluchu Purugu) Batocera rufomaculata Cerambycidae: Coleoptera • Stem Borer (Batocera rufomaculata) is widely distributed in India and attack a number of fruit trees including mango. • Mango stem borer is common pest in India. • It is a polyphagous pest, besides mango, it attacks apple, fig, mulberry etc. • Damage is caused by the grub of this beetle as it feeds inside the stems boring upward resulting in drying of branches and in severe cases attained stem also dies. • Masses of refuse and sap exude from the bored hole. • Leaves of damaged branches also fall. • Branches collapse in severe cases. • Adult beetles, 35-50 mm in size, are stout, conspicuously long, and greyish brown in colour with dark brown and black spots. It has two pink dots and lateral spines on thorax and has hard elytra and long horned. • The grub is also conspicuous when full grown, the grub is yellowish white, freshly and measures about 100 mm long with dark brown head and having strong jaws.


3. MANGO NUT WEEVIL / MANGO STONE WEEVIL (Maamidi Tenke Purugu) Sternochetus mangiferae Curculionidae: Coleoptera (Cryptorrhynchus mangiferae) • This insect is widely distributed in tropics. • Sternochetus frigidus, of the pest is found in Assam and Bengal. • Cryptorrhynchus gravis occurs in eastern Bengal and Assam. • Sternochetus mangiferae in South India and Orissa. • All species breed in the stone. • They have not so far been reported to attack any other fruit. • Sweeter varieties such as Alphonso, Bangalora, Neelum, etc. are more prone to attack by this pest. • The pest is most sensitive to temperature and low humidity as well. It is more confined to humid areas. Some times even 100 per cent fruits are infested. • Due to this Maryland of the USA does not allow mango imports from India. • The adult weevil is about 6-8 mm in length (short) grayish brown in colour and stoutly built. Antennae 10 segmented and elytra convex.

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In non-fruiting season, beetle remains hidden under the bark during the night times. The female adult lays minute, white eggs on the surface of tender mango fruits. The mother weevil selects a place on the fruit, makes shallow depression in a boat shape by scooping and then lays a single egg and covers with a transparent liquid secretion. This result a crescent shaped deep cut near the posterior end of egg. The liquid flows from the fruit and also covers the egg and dries up. One weevil lays about 15 eggs, and egg hatches within a week. The grub as soon as it hatches out from egg, tunnels in a zigzag manner through pulp, endocarp and seed coat. Finally it reaches the cotyledons. As the fruit develops, the tunnel gets healed up. The grub feeds on the cotyledons and destroys them. Pulp is discolored around the affected portion. Larval period lasts for 5 weeks. Pupation takes place inside the seed. Pupal period lasts for 7 days. In the mean time, the injury that was done while boring into the nut portion gets nicely healed up. During the life cycle of the weevil, if the infested mango fruit falls and decays, then adult comes out by cutting the stone. If not, adult makes its way to come out through pulp etc. The adult emerges also feeds on developing seed. This hastens the maturity of infested fruit. Adults hibernate until the next fruiting season. There is only one generation in a year. Life cycle is completed in 40-50 days only one generation in a year.

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Management • Important critical stages for management: Diapausing adults on tree trunk during September-October, and newly emerged larvae seen on developing fruit at six weeks after fruit set (easy to control the pest.) • Proper disposal of the stones and fallen mangoes should be done. • General cleanliness and destruction of the weevils on the bark during August should be undertaken. • The infested bark should be washed with kerosene emulsion. • The pest population can be kept under check by destroying the affected fruits and exposing the hibernating weevils by digging the soil. • Drenching spray of either Carbaryl @0.2% (4 g/l of water) or Quinalphos @0.5% (2 ml/l of water) in Sept-Oct on the tree trunk up to a height of 4m. • Deltamethrin spray @0.002% (1 ml/l of water) after six weeks of fruit set. • Spraying the trees with Fenthion (0.01%) is found effective. • In Alphonso and Banganapalli, a single spray of Monocrotophos 36 EC 1.5ml/litre of water at marble stage gave 100% and 97.5% control of stone weevil respectively. • In Totapuri, Carbaryl 50 % WDP @ 4 g/ litre is effective in controlling stone weevil. • Hot water treatment of fruit for specified period (n\hot water at 60°C) kills the weevil inside the stone, but not fruit fly maggot which is within the pulp. • Dipping hard fruits in EDBC at 50% for 2 hours.

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4. MANGO FRUIT FLY / ORIENTAL FRUIT FLY (Pandu Eeega) Bactrocera dorsalis Trypetidae: Diptera (Chaetodacus ferrugineus, Chaetodacus dorsalis, Dacus dorsalis) • Bactrocera dorsalis forms part of a species complex, within which over 50 species have been described in Asia. • Many earlier records of B. dorsalis from southern India, Indonesia, Malaysia, Philippines and Sri Lanka are based on misidentifications of what are now known to be other species. • Seven of these species are also recognized to be pests of cultivated plants. • Because most of these have only recently been described, their status as quarantine pests for Europe remains to be fully assessed. • Bactrocera dorsalis is a serious pest of a wide variety of unrelated fruit crops, but seldom cucurbits. • It was recognized as one of the five most important pests of agriculture in South East Asia. • The oriental fruit fly is one of the most serious pests of mango in the country, which has created problem in the export of fresh fruits. • Five species occur in India. Their distribution and host range are given below.


Dacus correctus Bezzi Dacus diversus Coqu.

Dacus hageni de Meijeri

Distribution Widely distributed

Peach, mango, Uttar Pradesh, the Punjab, guava, bael, fig, Bihar, Madhya Pradesh, sapota, tomato, Maharashtra, Madras, Zizyphus, toria, Mysore custard-apple, brinjal, melon Citrus, Zizyphus, Bihar, Madras, the beal, peach, mango Punjab, Madhya Pradesh Guava, citrus, Madras, Mysore, banana, Eugenia, Maharashtra the Punjab, mango West Bengal, Uttar Pradesh, Assam

Mango, sapota, pummelo, pumpkin, gourd, tomato

Assam, Sikkim, Bihar, Uttar Pradesh, Madhya Pradesh, the Punjab, Madras, Mysore

Host range: • Bactrocera (Dacus) dorsalis occurs on a wide range of fruit crops, for example in China and Japan on Annona squamosa, apples, bananas, Capsicum, Clausena lansium, guavas, mangoes, oranges, peaches, plums and tomatoes. • The oriental fruit fly (Bactrocera dorsalis) attacks over 300 cultivated and wild fruits including Annona, avocado, banana, bittermelon, citrus, coffee, guava, mango, papaya, passion fruit, peppers, and tomato. This pest will apparently breed in all fleshy fruits. • It does not attack cucurbit crops such as cucumber and squash. • Due to confusion between Bactrocera dorsalis and related species in South East Asia, some published host data may concern other species within the Bactrocera dorsalis species complex. Distribution: • Bactrocea dorsalis as now described occurs in the northern part of the range of the dorsalis complex in Asia. The other species occur in the south of the Indian subcontinent and in South East Asia. • Asia: Bangladesh, Bhutan, Cambodia, China, Hong Kong, India (Assam, Bihar, Delhi, Haryana, Jammu and Kashmir, Karnataka, Maharashtra, Manipur, Orissa, Punjab, Rajasthan, Sikkim, Tamil Nadu, Uttar Pradesh, West Bengal), Japan, Myanmar, Nepal, Pakistan, Sri Lanka, Taiwan, Thailand (northern), United Arab Emirates, Viet Nam. • North America: Outbreaks in USA (California, Florida), eradicated (FAO, 1987) but found again in California in 1989. Reported in Hawaii since about 1945. • EU: Absent. • EPPO region: Absent Revised during 2011

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Dacus zonatus Saunders

Host range Mango, guava, loquat, peach, apple, fig, quince, banana, plum, pomegranate, citrus, apricot, and a variety of vegetables.

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Pest Dacus dorsalis Hendel Mango fruit fly, Oriental fruit fly.


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Nature & symptoms of damage: • The damage to crops caused by fruit flies result from 1) Oviposition in fruit and soft tissues of vegetative parts of hosts 2) Feeding by the larvae, and 3) Decomposition of plant tissue by invading secondary microorganisms. • They cause dark punctures in the fruits for oviposition from June to August. • Larval feeding damage in fruits is the most damaging. Mature attacked fruits develop a water soaked appearance. • Young fruits become distorted and usually drop. • The larval tunnels provide entry points for bacteria & fungi that cause the fruit to rot. • These maggots also attack young seedlings, succulent tap roots of watermelon, and stems and buds of host plants such as cucumber, squash and others. • Later, a brownish rotten patch makes its appearance on the surface of the attacked mango fruits with the characteristic oozing of fluid after the maggots have eaten the pulp. • The fruit eventually drops when the maggots come out and enter the soil for pupation. • A very high percentage of ripe mangoes in important mango-growing areas are rendered unfit for consumption by the maggots of these fruit flies. • In comparison, oriental fruit flies are considered as primary pests and Mediterranean fruit flies are rare pests in typical situations. Although the actual injury by fruit flies is relatively low, these flies are considered a major pest of many crops in terms of exporting. It is therefore necessary to treat the fruits with post-harvest quarantine treatments. • The economic importance of the fruit fly cannot be evaluated entirely from the standpoint of the direct damage to the various crops affected. Quarantine laws aimed at preventing the entry and establishment of fruit flies in areas where it does not occur often reduces the export potential of locally grown crops. Biology: • Adult flies emerge from pupae during morning hours and mate at dusk. After 14 days, they lay eggs. • Female inserts eggs by sharp ovipositor, preferably in soft fruits. The female first make a cavity by sharp ovipositor and inserts slender, white color eggs, under the skin of the fruit, in clusters of 5-30, during evening hours. During egg laying, female release a gummy substance which covers and cements and makes eggs water proof. Female lays 58-95 eggs in 14-54 days. They hatch in 2 to 7 days.

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Marks of identification of Bactrocera dorsalis • Adult: Fly is reddish brown in color, face with a dark spot, lemon yellow markings (striped bodies) in thorax with spotted wings. Active throughout year. They have relatively large red eyes. • Maggots: leg less, head less, dirty white, thicker at one end and tapering at the other to a point. Wriggling creatures.


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The white larva is legless, and resembles an elongated cone. The mouth is at the pointed end of the body. There are 3 larval stages, or instars. The third instar is about 2/5 inch long. The entire larval stage lasts for 11-15 days. Maggots bore into pulp, forming galls. Fruits decay due to secondary bacterial infection. Larval period 3 days in summer and about three weeks in winter. Mature maggots come out and jump to ground and select suitable place, enter the soil and pupate. The puparium is yellowish-brown, seed-like and barrel shaped. Adults emerge in about 10 days.

Management: • Collection and disposal of the fallen infested fruits. • Under-sized fruits left on the tree should be picked and destroyed. • Ploughing the orchards and exposing the diapausing pupae to sun’s heat. • If the trees are few, bagging the fruits with cloth or paper bags can be tried for protection. • For the destruction of adult flies congregating in the night under the leaves of fruit trees, application of a suitable spray, viz., dilution of eight times of diesel-oil emulsion (diesel oil 4.5 litres, soft soap 0.45 kg. and water 4.5 litres) is recommended. • Heavy application of dust and sprays of pyrethrum or BHC on the tree reduces the number of adult flies. • Citronella oil, liquid ammonium carbonate, ammonium sulphate, molasses and the mixtures including some fruit juices are utilized in other countries as attractants with partial success. • D.dorsalis is attracted by citronella, liquid ammonia, clense, methyl-eugenol, bay-oil, vanilla, and pollard mixture. • The adult fruit flies can be controlled by bait sprays of carbaryl (0.2%) + protein hydrolysate (0.1%) or molasses starting at pre-oviposition stage (first week of April), repeated once after 21 days. • Another method to control these flies is to hang traps containing a 100 ml water emulsion of methyl euginol (0.1%) + Malathion (0.1%) during fruiting (April to June). About 10 such traps are sufficient for one hectare of orchard. • The bait should be freshly prepared before spray. • Early harvesting of mature fruits. • The spread of these destructive pests can be prevented only by applying strict quarantine measures. • As per the experiments conducted in IIHR, Bangalore against fruit fly, hot water treatment at 480C for one hour or Vapour Heat Treatment (VHT) of fruits before storage and ripening (for killing the larvae) gave total control in Alphonso and Totapuri. Revised during 2011

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The emergence of fruit fly starts from April onwards and the maximum population is recorded during May-July, which coincides with fruit maturity. The population declines slowly from August to September after that it is non-existent up to March.

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5. MANGO SHOOT BORER (Maamidi Komma Toluchu Purugu) Chlumetia transversa Noctuidae: Lepidoptera • Shoot Borer (Chlumetia transversa) is a serious pest of mango (especially seedlings and young trees) that eats developing leaves and tunnels into the midrib and terminal shoots. • This pest is found all over the country. • Larvae bore into the young shoot resulting in dropping of leaves and wilting of shoots. Larvae also bore into the inflorescence stalk. • The adult moths are stout, shining grey in colour and measure about 17.5 mm with expanded wings. Hind wings are light in colour.

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6. MANGO MEALY BUGS (Maamidi Pindi Purugu) Drosicha mangifeare Psuedococcidae: Homoptera • The mango mealy bug (Drosicha mangiferae Green) is responsible for devastating the crop during its serious incidence. • It is not as widespread as the mango hopper. • It is easy to recognize by its large flattish and plump females, which are covered with a white meal. Revised during 2011

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Female moths lay eggs on tender leaves. After hatching, young larvae enter the midrib of leaves and then enter into young shoots through the growing points by tunnelling downwards. The full grown larva is dark pink in colour with dirty spots and measures about 22 mm in length. There are four overlapping generations of the pest in a year and it overwinters in pupal stage. The attacked shoots may be clipped off and destroyed. Spraying of Carbaryl (0.2%) or Quinalphos (0.05%) or Monocrotophos (0.04%) at fortnightly intervals from the commencement of new flush gives effective control of the pest. A total of 2-3 sprays may be done depending on the intensity of infestation.

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Management • Flooding of orchards with water in the month of October kills the eggs. • Ploughing the orchards in the month of November exposes the eggs to sun’s heat. • Partial check can be affected by cleaning the debris and soil at the base of the trees and also through the cultivation of the soil under the trees after the monsoon. • In the middle of December, 400 gauge polythene sheet of 25 cm width may be fastened to the tree trunk. Polythene (400 gauge) bands of 25 cm width fastened around the tree trunk have been found effective barrier to stop the ascent of nymphs to the trees. The band should be fastened well in advance before the hatching of eggs, i.e., around November - December. • Rake up the soil around the tree trunk and mix with 2% Methyl Parathion dust. Revised during 2011

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It is another major pest of mango in India and is widely distributed all along the Indogangetic plain. Drosicha mangiferae Green is the most common mealy bug and causes severe damage to mango crop throughout the country. Nymphs and adults suck the plant sap and reduce the vigour of the plant. Excessive and continuous draining of plant sap causes wilting and finally drying of infested tissue. They also secrete honey dew, a sticky substance, which encourages the development of a fungus Maliola mangiferae, termed as sooty mould. The adult male is winged and small, female is bigger and wingless. The female, after copulation, crawl down the tree in the month of April-May and enter in the cracks in the soil (at a depth of 5-15cm) for laying eggs in large numbers encased in white egg sacs. The eggs lie in diapause state in the soil till the return of the favourable conditions in the month of November-December. The nymphs emerge in DecemberJanuary, just after hatching, the minute newly hatched pink to brown coloured nymphs crawl up the tree and start climbing up the tree where they congregate together and suck juice from young shoots, panicles and flower pedicels. The affected parts dry up and yield is reduced substantially. The females can be identified by their flat shape, covered with white mealy powder. Once the pest manages to reach the top of the plant; its control becomes rather difficult. They are considered more important because they infest the crop during the flowering season and if the control measures are not taken timely, the crop may be destroyed completely.

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The dust may also be sprinkled below the polythene band on the tree. The congregated nymphs below the band may be killed by any of the suggested insecticides. The common method of control is to prevent the ascent of the nymphs up the trees by fastening a grease band on the trunks a few feet above the ground. The band may be made by applying a mixture of rosin and castor oil (4:5) or ostico on a strip of paper, 7.5 cm. to 10 cm. in width. The lower end of the paper should be flushed with the tree by applying mud, etc. The rosin-castor-oil band loses its stickiness in eight to ten days, when it should be renewed by applying fresh material. Chemical control by using a mixture of 0.15 per cent nicotine sulphate, 1.25 per cent sesame oil, 0.25 per cent soft soap, 0.3 per cent washing soda in water and 0.3 per cent ethyl alcohol is effective. Application of 250 g per tree of Methyl Parathion dust 2 per cent or Aldrin dust 10 per cent in the soil around the trunk kills the newly hatched nymphs which come in contact with the chemical. In case the nymphs climbed up the tree, they should be controlled at the earliest by spraying carbaryl (0.2%) or nuvacron (0.04%). In case of potted plants in nursery, fumigation of the plants with HCN gas has been done successfully. No parasite or predator has been found so far to control the mealy bugs on an extensive scale. Menochilus sexmaculatus, Rodolia fumida and Sumnius renardi are important predators in controlling the nymphs. The entomogenous fungus Beauveria bassiana is found to be an effective bioagent in controlling the nymphs of the mealy bug. The above IPM schedule holds promise to control the mealy bug but spraying of neem product and the spores of the fungus Beauveria bassiana will further ensure the reduction of the pest population.

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7. MANGO LEAF WEBBER (Maamidi Aaku Mudatha) Orthaga exvinacea Pyralidae: Lepidoptera • Commonly found throughout the plains of South India. • The pest is attaining serious proportions. • Its infestation starts from the month of April and goes up to December. • The adult moths are medium sized and sombre coloured. • Eggs are laid singly or in clusters within silken webbings on leaves. • Upon hatching, the caterpillars feed on leaf surface by scrapping. Later, they make web of tender shoots and leaves together and feed within. Generally, 1-9 larvae are found in a single web. Fully grown caterpillar measures 2.5 to 3 cm. They are brownish in colour with brown spots and whitish striation on the dorsal surface.


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8. MANGO SCALES (Maamidi Polusu Purugu) Aspidiotus destructor Pulvinaria polygonata • Several species of scale insects attack the mango in India. • Of these five are most serious: Aspidiotus destructor, Pulvinaria polygonata, Parlatoria pergandii, P.cinerea and Lepidosaphes gloverii. • A.destructor occurs in the mango-growing tracts of Uttar Pradesh and the Punjab; Parlatoria cinerea and Pulvinaria polygonata in Uttar Pradesh, and Parlatoria mangiferae in Orissa. A.dectyospermi Morgan, Diaspis mangiferae Green, and Lecanium bicruciatum Green occur in S. India. L.gloverii occurs in Uttar Pradesh only. • Scale insects were not considered serious pest on mango in any part of the country till recently, but of late, they have assumed the status of serious pest in certain parts of the country. • These scale insects are generally found on mango trees but the other host plants are citrus, palms, banana, sugarcane, etc • The nymphs and adult scales suck the sap of the leaves and other tender parts and reduce the vigour of the plants. They also secrete honeydew which encourages the development of sooty mould on leaves and other tender parts of the mango plant. In case of severe scale infestation, growth and fruit bearing capacity of the tree is affected Revised during 2011

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Pupation takes place inside the webs in silken cocoons. However, the last generation (December-January) pupates in the soil. The pupae diapause for about five to six months. The infestation is severe in shady conditions. Old orchards with lesser space between tree canopies have more infestation than open orchards. Leaves are skeletonised or leaves wither and drop away. Dry top shoots are conspicuous and flower stalk formation is affected. Pruning of infested shoots & burning in the month of April to July is found effective. Raking of the soil around the base of the trees in January, after the last generation has pupated, helps in checking the pest population. Three sprays starting from the last week of July at 15 days interval with Carbaryl (0.2%) or Monocrotophos (0.05%) or Quinalphos (0.05%) effectively controls pest.

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9. INFLORESCENCE MIDGE Erosomyia indica (Cecidomyiidae: Diptera) • The mango inflorescence midge, Erosomyia indica is another major pest of mango. • Recently, this pest has become very serious in certain pockets of Uttar Pradesh causing serious damage to mango crop by attacking both the inflorescence and the small fruits. • The adult midge is harmless minute flies which are short lived and dies within 24 hours of emergence after copulation and oviposition. The flies lay eggs singly on floral parts like tender inflorescence axis, newly set fruit or tender leaves encircling the inflorescence. The eggs hatch within 2-3 days. • Upon hatching, the minute maggots penetrate the tender parts on which the eggs have been laid and feed on them. The floral parts finally dry up and are shed. The larval period varies from 7-10 days. The mature larvae drop down into the soil for pupation. • The pupal period varies from 5-7 days. • There are 3-4 overlapping generations of the pest spread over the period from JanuaryMarch. • Thereafter, as the weather conditions turn unfavourable, the mature larvae undergo diapause in the soil instead of pupating. They break diapause on the arrival of favourable conditions in following January. • The midge infests and damages the crop in three different stages. The first attack is at the floral bud burst stage. The eggs are laid on newly emerging inflorescence; the larvae tunnel the axis and thus destroy the inflorescence completely. The mature larvae make small exit holes in the axis of the inflorescence and slip down into the soil for pupation. The second attack of the midge takes place at fruit set. The eggs are laid on the newly set fruits and the young maggots bore into these tender fruits, which slowly turn yellow and finally drop. The third attack is on tender new leaves encircling the inflorescence. The most damaging one is the first attack in which the entire inflorescence is destroyed even before flowering and fruiting. The inflorescence shows stunted growth and its axis bends at the entrance point of the larvae. It finally dries up before flowering and fruit setting. Revised during 2011

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adversely. Among the above scale insects, P. polygonata is posing a serious threat to mango industry of western UP. The damage starts with the advent of summer. Pruning of infested branches and burning them can be resorted to for the control of small scale infestation. Sprays dimethoate (0.06%) or phosphomidon (0.05%), monocrotophos (0.04%) at an interval of 20 days are effective.


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10. BARK EATING CATERPILLARS Inderbela quadrinotata Inderbela tetraonis • This pest is found damaging a variety of plants including a number of fruit trees, forest trees and ornamentals all over India. • The old, shady and neglected orchards are more prone to attack by this pest. • Fruit trees are damaged to a considerable extent by the bark-eating caterpillars, which attack trees of all ages, particularly the older ones, lowering their vitality. • When severely infested, the entire branch or tree may die. • Three species of this pest have been recorded in India, viz., Inderbela quadrinotata Wlk., I.tetraonis M.o. and I.dea Swinhoe. I.quadrinotata is found in Uttar Pradesh, Maharashtra and Madhya Pradesh. a number of host plants are known, viz., mango, guava, Zizphus, litchi, orange, pomegranate, kachnar, loquat, mulberry, and Eugenia. • Larvae of this moth feed on the bark and weaken the tree. The attack by this pest is characterized by the presence of long-winding, thick, blackish or brownish ribbon-like masses composed of small chips of wood and excreta, both of which intermix with the help of adhesive material secreted by the caterpillar, which bores into the bark of the trees and remains in the tunnels dug into the sap-conducting tissues. By continuously devouring the tissues, it tunnels through the stem and branches. This injury weakens the stem, resulting in drying of the branches and finally of the tree itself. • The moth is light grey in colour with dark brown dots and measures about 35-40 mm with expanded wings. • A single female lays about 300-400 eggs in batches on the bark. • The full grown caterpillar is dirty brown in colour and is about 35-45 mm in length. • The caterpillar spins brown silken web on the tree which consists of their excreta and wood particles. • Larvae also make shelter tunnels inside the stem in which they rest. Larvae actually feed from April to December. • There is only one generation in a year. • The caterpillars can be killed by inserting an iron spike into the tunnels. • This insect has also been successfully controlled by injecting ethylene glycol and kerosene oil in the ratio of 1:3 into the tunnel by means of a syringe and then sealing the opening of the tunnel with mud. • The caterpillars are killed inside the tunnel by poison vapors liberated by the mixture of ethylene glycol and kerosene. • Another method of control is dipping a small piece of cotton in any of the fumigants, like carbon bisulphide, chlorosal or even petrol, and introducing it into the tunnel and sealing the opening with clay or mud. • A mixture of equal parts of creosote and chloroform or petrol or cheap kerosene oil may be injected into shelter tunnels to kill the active boring caterpillars. • As a preventive measure, spraying of the attacked trunk and branches with 0.25 per cent DDT emulsion or 0.1 per cent parathion emulsion should be done. Revised during 2011

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As the larvae pupate in the soil, ploughing of the orchards expose pupating as well as diapausing larvae to sun’s heat which kills them. Soil application of Methyl Parathion also kills pupating as well as diapausing larvae in the soil. The insecticide in the soil should be applied after monitoring larval population on white sheet below the tree. Spraying of 0.05% Fenetrothion or 0.045% Dimethoate at the bud burst stage of the inflorescence has been found effective in controlling the pest population.

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11. SHOOT GALL PSYLLA Apsylla cistellata Psyllidae: Homoptera • It is a very serious pest of mango in many parts of India, particularly in Terai region of U.P., north Bihar and West Bengal. This pest occurs throughout northern India. No other host plant has so far been recorded. • Mango shoot-gall-maker, Apsylla cistellata Buckton, attacks the growing buds of the shoots with the result that green cone-shaped galls in the leaf axil are formed. • This pest creates green conical galls in leaf axis. • The activity of the pest starts from August. • The galls dry out after emergence of psyllid adults in March. • The females lay (approx. 150 eggs) white eggs in the midribs as well as in lateral axis of new leaves, during March-April. • Nymphs are flat and pale yellow in colour, emerge from eggs during AugustSeptember and crawl to the adjacent buds to suck cell sap. • As a result of feeding, the buds develop into hard conical green galls. • The galls are usually seen during September-October. Consequently, there is no fruit set. • They prevent the development of leaf flushes or inflorescences. These shoots gradually die resulting in a heavy loss of yield. • The galls with nymphs inside should be collected and destroyed to prevent carryover of the pest. • The pest can effectively be controlled by spraying Monocrotophos (0.05%) or Dimethoate (0.06%) or Quinalphos (0.05 %) at 2 week intervals starting from the middle of August. • The use of same chemical for every spray should be avoided.

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13. TEA MOSQUITO BUG Helopeltis antonii Miridae: Hemiptera • Major pest of cashew, occasionally damages mango and other fruit crops. • Found in Kerala, Karnataka, Goa, Maharashtra, Tamil Nadu and Andhra Pradesh. • Adult is a reddish-brown bug with black head, red thorax, and black and white abdomen. A knobbed process arises mid-dorsally on thorax. • Eggs are inserted into epidermis of tender shoots and axis of inflorescence. • Adults and nymphs feed on petioles, tender shoots and leaf veins causing necrotic lesions. • Drying of shoots, inflorescence and dropping of the flowers and young fruits is seen. • If infestation is severe, spray insecticides like endosulfan or carbaryl.

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12. RED TREE ANT Oecophylla smaragdina Formicidae:Hymenoptera • The ants web and stitch together a few leaves, usually at the top of the branches and build their nests. • The ants are carnivorous and prey upon small insects. • However, indirect damage is caused by protecting insects like aphids and scales, which excrete honeydew. • Besides, being ferocious may also be of nuisance to workers around. • Reme nests and their destruction. • Dust with BHC 10% dust or Heptachlor 5% dust or spraying with BHC 50% WP at 0.16% during off season in required quantities.


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15. MITES Paratetranychus manguferus • Among non-insect pests, mites are of importance. • They cause damage not only to growing trees but also at seedling stage. • Three species, Paratetranychus mangiferus, P.yothersi and Eriophyes sp., are involved. • Mites, as a mango pest, have been observed in all the mango-growing tracts of India. • Eugenia, grapevine, and avocado are some of its alternate hosts. • P.mangiferus infests only the upper surface of the mango leaves. • The mites spin a profuse webbing and cause mottling of the leaves owing to the disappearance of colour at the spots punctured in feeding. • Several species of predatory mites, coccinellids and thrips prey upon these mites. • For a limited number of trees, removal and destruction of infested parts of plants should be resorted to. • Spraying the affected plants with lime-sulphur wash (1:2:10) or 0.05 per cent parathion or diazinon has proved effective. • Sulphur, in whatever form it is used, is effective in controlling mites.

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14. TERMITES Odontotermis obesus Termitidae: Isoptera • Termites are not the primary agents responsible for any damage to the mango trees, to which they find access generally when trees are in a weakened condition due to some other cause. • Several species have been reported in India but out of these eight are common, viz., Odontotermes obsesus Ramb. Microtermes obesi Hilmgr., O.assuthi Hilmgr., O.feae Wasmann., Trinervitermes beimi Wasmann., Coptotermes reimi Wasmann., Heterotermes indicola Wasmann., and Nevbevares gardneri Synder. • These species occur in almost all the states of India. • The principle food of the termites is fibrous material (cellulose). Termites mostly prefer dead wood and bark of the trees. They generally attack the fruit trees like mango, cashew sapota etc., even though there are no clear symptoms exhibited by the trees, but there will be a considerable reduction in yields. • The worker termites feed on roots, shoots and trunks of the mango tree, which sometimes dries up if the roots are severely damaged. • The earthen galleries form a safe passage on the trunk and branches of the trees for the termites, which go on destroying the bark and tissues within these galleries. • For the control of termites, dusting with 5% BHC in soil around the infested plants, and raking in into the soil has proved effective. • The trunk and branches affected by termites may be dusted with 5% BHC dust after scraping the termite galleries. • Orchards should be kept clean and free of all refuse vegetation. • All the dead and decaying wood, whether on the trees or in the ground, should be regularly removed. • In areas liable to termite infestation, pits prepared for planting should first be treated with crude-oil emulsion, about one-fourth kilogramme of which should be thoroughly mixed with four average-sized baskets of soil. • Application of tar to the trunks of the tree 1-1½ mts length from the surface of the soil. • Removal and destruction of termite mounds.


Lecture 30: (INSECT PESTS OF CITRUS) 30. Major insect pests of citrus-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of butterfly, fruit sucking moth, citrus leaf miner, psylla and rust mite; Minor insect pests of citrus-nature and symptoms of damage and management practices of bark eating caterpillar, blackfly and leaf mite.

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Adult is a big beautiful butterfly with • yellow and black markings on all the four wings. Its hind wings have a brick red oval patch near the anal margin and a tail like • extension behind. Unlike most swallowtails, it does not have prominent tail. It is perhaps the most widely distributed swallowtail in the world. As the butterfly ages, the yellow markings on the wings deepen to orange.

The Common Mormon (Papilio polytes) is a common species of swallowtail butterfly widely distributed across Asia. This butterfly is known for the mimicry displayed by the numerous forms of its females which mimic inedible Red-bodied Swallowtails, such as the Common Rose and the Crimson Rose.

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1. CITRUS BUTTERFLY / LEMON BUTTERFLY Small citrus butterfly Papilio demoleus Large citrus butterfly Papilio polytes Papilionidae: Lepidoptera • Most destructive pests of citrus seedlings and also main crop. The pest commonly found defoliating the sapling and young trees. • The pest is widely distributed from Formosa to Arabia including Burma, Bangladesh, Sri Lanka, India and Pakistan. • It is found in almost all citrus varieties though Malta (Citrus sinensis) is its preferred host. It can feed and breed on all varieties of cultivated or wild citrus and various other species of family Rutaceae. • Its range indicates the butterfly's tolerance and adaptation to diverse habitats. It is to be found in savannahs, fallow lands, gardens, evergreen and semi-evergreen forests and shows a preference for stream and riverbeds. • In India it is mostly found in the plains but can be found on the hills of peninsular India and up to 7000 feet in the Himalayas. It is common in urban gardens and may also be encountered in wooded country. Marks of identification Adults: • It is particularly abundant during and after the monsoons. Papilio demoleus Papilio polytes


Papilio demoleus

Papilio polytes

Freshly hatched caterpillars are dark brown and soon develop irregular white markings on their body giving them an appearance of bird’s excreta. When full grown, it turns deep green and cylindrical in form and measures about 40-50 mm in length with a hump like appearance in front and has a horn like structure on the dorsal side of the last body segment. • When disturbed, orange colour osmeteria will come out of head region, to evade enemies. • The caterpillars feed voraciously on tender leaves right up to the mid ribs and defoliate the entire seedlings or the tree leaving behind the only mid ribs. Besides citrus, it also attacks ber (Zyzyphus jujuba) only. Biology • The female Lime butterfly goes hurriedly from plant to plant, laying a single egg at a time on top of a leaf which it holds onto unsteadily with its legs, and flying off as soon as the egg is laid. The egg is round and light yellowish in colour. • The newly hatched caterpillar stays in the middle of the upperside of the leaf. The first few instars of the caterpillar resemble bird droppings and this helps them escape predation while remaining in moderately open places. The caterpillars are yellow-olive greenish with a white spiracular band. There is white marking on the 8th and 9th segments of the caterpillar which resemble a white patch of uric acid deposited in a bird's droppings. As the instars progress, this resemblance is lost. The caterpillars now turn uniformly pale green with a white sub-spiracular band. An additional black band is developed on the 4th and 5th segments with two black and two bluish spots on them. The 8th and 9th segments, which earlier provided the camouflage markings now develop a brown and white band. At this stage, the caterpillars are forced to inhabit secluded places. When disturbed, orange colour osmeteria will come out of head region, to evade enemies. • Despite their two stage camouflage scheme, some caterpillars are found by parasitic wasps (Chalcid Wasp, Braconid wasp) which lay dozens of eggs in them. The parasitic wasp larva eats the caterpillar from the inside. Initially the vital organs are avoided, but by the time the caterpillar is ready to pupate even the vital organs are consumed. Soon after the caterpillar pupates, the parasitoids emerge from the pupa thus killing it. •

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(Braconid parasitoid Wasp Apanteles Spp. Cocoons on Papilio demoleus larva, commonly seen in Citrus Garden at College Farm, Jagtial)


The pupa is comparatively big in size, located on underside of leafs and twigs. The pupa is light green and unmarked. It has two projections to the front on its head and also one on its thorax. It resembles that of the Papilio polytes. The difference being that the Common Mormon pupa has a deeper cut between the projections and its abdomen is more protruded on the sides, having a small point. When situated among dry objects, the pupa tends to turn light grey-brown and develop dark brown and black striation. Hibernation in pupal stage is seen. Management • In small orchards and nurseries with mild infestation, hand picking and destruction of various stages of the pest present, helps in mitigating the trouble. • Field release of parasitoids Trichogramme evanescens and Telenomus sp on eggs • Brachymeria sp on larvae and Pterolus sp. on pupae. • In large orchards and big nurseries spray monocrotopohs (1.5ml/L) / DDVP (1ml/L) for early larval instars. • Spray endosulfan (2ml/L) for late instars. •

2. CITRUS FRUIT SUCKING MOTH Othreis (Eudocema) materna Othries (Eudocema) fullonica Othries (Eudocema) ancilla Noctuidae: Lepidoptera • About a dozen species of Othreis (Ophideres, Eudocema) have been so far recorded damaging citrus fruits. • The important species are Othreis materna, O. fullonica and O. ancilla. • Serious pest of citrus fruits. • Adult is the damaging stage • Also attack pomegranate, mango, grapes etc • Adult pierce the fruit and suck the juice • Rotting at the feeding site, and finally lead to Fruit dropping. Marks of identification Othreis materna Othreis fullonica Othries ancilla

The moth is having brownish forewings with a green band in the middle and yellowish hind wings having a half moon or kidney shaped black spots

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The moth is having brownish forewings and yellowish black hind wings with a half moon or kidney shaped black spot.

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The moth is having brownish black forewings with a white stripe and yellowish hind wings with a circular black spot in the middle.


All these moths have a strong elongated mouth parts (proboscis) wonderfully adapted for puncturing the rind of the fruit. • The larva is a cylindrical stout bodied semilooper having a dark brown velvety colour with cryptic markings. It is found commonly on weeds belonging to Menipermaceae and not on citrus. • This is the only group of insects whose caterpillars feed on foliage of other host plants (weeds nearby) and only the moths attack citrus fruits. They pierce the proboscis into fruits and suck the sweet juice there in. Their feeding injury opens the way for bacteria, which makes the fruit rot around the punctures and drops prematurely. • The fruits of mango, pomegranate, grapes etc are also damaged by moths. • The moth damage lead to premature dropping of the fruits, and also rotting at the site of sucking. Biology • Spherical eggs are laid singly on the weed hosts (climber) like Cocculus pendulus, C. hirsutus and Tinospora cardifolia which grow along fence or hedges around the orchards. Incubation period is about 3-4 days. • On hatching the semilooper (caterpillars) feed on leaves of the wild hosts and pupates inside the leaf folds. Larval period is 13-17 days and pupal period is 12-18 days. It is found commonly on weeds belonging to Menipermaceae and not on citrus. Management • The weeds found around orchards should be destroyed. Destroy the weed host Tinospora cardifolia and coccules pendules • Trap Crop: Grow tomato as trap crop to attract moths. • Moths can be caught with light torches and killed. • Bagging of fruits with polythene (500 gauge) or paper covers has been suggested. This method though effective is rather expensive and non practicable on large scale. • Creating smokes in the orchards after sunset may keep the pest away but this is also rather laborious and unpracticable. • Poison baiting has been found quite effective it also kills the fruit flies (100 grams of gur/molasses + malathion 50EC 0.05% (1ml/L) + 1L water). Keep the bait suspension in small bowls, to attract moths. • Spray carbaryl 50WP @ 4gm/L or endosulfan 35EC @ 2ml/L.

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3. CITRUS LEAFMINER (CLM) Phyllocnistis citrella Gracillariidae: Lepidoptera • Pest of plants of rutaceae family. It infests all citrus fruits, but prefers sweet oranges. • Native to Asia, but has recently invaded most of the countries. • The pest is active all round the year, except during severe winter (December – February) but maximum damage is caused during May-June and also during AugustOctober, if the temperature is high enough. Marks of identification & biology • Adults of the CLM are minute moths with a 4 mm wingspread. It has white and silvery iridescent scales on the forewings, with several black and tan markings, plus a black spot on each wingtip. The hind wings (fringed) and body are white, with long fringe scales extending from the hindwing margins. Adults generally are too minute to be easily noticed, and are active diurnally and in the evenings. • CLM is most easily detected by its meandering serpentine larval mine, usually on the ventral side of the leaf.

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Eggs of CLM are laid singly on the underside of host leaves. Egg eclosion occurs within two to 10 days. Larvae immediately enter the leaf and begin feeding. Larvae are minute, translucent greenish-yellow, and located inside the leaf mine. Larvae make serpentine mines on young leaves (sometimes also young shoots), resulting in leaf curling and serious injury. Leaf mines are usually on the ventral leaf surface, except in heavy infestations when both leaf surfaces are used. Usually only one leaf mine is present per leaf but heavy infestations may have two or three mines per leaf, and up to nine mines on large leaves. As with similar leafminers, larvae are protected within the leaf during their feeding cycle. Larvae have four instars and development takes from five to 20 days. Pupation is within the mine in a special pupal cell at the leaf margin, under a slight curl of the leaf. Pupal development takes six to 22 days. Adults emerge about dawn and are active in the morning; other activity is at dusk or night. Development time totals about 13 to 52 days. Adults live for only a few days.

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Nature & Symptoms of damage: • This is the pest of nursery and main field, but most harmful insect of citrus nursery. • Its infestation coincides with the flush periods. • Larvae feed in epidermis of leaves making serpentine silvery mines usually on the ventral side. The serpentine mines appear silver colored because air is entrapped in these mines. • When the infestation is severe, mines also appears on dorsal side of the leaves. • These mines are filled with a central line of frass. • Tiny pupae can be seen in the damaged leaf in the mines. Such leaves are folded from the edge due to spinning of cocoons by the larvae. • Leaves get distorted, crumpled and curled from margins towards inner side. • Ultimately, the damaged leaves dry up and fall down. • Mines appear on tender twigs also. • Mines also appear on fruits in severe cases. • Severe defoliation may occur, which results in reduced growth of nursery plants. • The leaves folded due to damage by leaf miner serves as shelter site for mealy bugs, grey weevil, citrus psylla and spiders. • The damage caused by the hungry little caterpillars can leave the trees vulnerable to secondary infections, including citrus canker bacteria, Xanthomonas axonopodis.


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4. CITRUS PSYLLID / ASIAN CITRUS PSYLLID Diaphorina citri Psyllidae: Homoptera • The Asian citrus psyllid (ACP), an aphid-like insect, is a serious pest of all citrus and closely-related plants because it can transmit the disease huanglongbing (HLB) when it feeds on the plants’ leaves and stems. HLB is the most devastating disease of citrus in the world. • The Asian citrus psyllid is found in tropical and subtropical Asia, Afghanistan, Saudi Arabia, Reunion, Mauritius, parts of South and Central America, Mexico, the Caribbean and the United States. • The Asian citrus psyllid feeds mainly on Citrus spp., several other genera all in the family of Rutaceae. • Direct injury caused by ACP results from the withdrawal of large amounts of sap from the plant as they feed and produce copious amounts of honeydew. The honeydew coats the leaves of the tree, encouraging sooty mold to grow. • However, the most serious damage caused by ACP is due to its ability to effectively vector the phloem-inhabiting bacterium Candidatus Liberibacter asiaticus that causes Huanglongbing (HLB). HLB is the most devastating disease of citrus in the world. Symptoms of HLB include yellow shoots, with mottling and chlorosis of the leaves. The juice of the infected fruit has a bitter taste and the fruit's skin may retain some green coloration even though it is ripe. Infected trees eventually die of the disease. The

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Management: • This insect is very difficult to manage under nursery conditions as its life cycle is very short and there are 16 overlapping generations in a year. • Prune heavily the affected parts during winter and burn. • Spray with fish oil rosin soap and nicotine sulphate compound at 1 : 1 + 50 parts of water in early stages of infestation. • Sprinkling of neem cake solution on trees @ 250 gms of neem cake mixed in 4-5 lit of water. • Spray 500 ml fenvalerate 20 EC (fenvalerate) or 1000 ml cypermethrin 10 EC, or 1250 ml triazophos 40 EC or 1875 ml chlorpyriphos 20 EC or 200 ml Imidacloprid 200 SL in 500 litres of water during April-May and again during September-October. • Spraying the plants with Methyl Demeton (0.03%) and Phosphamidon (0.035%) at the emergence of new leaves is highly beneficial. • Application of Phorate 10 G (2.5 kg a.i./ha) applied one day before planting is effective in reducing the larval population of leaf miner.


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The Asian citrus psyllid is 3 to 4 mm long with a brown mottled body. The head is light brown. The wings are broadest in the apical half, mottled and with a dark brown band extending around the periphery of the outer half of the wing. The insect is covered with a whitish waxy secretion, making it appear dusty. Adults live for more than a month. Nymphs are generally yellowish orange in color, with large filaments confined to an apical plate of the abdomen. Nymphs pass through 5 instars. Nymphal duration 15-47 days.

The eggs are approximately 0.3 mm long, elongate and almond-shaped. Fresh eggs are pale in color, but then turn yellow and finally orange at the time of hatching. Eggs are placed on plant tissue on the tips on growing shoots, and between unfurling leaves. Typically there are 9-10 generations per year.

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once flourishing citrus industry in India is slowly being wiped out by dieback. This dieback has multiple causes, but the major cause is due to HLB disease. This pest acts as a vector for spreading the 'greening' disease.


Management: • Yellow panel traps at a density of 50 traps per square mile. • Collect and destroy the damaged plant parts • Spraying with systemic insecticides at flush growth periods • Spray malathion 0.05% or monocrotophos 0.036% or carbaryl 0.1% or methyl parathion 0.05%. • Encourage the activities natural enemies such as Syrphids and Chrysopids 5. CITRUS MITES RUST MITE Schizotetranychus hindustanicus Tetranychidae: Eriophyidae • These mites scrape the surface and suck sap causing large number of whitish spots. In each spot four or five mites may be seen. Even when mites disappear the whitish spots remain. • Spray Dimethoate 0.03% and there should be at least a fortnight interval between spraying and harvest. Or spray Wettable Sulphur 3-5 gms/lt of water.

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6. BARK EATING CATERPILLARS Indarbela tetraonis Inderbela quadrinotata Tetragridae (Metarbelidae): Lepidoptera • Occasionally these pests in large numbers cause severe damage especially to old trees. • The freshly hatched larvae feed on tree trunks, but when strong enough they bore inside the trunks and moves about inside the concealed silken gallery and feed on the

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LEAF MITE Eutetranychus orientalis The mites damage the fruits by causing russetting and render the fruits unfit for export. The insects feed on the leaves and produce multiple grey spots. The affected leaves defoliate. Mites can be controlled by application of Dicofol (1.5 ml/litre of water) or Wettable Sulphur (3.0 g/litre of water) or Monocrotophos (1.5 ml/litre of water).


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bark by scraping which interrupts the translocation of cell sap and adversely affects the growth and ultimately fruit setting capacity of the tree. Huge webby mass conspicuously plastered on the stem near forks or angles of branches and the tree trunk is the clear indication of damage by this pest. Only one caterpillar is seen in a gallery. The pest is satisfactorily controlled by removing the webbing followed by plugging the holes with Cotton wool soaked in the 2-5ml of Dichlorvos 76EC solution (20ml/10 litres of water). The holes are then sealed with mud. The best time for its control is September-October and the operation should be repeated in January-February.

7. CITRUS APHIDS Black Aphid : Toxoptera auruntii Brown Aphid : Toxoptera citricida Aphididae: Homoptera

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Feed on tender foliage and flowers. Transmit tristeza virus disease. Nymphs and adults suck the sap of leaves Wilting and flower dropping Infested leaves - cup shaped and crinkled Growth of the plants is hindered. Use yellow sticky trap Spray with methyl demeton (Metasystox) or dimethoate (Rogor) 2ml /lit

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8. CITRUS BLACKFLY Aleurocanthus woglumi Aleyrodidae: Homoptera • Nymphs-are flattened, oval in shape and scale like in appearance. • Adult-minute insect, shiny black with grey dusting on the body. Wings are extending beyond the tip of the abdomen. • The cell sap is sucked from the leaves (piercing stylet) • Leaf curling is the primary symptom, and eventually leaves fall off immaturely. • Honey dew secretion, development of sooty mould fungus. • Leaf turns to black in colour and affects photosynthetic activity of the leaves. • Affected trees produce - few blossoms which develop into insipid taste fruits, fruits turn black colour. • The infestation is more intense in more dense and shady orchards.


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Collect and destroy the damaged plant parts along with nymphs, pupa and adults Spray with 2 ml of chloropyriphos per litre of water, followed by a second spray after 15 days with 1.5ml of monocrotophos Female lays eggs on lower surface of leaves in a form of three (15-22 eggs/whorl) whorls, and hence the entire plant canopy should be drenched with the solution. Encourage activity of parasitoids, Encarsia sp., Eretomocerus serius and predators like chlysoperla sp.

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10. CITRUS MEALYBUG Planococcus citri Pseudococcidae: Homoptera • These are un-armoured soft-scale insects • Adults: The female citrus mealybug is wingless and appears to have been rolled in flour (hence the name). A fringe of small waxy filaments protrudes from the periphery. The male is small, but with its wings and tail filaments. • Eggs: The oblong, yellow eggs are enmeshed in a dense, fluffy, white ovisac. • Crawlers: The tiny crawler is oval and yellow, with red eyes. The antennae are rather distinct. • Nymphs: Female nymphs resemble the larger adult females. Male nymphs are narrower and often occur in a loose cocoon. • Host Plants: Citrus mealy bugs have been collected from at least 27 host plant families. Many ornamental plants grown in greenhouses are susceptible to attack.

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9. CITRUS SCALES • Armoured scales (Aonidiella auriantii, A. citrina, A. orientalis, and Chrysompahlus aonidum.) • Armoured scales, which have hard cover separate from the body providing protection to the body underneath. • The armoured scales damage the fruits and form as blemishes at low levels of infestation and in severe cases, they damage the tree badly. The soft scales secrete honeydew on which sooty mould fungus grows. • Hard armoured scales are difficult to control.


Damage: Citrus mealy bugs damage hosts by sucking out plant sap, by excreting honeydew in which sooty mold can grow, and by causing distorted growth and premature leaf drop with their toxic saliva. They further disfigure plants by secreting cottony wax. Infested plants usually die unless the pest is controlled. • Life Cycle: Because female citrus mealy bugs have no wings, they must be transported to the proximity of the next host plant. They can, however, travel short distances by crawling. The immatures can be blown about. Males are small, winged insects. After mating, each female lays up to hundreds of eggs in a dense, fluffy secretion called the egg sac or ovisac. Within a few days, new mealybugs (crawlers) hatch and begin to squirm out of the ovisac. Light infestations are easily overlooked because the mealybugs tend to wedge into crevices on the host plant. As their numbers increase, mealybugs of all sizes can be seen crawling around or feeding on all exposed plant surfaces. Management: • Control of citrus mealybugs is amazingly difficult. Growers merely discard infested plants rather than trying to rescue them from citrus mealybugs. • Collect and destroy the damaged leaves, twigs and stems • Debark branches and apply methyl parathion paste • Use sticky trap (5cm length) on fruit bearing shoots • Spray dichlorvas 0.2% in combination with fish oil rosin soap 25g/lit • Single soil application of aldicarb 10G at 50g/tree at the time of pruning • Spraying of trees with methyl parathion 2ml or monocrotophos 1.5ml per /lit of water • Soil treatment with chlorophyriphos apply on the near the tree trunk • Spraying of trees with acephate, methomyl, or chlorpyriphos. • Field release of Australian lady bird beetle Cryptoleamus montrouizeri 10 per tree • The lady beetle Cryptolaemus montrouzieri and parasitic wasps Leptomastix dactylopii and Anagyrus pseudococci attack citrus mealybugs.

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Lecture 31: (INSECT PESTS OF GRAPES) 31. Major insect pests of grapevine-distribution-marks of identification biology-nature and symptoms of damage and management strategies of flea beetles, thrips and mealybug; Minor insect pests-stem girdler, stem borer, Spodoptera, Helicoverpa and root grub and their nature and symptoms of damage and management practices.

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The adult beetles scrape the sprouting buds after each pruning, and chew holes in the sides of newly developing grape buds. Damaged buds fail to sprout. The beetles and grubs also feed on tender shoots and leaves, and tendrils causing substantial damage, resulting small holes on leaves. The tender shoots may wither and drop down. The losses are heavy when the sprouting buds are damaged after forward pruning. Larvae and adults feed on the upper and lower leaf surfaces – leaf injury. Their feeding on mature leaves, cause elongated holes on the leaf Lamina, giving it a shot hole appearance. Grubs damage roots. The adults start laying eggs about one month after emergence and continue from middle of March to meddle of October. The female oviposit just beneath the loose bark of the vines or in the soil. Eggs are laid singly or in groups (220-570 egg/female). Eggs are agar shaped creamy white when fresh and turn to yellowish subsequently. Egg period is 4 days. On hatching the grubs drop down to the water basin and furrow into the soil and they feed on the cortical layer of roots. Grub period 6-7 weeks. Pupation takes place in an earthen cell pupal period 7-11 days. Total life history occupies 52-54 days. Adult lives for about 8 months. Remove the loose bark at the time of pruning to prevent egg laying Shake vines to dislodge adult beetles Collect into trays containing kerosenated water and destroy them Removal of loose bark of the stem and applying paste of Copper Oxychloride and Carbaryl 50% WP after forward pruning to exposes and kills the beetles. Spraying of insecticides like Carbaryl (0.15%) or Quinalphos (0.05%) from the fourth day after pruning at an interval of 3-5 days until the emergence of the leaves is effective in protecting the sprouting bud from the attack. The spraying should preferably be carried out in the evening.

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1. FLEA BEETLE Scelodonta strigicollis Chrysomelidae: Coleoptera • Major pest of Grapes • Adult-Reddish brown, shiny with six spots on elytra • Grub–brown in colour and black colour head


2. THRIPS (Taamara Purugu) Rhipiphorothrips cruentauis Thripidae: Thysanura • One of the most destructive pests of grapevine India. • It also feeds on rose, jasmine, cashew and Calotropis. • Found throughout the year. • Thrips are oval, pale brown / black colored tiny insects found on underside of leaves, which deposit eggs on the underside of the leaves. • Nymphs yellowish brown color, with red abdomen. • Both the nymphs and adults suck cell sap from the lower surface of the leaf. • The injured surface is marked by a number of minute spots thereby producing a speckled silvery effect, which can be detected from a distance. • In case of heavy incidence, the leaves may dry up and drop off the vine. • Thrips also attack blossoms and newly set berries. • The affected berries develop a corky layer and become brown on maturity. • Fruit setting is poor and yield is considerably reduced.

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Adults appear in March and lay eggs on the underside of leaves by making slits in leaf tissue, placing one egg in each, slit. Each female lays about 50 eggs. The egg is dirty white and bean shaped. Eggs hatch in 3-8 days, young nymphs on hatching feed on the underscore of leaves by rasping the surface and sucking the cell sap that oozes. Nymphal period 9-20 days. Pupate on leaves and pupae possess locomotion and crawl when disturbed. Pupal period is 2-5 days. Adult emerge and also feed like nymphs. Reproduction with or without fertilization. Fertilized eggs give rise to female and unfertilized ones to male. Alternate spraying of insecticides like Phosphamidon (0.05%) or Monocrotophos (0.1%) or Malathion (0.05%) offer a good control over the pest. Prophylactic sprays immediately after flowering and during fruit set is essential.

3. GRAPE MEALY BUG (Pindi Purugu) Maconellicoccus hirsutus Pseudococcidae: Homoptera • Among the mealybug species infesting grapes in India, the pink mealybug Maconellicoccus

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It is a serious pest on grapevine having compact bunches of fruits like Thompson seedless variety. Anab-e-shahi having loose bunches in less infested with mealy bugs. Clusters of mealy bug with white mealy coatings, such the sap and making berries or fruits unfit for consumption. Mealy bug is a soft insect with oval shaped flat body. The nymphs of mealy bugs generally referred, as crawlers are pink to light orange in colour.

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hirsutus and the citrus mealybug Planococcus citri are found causing severe loss in many grape growing areas of Maharashtra, Karnataka, Andhra Pradesh and Tamil Nadu.


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The adult female mealybugs are pinkish (M. hirsutus) or yellowish white (P. citri) and sparsely covered with white wax. Each female mealybug deposits 350-500 eggs in a loose cottony terminal ovisac during a week's time. These eggs are orange in colour (M. hirsutus) (Fig. 3) or yellowish white (P. citri). They hatch in about 5 days. The first instar nymphs are also called as crawlers, which are mobile. They settle on the plants, start sucking the sap and form the colonies. Crawlers are orange in colour (M. hirsutus) or yellowish white (P. citri). The male and female mealybugs are similar in early stages. The female passes through three nymphal instars while male passes through four nymphal instars. The total nymphal period is 19 days for male and 21 days for female. The male nymph forms a cottony cocoon in which the pupal stage is found mainly in the winter season. The adult male has a pair of wings and a pair of halteres. All the stages of the female mealybug are similar (Fig. 4). Males are very rare and female mealybugs are commonly found causing the damage in the field. Mealybug completes the life cycle in about 30 days. Without mating, they are known to reproduce partheno-genetically throughout the year.

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They are found to be active from June-August and again from November-March under peninsular India conditions. Nymphs and adults of mealy bugs suck sap from the leaves, tender shoots, and the fruits. Infestation of the growing point especially with the pink mealybug results in malformation of leaves and shoots tips. Leaves show characteristic curling symptoms similar to that of a virus. A heavy black sooty mould may develop on the honeydew like droplets secreted by mealy bugs. If the flower blooms are attacked the fruit set is affected. When the fruits are infested they can be entirely covered with the mealy bug. The infestation may lead to fruit drop or the fruits remain on the shoots in a dried and shriveled condition. Sooty and sticky bunches harbouring mealybugs and their white cottony wax masses are unfit for marketing as table grapes. Raisins cannot be prepared from such infested bunches. The pest attack weakens the grownup vines. In case of severe mealybug infestation young vines often die. The grape mealybug causes losses up to 100 per cent in severe cases in the vineyard Various species of ants feed on the honeydew. Ants drive away the natural enemies and act as carriers of bugs.

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Management of Mealybugs (As recommended by NRC Grapes, Pune)

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Prevention is better than cure. This principle is highly applicable in the management of grape mealybug. Mealybugs are hard to kill pests on several crop plants. They form colonies in protected areas like cracks and crevices. All the stages of the mealybugs are covered with waxy coating and therefore it is difficult to control the mealybugs with conventional insecticides. Cultural, mechanical, biological and chemical methods of control have to be adapted throughout the year to contain the mealybug population thus preventing the loss caused by the mealybugs. 1. Collection and destruction of the mealybug - infested bunches at the time of harvesting in March-April. 2. Collection and destruction of all the pruned material from mealybug infested gardens in April/May. 3. Removal of loose bark and destruction of the debarked material in April/May. Pasting it with a mixture of Copper Oxychloride and Carbaryl after October pruning helps to minimize the pest population. Pasting a grease band of 5cm width on the main stem of vine at 150 cm from the ground after forward pruning prevents the crawlers from reaching the bunch. (Sticky trap on fruit bearing shoots) 4. Removal of weeds and alternate host plants harbouring the mealybugs in and around the vineyards throughout the year. 5. Locating the ant colonies and destroying them with drenching of chlorpyriphos 20 EC @ 2.5 mL/L or apply malathion 5% dust @ 10 kg/ac in April-May, since the ants are associated with the buildup of mealybug population. 6. Swabbing/washing of trunk and cordons with 2 mL of dichlorvos 76 EC + 2 g of fish oil rosin soap in a litre of water in April-May. 7. Soil drenching with imidacloprid 200 SL @ 1.50 mL/L/plant in the basins around the trunk or through drip irrigation @ 400 mL/ ac in April-May. 8. Foliar spray with methomyl @ 1g/L after 30 days of soil drenching. Unlike the adults, the crawlers are free from waxy coating and therefore the crawler stage is the most effective for spraying pesticides. 9. Releasing the Australian ladybird beetle (Cryptolaemus montrouzieri) @ 5000/ha. in AugustSeptember to clear the mealybug population present on the plants. 10. Alternatively, two to three foliar sprays of Verticillium lecanii /Beauveria bassiana (2x108 cfu/mL/g) @ 5 g/L at 15 days interval in the rainy season (July-August) can be given. After Pruning • Steps No. 1-8 to be followed after foundation pruning should be repeated in OctoberNovember also. Step No. 7 has to be followed with preharvest interval of 60 days for imidacloprid. 9. Monitoring and destroying the mealybug colonies as and when seen on the trunk, stem, etc. from November to February. 10. Foliar spray of the following chemicals depending on the incidence of the mealybugs is recommended to keep the mealybug population under check. Insecticide Dose Pre Harvest Interval Buprofezin 25 SC 1.25 mL/L 40 days Methomyl 40 SP 1 g/L 61 days Dichlorvos 76 EC 2 mL/L 15 days Azadirachtin 1% 2 mL/L 3 days Chlorpyriphos 20 EC 2 mL/L 40 days 11. Releasing the Australian ladybird beetle (Cryptolaemus montrouzieri) @ 5000/ha during mid December – first fortnight of January. 12. One or two applications of dichlorvos 76% EC (2 mL/L) from mid February to the first week of March, if necessary, depending upon the incidence of mealybugs and time of harvesting. 13. One jet spray of water can be given on the bunches if the mealybugs are still present just prior to harvest to dislodge the mealybugs.


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Aspidiotus lataniae Aspidiotus cydoniae It is the most common pest found in the vineyards of Punjab. The adult female lays eggs in the crevices or loose bark of the vine, trunk and its arms. These insects suck the cell sap from the leaves, petioles, main veins and tender shoots of the grapevine. Weak shoot growth with appearance of golden-yellow leaves indicates the advanced stage of pest attack. As the arms become dry, wood-boring insects may cause further damage. Frequent attack in subsequent years leads to the death of the vine. The loose bark should be removed at the time of pruning. The encrustations should be scraped and the vine should be sprayed with Malathion (0.05%). Cuttings free from the infestation of the pest should be used for planting. Ants which act as carrier of the scales should be controlled to check the spread of the disease.

5. STEM GIRDLER/CANE GIRDLER Sthenias grisator Cerambyiicidae: Coleoptera • The adult beetles girdle around the main stem 15 cm above the ground level at night. • They also girdle the young green branches, which later dry up. • The adult beetle lays eggs in the girdled portion. • After the hatching of the eggs the grubs tunnel into the dry wood. • Girdling results in considerable damage to the plant. • During the day the adults hide on the lower side of the leaves or under the forking of the branches, but actively move about at night avoiding the light. • Grub - Head is dark brown colour, pair of strong mandibles. • Adult – Medium sized, grey coloured with a white spot in the center of each elytra.

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6. STEM BORER Celosterna scabrator Cerambyiicidae: Coleoptera • The adult beetle lays eggs on the trunk, branches or the stem and the grubs, which hatch, bore into the stem directly. • Wood dust and faecal matter at the base of the vine is indication of the borer activity. Revised during 2011

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Hand picking of the adults at night with the help of torchlight is effective. The beetles should be hand picked and killed as and when noticed. Since the eggs are also laid in the bark of the girdled branches which get dried up very soon, collection and burning away of such dried twigs from vineyards would be a good check against future outbreak of the pest. A piece of cloth is soaked in an insecticide solution like Chlorpyrifos and then wrapped around the stem. Spraying of Chlorpyrifos (0.1%) is also effective.

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The adults feed on the outer bark of the vine by scraping. The portion of vines above the damaged part has a sticky appearance. The leaves turn yellow in patches that resemble micronutrient deficiency, which ultimately dry and drop down.

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Sanitation in the orchard, removal of dead woods and loose barks regularly help in preventing the infection. The eggs can be eradicated by removing the bark of the infested vines and applying paste of Carbaryl (50WP) 6g + Copper Oxychloride 3ml + Dichlorvos 3ml + neutral pH sticker soap 1ml. Injecting Dichlorvos solution into the hole followed by sealing with mud or cow dung mixed with Copper Oxychloride in 1:3 ratio is also effective. The spread of the infection can be controlled by spraying the entire orchard with Quinalphos (0.06%) + Dichlorvos (0.08%).

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7. GRAPE LEAF ROLLER (Aaaku chuttu purugu) Sylepta lunalis • This is a serious pest in South India, which is most active in the months of AugustNovember. • Yellowish-green caterpillars roll the leaves from the edges towards the midrib and feed within by scraping the chlorophyll. • In case of severe infestation skeletonization & complete defoliation is observed. • Adult: Brownish moth with wavy lines. • Larva: Pale green with short hairs • A simple method to control the pest population is to collect and burn the infested leaves. • Spraying of Malathion (0.05%) or Endosulphan (0.05%) have been recommended for effective control of the pest.


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8. TOBACCO CATERPILLAR Spodoptera litura Noctuiidae: Lepidoptera • This pest is of common occurrence in Maharashtra and Hyderabad. • The adult moth lays eggs on the lower side of the leaves. • Young larvae feed on the lower epidermal layer of the underside of the leaf and make the leaf surface papery. • The larvae of the pest also feed on the leaves and inflorescence. • They cut down the rachis of the grape bunches. • The adult moths are most active during August-September. • Caterpillars can be effectively controlled by spraying of Chlorpyrifos (0.08%) or Carbaryl (0.125%) or Dichlorvos (0.1%). • A mixture of Methomyl (0.05%) and Wettable Sulphur (0.2%) is effective to control the larvae in its young stage of growth. • Use of pheromone trap is effective in catching the adult moths and also to know the population built up of the pest. Pod Borer: Helicoverpa armigera Root Grub: Holotrichia consanguina


Lecture 32: (INSECT PESTS OF CASHEWNUT) 32. Major insect pests of cashew-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of tree borer, shoot and blossom webber, tea mosquito bug and thrips; Minor insect pests of cashew - nature and symptoms of damage and management practices of leaf miner.

1. CASHEW TREE BORER Plocaederus ferrugineus Cerambyiicidae: Coleoptera • One of the major pests and normally found in old plantations where sanitation is poor. • Adult is a medium sized, dark brown longicorn beetle. • The full grown grub is white. • Grub feeds on soft tissues by tunneling in various directions and also feeds on wood when grown up. • Affected trees show yellowing and shedding of leaves and drying of twigs also. • In severe cases entire trees die. • Bored holes on trunk are plugged with excreta and reddish mass of chewed fiber. • Lays eggs under loose bark on the trunk or on exposed roots. The grubs on hatching bore in to bark and feed on soft tissue. Grub also enters root region through the barks and feeds on root tissue. The grub forms calcareous shell and pupates inside. Pupa is brown coloured and bean seed like. Total life history occupies 9-10 months.

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Remove dried branches dead trees and burn them. From the damaged portion remove grubs, pupae and adults by chiseling and destroy them. Infested trunks and roots may be swabbed with BHC 0.1% solution. Remove the soil around the base of tree upto 1 foot depth and apply 300-500 gms of BHC 10% dust per tree and cover it with fresh soil. Inject Pyrocone E 1% sol into the holes of tree trunk and plug them. Clean the bored holes and insert 1-2 tables of Aluminum phosphide in each hole and plug the holes.

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3. TEA MOSQUITO BUG Helopeltis antonii Miridae: Heteroptera • The mosquito bug, (Helopeltis antonii) is considered to be the most serious pest of cashew in India, and causes more economic loss to the crop than any other pest. It is estimated that this pest alone is responsible for damage of nearly 25% of shoots, 30% of inflorescence and 15% of tender nuts. It causes more than 30% economic loss by inflorescence blight and immature nut fall.

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2. CASHEW LEAF & BLOSSOM WEBBER CASHEW SHOOR & BLOSSOM WEBBER Lamida (Macalla) moncusalis Pyralidae: Lepoidoptera • Leaf and blossom webber, Lamida (=Macalla) moncusalis is reported to be a major pest in East-Coast, particularly in Tamil Nadu, Andhra Pradesh and Orissa. Another species, Orthaga exvinacea Hamps (Noctuidae) has also been recorded as pest on cashew, but it is of minor importance. Lamida spp. Is a major and regular pest, occurs all through the year. • The pest incidence is severe at the time of new flush by webbing the leaves and feeding on them. • Leaf and blossom webbers attack new flushes and inflorescences. • The caterpillars of this pest web the shoots and inflorescences together, remain inside and feed on them. Subsequently the webbed portion of the shoots and blossom dry up. Hence, it is called shoot and blossom webbing caterpillar. • The galleries of silken webs reinforced with castings and scraps of plant parts are indicative of the presence of caterpillars inside the webbed portion. • The incidence is found severe mostly on young trees. • Apples and nuts are also covered with webs. • The caterpillar feeds by scraping the upper green layer of apples and nuts when they are tender. It results in cracking of tissue and retardation in nuts development. • Adult is a medium sized dark brown moth. Males of L. moncusalis are dark, while the females are olive green. Females are found to mate only once during their life time. Females kept without mating, lay unfertilized eggs. The eggs are laid singly or in small groups of 3-5 on the leaves during night, more usually on the ventral surface and occasionally on the tender shoots, finely glued on to the surface. Freshly laid eggs are yellowish green in colour, ovoid, somewhat flat on the surface, but three broad pink bands appear across the surface a day later. The incubation period lasts 4 to 7 days. • The caterpillar is dark green in colour with yellow longitudinal bands and pinksish dorsal lines. Full grown larva measures 24.0 to 27.0 mm in length and the larval period is 16 to 24 days with 5 larval instars. • Pupation takes place in cocoons in the leaf webs. The pre-pupal period lasts 1-4 days and the pupal period 9-14 days. Freshly formed pupa is light yellow with greyish tinge at the thoracic region. The pupa is 13 mm long and 4.1 mm breadth. • Adult emerges by making a rupture in the pupa. Males have peculiar habit of resting on the dorsal side of the leaves with the tip of the abdomen raised and bent upwards. Life cycle is completed in 37 days on cashew and 41 days on mango. • Spraying carbaryl 50 WP 0.1% (@ 2g / lit) or chlorpyriphos 20 EC 0.05% (@ 2.5 ml / lit) at flushing period will control this pest effectively. • For better control where ever possible, the disturb webs before sprays.. • Three larval parasites recorded in Andhra Pradesh: Apantelus sp of family Braconidae (Hymenoptera) parasite population is found high in Guntur district during Jan-Feb.


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Nymphs and adults of this mirid bug suck sap from the leaves, young shoots, inflorescence, developing young nuts and apples. The injury made by the suctorial mouth parts of the insect cause exudation of a resinous gummy substance from the feeding punctures. The tissues around the point of entry of stylets become necrotised and black scab formed, due to the action of the phytotoxin present in the saliva of the bug, infesting the tender shoots / inflorescences at the time of feeding. These lesions turn pinkish brown in 24 hours and become black in 2-3 days. Feeding on tender leaves cause crinkling. Affected shoots show long black lesions and may cause die-back in severe cases. Infested inflorescence usually turns black and die, immature nuts may drop off. Heavily infested trees show scorched appearance, leading to the death of shoots and growing tips. Biology: The adult bug is reddish-brown, about 6-8 mm long with a black head, red thorax, black and white abdomen. The pest can easily be recognized by its peculiar pin-like, knobbed process projecting on the dorsal side of its mid thorax. The knobbed stalk resembles a miniature wireless mast arising from the top of the thorax.

• With their sucking mouth organs, they feed on cellular sap from young tissues of shoots and inflorescence. The adult usually feeds during early hours (6-10 am) and makes about 150 feeding punctures per day. The adults are poor flyers, generally fly below the bush and mating takes place mostly on the undersurface of cashew leaves. • Female bug lays eggs 24 hours after mating, deeply inserting it into the tender tissues of new shoots, leaf petioles and veins. Eggs are reniform and creamy white. The presence of chorionic threads projecting outside the tissues is indicative of the presence of eggs inside. They are laid singly and a single female bug lays, on an average, 50 eggs. The incubation period of the egg is on an average 5-7 days, at a temperature range of 24-32 oC and relative humidity of 50-100 per cent. • About 60% of the eggs normally hatch out as nymphs. Young nymphs feed on tender leaves which later become necrotic.The nymphs are wingless and smaller, but otherwise resemble the adults. The young nymphs are orange coloured and ant-like. • A nymphal period with 5 instars is of 10-15 days. The first instar is completed in 1.9 days, second instar in 2.2 days, third in 2.8 days, fourth instar in 2.8 days and fifth instar in 3.2 days and thus nymphal period completes within 13-15 days. Nearly 60 per cent nymphs survive and moult as adults. . The female bug lives for about 7 days, while the longevity of male is 9-10 days. The life-cycle is completed in 25-32 days. The bugs resembles mosquito in sitting position and hence this pest is known as ‘mosquito bug’. Seasonal incidence: • During rainy season, mosquito bug population is not present in the field but just after rain (December onwards), when the cashew trees are in their most active growth phase with the new flush and tender inflorescence, the condition becomes quite congenial for the multiplication and feeding and during this period this pest becomes abundant. The pest population reaches its peak, invariably in February–March i.e., in the third month of commencement of the population builds up when the trees are in full blossom.

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Young trees are liable to suffer more in a longer period than older trees, because of the availability of succulent flush throughout the year. The population build up of the pest is negatively correlated with meteorological factors like minimum temperature, relative humidity and rainfall and positively correlated with sunshine. Alternate hosts: • Neem is known to be the main host of this pest (from which it was identified). The alternate hosts of the mirid bug are guava, cocoa, mahogany, cinchona, cotton, apples, grapes, drumstick, black pepper and jamun. Management: • For efficient management of mosquito bug, it is essential to check the build up of the pest population on cashew as well as on the alternate hosts such as guava, neem, cocoa, drum stick, mahogany and black pepper in the vicinity of cashew plantations. Remove the volunteer (self-sown) neem plants in and around cashew plantations. • Among the various insecticides tested, monocrotophos 36 WSC 0.05% (@ 1.5 ml / lit) one spray at flushing season (Sep-Oct), endosulfan 35 EC 0.05% (@ 1.5 ml / lit) one spray at flowering season (Nov-Dec.) and carbaryl 50 WP 0.1% (@ 2g / lit ) one spray at fruiting season (Jan-Feb) were found to be superior in checking the pest. If the chemical is sprayed with motorized knapsack sprayer, the concentration of the chemical has to be doubled. • Spray well in advance before the insect inflicts damage to the crop. Through foliar coverage is a must. The same insecticide should not be repeated in the second round. Avoid indiscriminate use of synthetic pyrethroids as it causes flare-up of sucking pests. Insecticides should be sprayed in evening hours to avoid toxicity to the insect pollinators. • If no new growth is seen from the dried up shoots or branches in spite of spraying insecticides in the severely infested cashew trees, such shoots or branches should be split open for confirmation of "die back" disease which is caused by fungal pathogen (Botrydiplodia theobromae). If the discolouration of sap wood is seen, it indicates the manifestation of die back disease. For controlling this disease, pruning of dried shoots or branches, swabbing the cut surfaces with Bordeaux mixture paste (10%) and spraying the tree with Bordeaux mixture (1%) are required in addition to insecticidal sprays. • At the out-break situation, the management programme against this pest should be launched on large scale community basis as the efforts made by an individual farmer may not be of much use. • The eggs of the mosquito bug are naturally parasitized by Telenoums sp. and Erythmelus helopeltidis. Spiders such as Oxyopes schireta, Phildippus patch and Hiyllus sp. are efficient predators and feed on nymphs and adult mosquito bug.

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4. FOLIAGE THRIPS Selenothrips rubrocinctus Thripidae: Thysanoptera • Three species of thrips viz. Selenothrips rubrocinctus, Rhipiphorothrips cruentatus and Retithrips syriacus have been reported as foliage pests of cashew of which S. rubrocinctus is of economic importance. • This thrip is widespread throughout the tropics; however, it is not considerd to be a major pest because its infestation is restricted to a small area. Symptoms of damage: • Adult and young thrips are seen in colonies on the lower (abaxial) surface of leaves and suck the sap. As a result of rasping and sucking activities, the leaves of infested

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5. CASHEW LEAF MINER Acrocercops syngramma Gracillariidae: Lepidoptera • It is also one of the major pests regularly occurring at the time of new flesh generally during June-July and Jan-Feb, causing serious damage to the tender foliage of postmonsoon flushes. • Young caterpillars soon after hatching, start mining the epidermal layer on the upper surface of the tender cashew leaves, leaving tortuous markings. Later on, the thin epidermal mined areas swell up. As a result, the affected areas form blistered patches of greyish white colour. When the infested tender leaves mature, big holes are manifested in the damaged areas. The results of injury are the permanent damage to the young leaves which are shrivelled, dried and shed prematurely. Nursery seedlings and young plantations are more prone to the infestation of this pest than the older ones. Normally 3 to 8 blisters and as many as eight caterpillars are observed on a single leaf. • Generally young plants are more affected by this pest.

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young trees become pale-brown and crinkled with roughening of upper surface. In severe cases, there will be shedding of leaves and even stunting of growth. • The population of thrips varies from tree to tree in the same area and the insects do not feed indiscriminately, some trees even remain uninfested while others are heavily infested. The trees which produce leaves after the onset of monsoon are found free from attack because leaves become old during summer months and hence are not normally infested. • The leaves of post-monsoon flushes about full size but not mature, are mostly invaded by thrips, but as the leaves become old, a number of newly hatched nymphs decline to accept the old leaf tissue and finally the remaining population disperses. • In most of the young plants, thrips are found to appear on the foliage and cause heavy damage, particularly in summer months. The population increases during the dry season from December to January to a peak in April-May and then rapidly declines during wet season. Biology: • The eggs are inserted singly in the epidermis of the leaf and each is covered with a drop of excremental fluid which dries to form a black disc like pellicle. • The nymphs emerge in about 10 days, wander freely and carry a drop of excremental fluid at the apex of the abdomen which is carried upraised and is lowered at intervals to deposit the droplet which gives a small brown stain when it dries up. • The nymphs commonly known as red-banded thrips are distinguished by their greenish yellow colour and recognized by bright red bands across the first and last abdominal segments, while the adults possess a highly polygonally reticulate body with needlelike terminal antennal joints and broad wings with dark strong stiff setae. • The nymphs feed for 10 days, involving a mono-feeding, pre-pupal instar lasting for a day and non-feeding pupal instar for further 2-3 days. • Winged dark-brown adults emerge which have mandibular and maxillary stylets similar to those of nymphs. The female can oviposit soon after emergence and may produce upto 50 eggs during her life of about a month. Management: • Spraying with endosulfan 35 EC 0.05% (@ 1.5ml / lit) at the time of emergence of tender shoots and panicles is very effective for its control. • Spray DDVP (Nuvan) or Fenitrothion @ 0.05% concentration or with neem cake solution (soak 1 kg neem cake in 20 lts for 24 hrs, dicant and spray without dilution).


Biology: • The adult is a silver grey moth which lays eggs on tender leaves. Freshly hatched larvae are pale white in colour and the head is brownish yellow. At maturity, it changes into cherry red colour. The larvae are almost cylindrical, tapering posteriorly. The larvae remain active most of the time under ‘blister’. The caterpillars make their own way out of the mined areas and fall to the ground for pupation. The length of fully grown larvae is 5-9 mm. The total larval period ranged between 10 to 15 days. • Pupation takes place mostly in the soil and in some cases in the leaf-folds in a thin membranous cocoon. While pupating, they secrete a membranous protective covering. The pupal period lasts 7 to 9 days. The life cycle of this pest is 20 to 25 days.

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Spray with BHC 0.1% or Endosulfan 0.05% or Phosphamidon at 0.05% or Monocrotophos 0.03% Synchronizing with when plant puts forth new flush (OctoberNovember). The leaf miner (Acrocercops syngramma Meyrick.) is a major pest causing serious damage to the tender foliage of post-monsoon flushes.

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Lecture 33: (INSECT PESTS OF POMEGRANATE & GUAVA) 33. Major insect pests of pomegranate and guava-distribution-marks of identification-biologynature and symptoms of damage and management strategies of butterfly (pomegranate), tea mosquito bug and mealybug (guava); Minor insect pests of pomegranate and guava distribution-marks of identification-biology-nature and symptoms of damage and management strategies of fruit fly and spiraling whitefly.

1. POMEGRANATE BUTTERFLY (Anar Butterfly) Virachola Isocrates Lycaeniidae: Lepidoptera • Other hosts include apple, guava, and tamarind. • The flush brown butterfly has an orange spot on each of the fore wings and black spots on the hind wings. The butterfly has tact like extension at the lower margin of hind wings. It is active in bright sun. • The caterpillar is dirty brown and has short hairs on its body.

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2. TEA MOSQUIOT BUG ON GUAVA (jaamapandu kutte doma) Helopeltis antonii Miridae: Heteroptera • Nymph and adult: Reddish brown, elongate bug with black head, red thorax black and white abdomen • Nymphs and adults make punctures on petiole, tender shoots and fruits • Brownish black necrotic patches develop on foliage • Elongate streaks and patches develop on shoots • Corky scab formation on fruits Revised during 2011

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The caterpillar bores into the fruit and no entry hole can be made out. The fruit appears healthy, but the caterpillar inside will eat the seeds characteristically often the anal segment of the caterpillar can be seen plugging the bored holes. The caterpillar may cause rotting inside the fruit It is only when the grown up caterpillar comes out, a round hole is seen. Juice will ooze out of the hole. It is too late for any treatment. A single fruit may have half dozen caterpillars. The butterfly covers on the tender fruit and lays eggs. The eggs are laid singly on tender fruits and flowers also. Pupation takes place outside on fruit stalk or stem or inside the fallen fruits. Egg period 7-10 days. Larval period is 18-47 days and pupal period 7-34 days. The total life history occupies about 1-2 months. Four over lapping generations are seen in a year. Though expensive bagging of fruits with polythene or paper bags or cloth bags as soon as the fruits are set prevent pest attack. Destruction of fallen infested fruits checks further spread. During flowering season spray with Carbaryl 50% at 0.2% concentration

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A bug may tab in about 50 places on a single fruit. On tender fruits, the spots may coalesce and finally crack. Such tender fruits drop down. If the bug has pierced into twig, black linear scars will result If tender leaves are pierced there may be reddish small streaks and the twigs with leaves will curl up. The host range of pest is extensive Collect & destroy the damaged plant parts. Malathion 0.1% or Lebaycid 0.2% (2ml/lt).

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3. GUAVA MEALYBUG Ferisiana virgata Pseudococcidae: Homoptera • Of late it has become serious pest specially their nature of attack, which occurs the pest reaches pedicels, stalks and makes difficult to control. Chiefly occurs on grape branches. • They feed by sucking the juice. Infested portions are generally coated with very sticky honey dew resulting in sooty mould. Mealy bug can be washed away but not the sooty mould. Heavy infestation causes fruit drop and affects future crop also. If shoots are affected it results in malformation of leaves and twisting of vine. • During off season, crinkling of leaves and malformation of twigs due to the pest results. • Spray 3% kerosene emulsion mixed with 5 Gms of fish oil rosin soap per litre of water or DDVP 100% EC 1.5 ml with 2.5 Gms of fish oil rosin soap per lit of water or Phosalone @ 2 ml / lit of water. • Spray triazophos 2 ml+ neem oil 5 ml/1, or phosalone 35 EC 1.5 ml+ neem oil 5 ml/1. • Cryptolaemus montrouzieri grubs and adults feed on mealy bugs. Pullus sp (local) also feeds.


4. FRUIT FLY ON GUAVA (Pandu eega) Dacus (Bactrocera) divesicus • Adults and maggots attack semi – ripe fruits • Oviposition punctures on fruits • Maggots destroy and convert pulp into a bad smelling • Discoloured semi liquid mass • Adult - Brown or dark brown with hyaline wings and yellow legs • Collect and destroy fallen and infested fruits.

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Summer ploughing to expose pupa Use methyl eugenol lure trap (25/ha) to monitor and kill adults of fruit flies Prepare methyl eugenol and malathion 50 EC mixture at 1:1 ratio( take 10 ml mixture/ trap) Inseciticides: endosulfan 35 EC 0.035% or malathion 50 EC 0.05% Bait spray combining molasses or jaggery 10g/l and one of the insecticides, fenthion 100 EC 1ml/l, malathion 50 EC 2 ml/l, dimethoate 30 EC 1ml/lit, two rounds at fortnight interval before ripening of fruits Field release of parasitoids such as Opius compensates, Spalangia philippinensis, parasitoid wasp Diachasmimorpha kraussi

Nymphs and adults suck the sap from leaves Honey dew - development of sooty mould fungus Yellowing of leaves. Dropping of affected leaves. Field sanitation Removal of host plants Installation of yellow sticky traps Revised during 2011

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5. SPIRALLING WHITEFLY ON GUAVA (Jaama tella doma) Aleurodicus disperses Aleurodidae: Homoptera • Nymph - short glass like rods of wax along the sides of the body • Adult - Powdery white, active during early morning hours.


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During heavy infestation - application of imidacloprid 200SL at 0.01% or triazophos 40EC at 0.06% Spray neem oil 3% or NSKE 5% Release of predators viz., Coccinellid predator, Cryptolaemus montrouzieri Release of parasitoids viz., Encarsia haitierrsis and E.guadeloupae

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6. GUAVA FRUIT BORER (Jaama pandu toliche purugu) Dichocrosis punctiferalis • Pest of castor. • Larva - Pale greenish with pink tinge and fine hairs with dark head • Adult - Yellowish moth with black spots on the wing and body. • Caterpillar bores into young fruits • Feeds on internal contents (pulp and seeds) • Dry up and fall off in without ripening • Collect and destroy damaged fruits • Clean cultivation as weed plants serve as alternate hosts • Use light trap @ 1/ ha to monitor the activity of adults • Insecticides: malathion 50 EC 0.1% or endosulfan 35EC 0.07% two rounds, one at flower formation and next at fruit set.


Lecture 34: (INSECT PESTS OF SAPOTA & BER) 34. Major insect pests of sapota-distribution-marks of identification biology-nature and symptoms of damage and management strategies of leaf webber; Minor insect pests of sapota-nature and symptoms of damage' and management practices of parijata hairy caterpillar and mealybug; Insect pests of ber-nature and symptoms of damage and management strategies of fruit fly, fruit borer and weevil.

PESTS OF SAPOTA 1. SAPOTA LEAF WEBBER (Sapota aaku chuttu purugu, Aaaku goodu kattu purugu) Nephopteryx eugraphella Pyralidae: Lepidoptera • Major pest of sapota throughout India and found throughout year. • Adult moth is grayish, with brown or black spot on the fore wing. • The larva is pinkish in colour, brown stripes on each side of the body. • The caterpillar webs the leaves and feeds on leaves. • Also feeds on flower buds and fruits. • It also feeds on cured tobacco leaves. • Moth lays pale yellow eggs singly or in groups of 2-3 on leaves. Eggs hatch in 3-5 days and pinkish larva has close set longitudinal lines which webs and feeds on leaves. Larval period 17-32 days. Pupate within the leaf web itself. Pupal period 7-11 days. Total life history occupies 32-45 days. • Leaf web with caterpillars should be collected and destroyed. • Spray Carbaryl 0.15% concentration. • Spray phosalone 35 EC 2 ml/lit or phosphamidon 40 SL 2 ml/lit or neem seed kernel extract 5 %. • Spray application of cypermethrin 0.025 % affords protection.

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3. PARIJATA HAIRY CATERPILLAR Melanastria hyrtaca • Adults: Grayish head and thorax and whitish abdomen.Forewings are reddish brown spot ringed with white, Hind wings are white. • Larva - yellowish brown with black spots and long lateral tufts of hairs • Caterpillars feed on leaves • Field sanitation • Free from weeds and debris • Collect and destroy the egg mass • Burning the groups of larvae found on tree trunks with torches. • Spray chlorpyriphos 20EC or endosulfan 35 EC or phosalone 2 ml/l

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2. STRIPED MEALY BUG Ferrisia virgata • Adult - Female has long filaments on the posterior end of the body • Presence of white mealy mass on the terminal shoots and under surface of the leaves • Yellowing of older leaves • Collect and destroy egg masses and caterpillars • Use burning torch to kill the congregating larvae • Use light trap to attract and kill the adults • Spray methyl demeton 25 EC@ 0.05%or dimethoate 30 EC @ 0.06% • Field release of Cryptoleamus montrouzieri 20 per tree


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Spraying of cypermethrin 0.025%. Dusting carbaryl 10 D on the trunk and branches (around the tree 4 feet) Field release of chalcidid wasp, Brachymeria sp. Defoliation

4. GREEN SCALE Coccus viridis • Adult: green, flat oval soft scale • Nymph: Pale lemon yellow • Nymphs and adults suck the sap from leaves • Yellowing of leaves • Prune and destroy the infested shoots at initial stage of infestation. • Spray monocrotophos 1ml/lit or phenthoate 1ml/lit • After two weeks release 20 predator beetles viz., C. montrouzieri beetle per tree. • Encourage parasitoids viz., Aneristis sp Coccophgagus cowperi, C. bogoriensis

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2. BER FRUIT BORER (Regipandu toluchu purugu) Meridarches scyrodes • The ber fruit borer is small, dark insect brown in colour with fringed wings. • Early instar larva is light yellowish and full-grown larva is red in colour. The larva bores into the fruits and feeds on the pulp around the seeds.

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PESTS OF BER (Regupandu) • BER FRUIT borer complex consisting of ber fruit borer, Meridarches scyrodes and ber fruit flies, Carpomyia vesuviana. 1. BER FRUIT FLY (Regipandu eega) Carpomyia vesuviana Tephretidae: Diptera • The most serious pest of ber is the fruit fly, Carpomyia vesuviana, which attack the fruits at the "pea" stage. • Susceptibility generally differs by cultivar. Varieties like Gola are susceptible due to thin skin and sweet pulp. • Ber fruit flies, adult are small fly with black spots on the thorax and dark bands on the wings. • The maggots bore into the ripe fruits and feed on the pulp. • When full-grown, they come out of the fruit and drop to ground and pupate 6-15 cm below the soil. • Adult emerges from the soil.


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The fruit borer complex can be effectively managed by following methods: • Attacked fallen fruits should be collected regularly and destroyed. • Wild ber trees present around or near to the ber orchard should be removed. • Soil under the tree or near the trees should be raked to destroy the maggots and pupae present in the soil. • The fruits just before attaining the marble size, incorporate fenvelrate 0.4 per cent or chlorpyriphos 1.5 per cent dust at 40 kg per hectare to the soil under the tree or near the trees to reduce the fruit borer incidence. • Spray the crop three times, with endosulfan at 2 ml or malathion at 2 ml or fevelrate at 0.5 ml or carbaryl at 4 g or monocrotophos at 1 ml/lit of water or neem seed kernal extract (NSKE) 5 per cent; first spray at marble stage, second spray at 15 days later and third spray at fruit ripening stage, by alternate use of insecticides. For the third spray add 10 g jaggery/ litre of spray mixture. • For the control of fruit flies, use traps containing 1 ml methyl eugenol and 2 ml malathion/ litre of water. Take 100 ml of from this solution per trap and hang the traps at 10 traps per hectare.


Lecture 35: (INSECT PESTS OF BANANA & APPLE) 35. Major insect pests of banana-distribution-marks of identification biology-nature and symptoms of damage and management strategies of rhizome weevil; Minor insect pests of banana-nature and symptoms of damage and management strategies of skipper, aphids and pseudo stem weevil; Major insect pests of apple-distribution-marks of identification biology-nature and symptoms of damage and management strategies of wooly aphid and codling moth.

INSECT PESTS OF BANANA (Arati)

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Blackened mass of rotten tissue of affected rhizome which is riddled with circulate holes. Such rhizomes are cut open grubs with excreta in the tunnels may be seen. Biology: Eggs are elongated, oval, pure white and laid singly in holes made in plant tissues by female at ground level. The grubs on hatching bore through leaf sheath and riddle up to rhizome (LP: 25 days). Pupation in an oval chamber prepared just beneath Revised during 2011

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1. BANANA RHIZOME WEEVIL Cosmopolites sordidus Curculionidae: Coleoptera • Distribution in East Asia, Australia, Pacific and Indian Ocean islands, Africa, S. Africa, Brazil, West Indies. • Serious pest in some areas in India. • Adult is a medium sized, dark brown, weevil with drawn out mouth parts, measures about ½ inch in length. The elytra do not cover the whole of abdomen. • The grub is dwarf, stumpy with red head and wrinkled body. It has powerful mandibles to bore into the rhizome. • Infestation by the banana weevil begins at the base of the outermost leaf-sheath and in injured tissues at the lower part of the pseudostem. Initially the young grubs make several longitudinal tunnels in the surface tissue until they are able to penetrate to adjacent inner leaf-sheaths; they then bore into the pseudostem base and rhizome/corm, but also into the base of suckers and into roots. • Larval tunnels may run for the entire length of fallen pseudostems. • Grubs feeds by tunneling in rhizome, the tunnel is roughly circular, and increase in size with growth of grubs. • The infested rhizome becomes riddled with tunnels, which decay and whole rhizome turn into blackened mass of rotten tissue. • Infested plants have dull yellow green and floppy foliage. • Young infested suckers often wither and fail to develop. • Plants are easily blown down by mild to strong winds. • Banana plants of all ages are affected. • If fruiting takes place from affected plants, there will be few numbers of bananas, and of inferior quality very few suckers emerge from shoots of affected plants.


the surface of the rhizome below the ground level (PP: 10 days). Adult weevils can live for 6 months without food, and can live for 2 years. Management: • Use clean planting material by selecting vigorous healthy planting material. • Paring (Trimming). If clean planting material is not available the planting material should be pared (trimmed) to reduce the number of eggs and grubs. Paring and removal of outer leaf sheaths also helps to remove most weevil eggs and nematodes. • Hot water treatment. Recommendations suggest immersing clean trimmed suckers in a bath with hot water at 52 to 55°C for 15 to 27 minutes before planting. • Do not replant previously infested land while old corms remain on the ground • Avoid moving infested plant material from plantation to plantation as this will spreads banana weevils. • Practice good crop hygiene: Cut old stems after harvesting at ground level. Covering the cut rhizome with a layer of soil is said to prevent the weevil's entry and egg laying. Use mulch. Spread mulch away from banana stool leaving a clear ring of about 60 cm from the base of the stool to keep the roots from growing towards the surface, and to avoid moist conditions near the stool, which will attract banana weevils. Remove water suckers regularly Clean matts of dead leaves and plat debris Keep the plantation free of weeds at all times. • Applications of neem powder effectively controlled weevils and nematodes in on-farm trials and in farmer's fields. Application of 60 to 100 g of neem seed powder or neem cake at planting and then at four months intervals significantly diminished pest damage and increased yields. • Trapping: Disc-on-stump traps and old pseudostems can be used for trapping weevils. Disc-on-stump traps consist of corm slices placed on top of harvested plants cut at the rhizome. Old pseudostems can be cut into lengths of 20 to 60 cm and split each length, and placed on the ground near the corm bases with the cut surface downwards. Adult weevils are attracted to the cut stems or corms for shelter, to feed and to lay eggs.

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The weevils are predominantly nocturnal in habit. They often confine themselves within the pseudostem and in the decomposing tissues of harvested pseudostems. All life stages of the weevil are present throughout the year in the infested plant. \ Adults are strong fliers and in this way, move from plant to plant. The BSW has a long life span and many adults live for a year.

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2. BANANA STEM WEEVIL / BANANA PSUEDO STEM BORER Odoiporus longicollis • The banana stem weevil (BSW) or banana pseudostem borer, Odoiporus longicollis Oliver (Coleoptera: Curculionidae) is one of the most important pests of bananas and plantains. • The adult weevils are black-coloured and measure 23-39 mm. Red-coloured morphs of the BSW are also encountered in certain banana-growing areas of India.


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Adult BSW are attracted by the volatiles released by the banana plants. Infestation of the weevil normally starts in 5-month-old plants. Early symptoms of the infestation are the presence of small pinhead-sized holes on the stem, fibrous extrusions from bases of leaf petioles, adult weevils and exudation of a gummy substance from the holes on the pseudostem. During the advanced stages of infestation, the stem, when split open, exhibits extensive tunnelling both in the leaf sheath and in the true stem. Rotting occurs due to secondary infection of pathogens and a foul odour is emitted. When the true stem and peduncle are tunnelled after flowering, the fruits do not develop properly, presenting a dehydrated condition with premature ripening of the bunch itself. Stem weevil infestation interferes with the translocation of nutrients and water, retards growth and development and increases susceptibility to wind lodging, which is more commonly associated with nematode infestation. Weakening of the stem by larval tunnelling may result in breakage by wind or inability to bear the weight of the maturing bunch. It is estimated that the stem weevil causes 10-90% yield loss depending on the growth stage of the crop and management efficiency. The severity of the loss is greater when infestation occurs at the early vegetative stage (5 months old).

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Females lay yellowish white, elliptical eggs by inserting the ovipositors on the outer epidermal layer of the leaf sheath of the pseudostem (EP: 3-8 days). The emerging larvae are fleshy, yellowish white and apodous. The larvae feed on tissues of the succulent sheath by tunnelling extensively and may reach as far as the true stem. If larvae emerge during the advanced pre-flowering stage of the plant, the ascending flower bud and the peduncle inside the pseudostem can be eaten and damaged, resulting in non-emergence of the flower bud which decays inside the pseudostem. In severely infested plantations, more than 20% plants do not flower due to this reason. The depth of the tunnels made by the larvae range between 8 to 10 cm. The tunnels are widespread and may go as high as the fruit peduncle or to the lowermost collar region near the rhizome. The larvae pass through five instars. Pupate in cocoon by winding short pieces of fibrous materials of the sheath around its body. The developmental rates are highly dependent on climatic factors with the duration of the life stages longer in the winter season than in the summer. Under laboratory conditions the duration from egg to adult stage is 44 days

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3. BANANA APHIDS Pentalonia nigronervosa • The preferred host of this aphid is banana. • However, it will also infest many tropical and subtropical food and ornamental plants, including Alpinia purpurata (floral red and pink ginger), Xanthosoma (ape), cardamom, Heliconia, tomatoes, taro, Calla, Costus, kahili ginger, torch ginger, and Zingiber. • Like most aphids, the banana aphid is a phloem feeder that uses its long stylets to pierce plant tissues to suck the sap directly from the vessels. This can cause plants to become deformed; the leaves become curled and shriveled, and in some cases galls are formed on the leaves. Young plants may be killed or their growth checked if there is sufficient feeding by the banana aphid. However, direct damage by this aphid is generally negligible. • Like many other soft bodied insects, such as leafhoppers, mealybugs, and soft scales, aphids excrete honeydew. This sweet and watery excrement if fed on by bees, wasps, ants and other insects. The honeydew serves as a medium on which a sooty fungus, called sooty mold, grows. Sooty mold blackens the leaf, decreases photosynthetic activity, and decreases vigor of the host.

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Management: • Measures to curb BSW damage vary widely depending upon the type of banana production systems practiced. Large plantations resort to regular application of chemical insecticides to control the weevil. Resource-limited marginal farmers cultivating banana as a subsistence crop are unable to undertake chemical pesticide interventions on a regular basis. In this situation, cultural control strategies assume greater significance due to their ease of application and their compatibility with other methods of control. • Control of BSW is an elusive and complex problem as the life cycle of the pest may be completed within the pseudostem. • Currently stem injection of a systemic organophosphorus compound (e.g. monocrotophos) is extensively used in controlling the pest. As well as stem injection, other insecticide application methods may be used, such as swabbing along with surfactants, swabbing with mud slurry containing the candidate insecticide (25 g Beauveria bassiana), spraying and fumigation of the spaces between the leaf sheaths in the pseudostem. Fumigation of banana plants using Celphos (aluminium phosphide tablets), especially during the vegetative phase is phytotoxic and should be discouraged. • Field sanitation is imperative in the control of this pest. Dried old leaves must be removed to allow the detection of early symptoms of weevil infestation and to increase the efficacy of chemical application. Suckers should be pruned periodically and infested pseudostems must be removed from the field and destroyed. Banana stumps kept in the field after harvest must be removed and destroyed as they serve as weevil refuges and breeding sites. • Investigations made at the National Research Centre for Banana (NRCB) in Tiruchirapalli, Tamil Nadu, India have indicated that traps could be efficiently used to monitor and reduce the adult weevil population. Among the disc-on-stump and longitudinal split pseudostem traps, the disc-on-stump traps with higher exudations of plant fluids have been found to be more effective.


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Aphids vector many plant diseases that cause substantially greater losses than that caused by direct feeding injury. This is often the most damaging feature of an aphid infestation. Both wingless (apterous) and winged (alate) aphids are able to transmit viruses. Transmission is usually in a nonpersistent manner, where the virus reproduces in the plant, and aphids simply aid in transporting the virus. Banana aphid vectors bunchy top disease of bananas. Symptoms of the disease include dark green streaking of the leaves, midrib, and petioles; progressive leaf dwarfing; marginal chlorosis; and leaf curling. Fruits of diseased plants are unsaleable because they are small and distorted. In India, banana aphid vectors a mosaic virus of cardamom called "katte". The disease causes considerable losses to cardamom crops.

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4. BANANA SKIPPER CATERPILLAR Pelopidas thrax Hesperidae: Lepidoptera • The major host of the banana skipper is banana. • Other recorded hosts include bamboo, Manila hemp, coconut, and other palms besides banana. Additional hosts recorded in Hawaii are Canna, Strelitzia, and Heliconia species. • This caterpillar is a notorious pest of bananas in South and East Asia, Indonesia, the Philippine Islands and Guam. • The adult moths, like other moths belonging to the Hesperiidae family, are characterized by their large head and clubbed antennae with a recurved tip. The forewings of this moth are dark brown with three prominent translucent-yellow patches and measure about 3 inches (75 mm) in wingspan. The hindwings are dark brown. • The newly hatched larvae are grayish-green but become pale green in later larval stages (instars). The larvae are covered with short silky hairs and a white powdery substance, which is presumably a waste product of its metabolism. A strong constriction defines its dark brown-black head from its thorax. Larvae are about 2 inches long at maturity. The larval period lasts for 25 to 30 days.


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Larvae cut and roll the host leaf from the tip along the midvein, forming a tunnel, and feed within this shelter. The larvae feed from one edge of the leaf and make another roll in the leaf as fresh food is needed. The tunnel is dusted with a white waxy powder produced by the caterpillars. The rolled up leaves are often seen hanging in large numbers from the mid rib of the banana leaf. Biology: The bright yellow to orange-red eggs, that later turn yellow, are deposited singly on the lower surface of leaves. Occasionally they occur in clusters. Eggs hatch in 5 to 8 days. The newly hatched larvae are grayish-green but become pale green in later larval stages (instars). Larvae are about 2 inches long at maturity. The larval period lasts for 25 to 30 days. The light brown pupae are long and slender and also covered with the white powdery substance. Pupation occurs within the confines of the rolled host leaf. Adult moths emerge in 10 days. Control by natural enemies usually eliminates the need for chemical treatment against this pest.

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PESTS OF APPLE

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The WAA is frequently parasitized by Aphelinus mali, a tiny wasp that is native to North America. Parasitized aphids appear as black mummies in the colony. A. mali has been successfully introduced to many apple-growing areas of the world, and is providing adequate control of the WAA in several areas. Because the woolly apple aphids are somewhat protected by their waxy covering, regular spray programs may not provide adequate control. High volume applications of recommended insecticides may be necessary to penetrate the wax. Failure to control aerial infestations can result in underground infestations on susceptible rootstocks. Chemical control of root infestations is not possible; resistant rootstocks provide the only defense against underground infestations. The MallingMerton (MM) rootstock series was developed to provide resistance to WAA infestation. Revised during 2011

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1. WOOLY APPLE APHID (WAA) Eriosoma lanigerum • The woolly apple aphid (WAA), reportedly native to North America, occurs in most apple-growing areas of the world. • The WAA feeds mainly on apple, but can also be found on pear, quince, mountain ash, hawthorn, and cotoneaster. • Woolly apple aphid is a serious pest of apples, particularly young trees. Colonies form at wound sites on trunks, limbs, and twigs, where they feed on tender bark. Pruning and hail damage can create the wound sites for attack by this pest. • Its reproduction on these hosts is asexual (parthenogenetic). • Adult woolly apple aphids are wingless until a generation is produced that can migrate to a different host. Wingless adult females bearing live young are found on apple trees during the summer. This adult form is dark brown to purplish, and 1.8 mm (.07 in.) long. In aerial colonies, it has long, white, filamentous waxy secretions. In underground colonies it has a more bluish-white, rodlike secretion. Several wingless generations of WAA are produced on apple trees throughout the season. Some winged females are produced that could migrate to other apple trees or to elm, if it is present. • Cottony-white aerial colonies are found most frequently on succulent tissue, such as current season's growth, water sprouts, unhealed pruning wounds, or cankers. Heavy infestations can cause honey dew and sooty mold on the fruit, and galls on the plant parts. Underground colonies may be found throughout the year on the root system of orchard trees or nursery stock. Severe root infestations can stunt or kill young trees, but usually cause little damage to mature trees. • WAA can also transmit perennial apple canker, Pezicula malicorticis Jacks.


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Inspect apple trees carefully, and inspect them often. Signs of aphids include yellow, withered leaves, poor growth and overly shiny leaves. Spray with water, for dislodging aphids. Use recommended systemic insecticides to kill aphids. There are few insecticides specifically labeled for control of woolly apple aphid. Diazinon, Thiodan and dimethoate are recommended for control of above-ground infestations. There are no insecticides to control root infestations on bearing apple trees.

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Management: • Codling moth can be very difficult to manage, especially if the population has been allowed to build up over a season or two. In trees with low to moderate levels, codling moth can often be kept to tolerable levels by using a combination of nonchemical management methods; however, it is important to begin implementing these measures early in the season. • Where populations are high and many infested trees are nearby, insecticide applications may be necessary to bring populations down to low levels. However, to be effective, the timing of insecticide spray applications is critical and are difficult to time accurately. In most backyard situations, the best course of action may be to combine a

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2. APPLE CODLING MOTH Cydia pomonella • Serious pest of apples, pears and walnuts. • Codling moth adults are about 1/2 to 3/4 inch long with mottled gray wings that are held tentlike over their bodies. Their appearance blends well with most tree bark, making them difficult to detect. Codling moths can be distinguished from other moths by the dark, coppery brown band at the tip of their wings. • The larvae are white to light pink "worms" with a dark brown head. • On apples and pears, larvae penetrate into the fruit and tunnel to the core, leaving holes in the fruit that are filled with reddish-brown crumbly droppings called frass. If left uncontrolled, they can cause substantial damage, often infesting 20 to 90% of the fruit, depending on the variety and location. • Codling moths overwinter as full-grown larvae within thick, silken cocoons under loose scales of bark and in soil or debris around the base of the tree. The larvae pupate inside their cocoons in early spring and emerge as adult moths mid-March to early April. The moths are only active a few hours, each female deposits 30 to 70 tiny, discshaped eggs singly on fruit, nuts, leaves, or spurs. After the eggs hatch, young larvae seek out and bore into fruit or developing nuts. After completing development they leave the fruit and drop from the trees to search out pupation sites and continue the life cycle in the soil or on debris under the tree; some crawl back up the tree to pupate in bark crevices. The rate of development will vary with temperature, proceeding more rapidly in warmer weather and climates. Depending on the climate, codling moth can have two, three, and sometimes four generations per year.


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variety of the nonchemical and/or low toxicity chemical methods discussed below and accept the presence of some wormy fruit. Select less susceptible varieties Crop sanitation (removal of crop residues, pruning, removing loose bark, removal of drop fruits) reduces pest incidence. Fruit bagging also helps, but is not feasible in orchards: Excellent control can be achieved by enclosing young fruit in bags right on the tree to protect them from the codling moth. This is the only nonchemical control method that is effective enough to be used alone and in higher population situations. However, it is quite time consuming to apply the bags so this method is most manageable on smaller trees with fewer fruit. Traps (sex pheromone) also used Trunk Banding: A traditional, nonchemical method for controlling codling moth is to trap mature larvae in a cardboard band as they climb the trunk seeking a place to pupate. Banding works best on smooth-barked varieties such as Red Delicious apple, which don't provide good alternative pupation sites.


Lecture 36: (INSECT PESTS OF COCONUT) 36. Major insect pests of coconut-distribution-marks of identification biology-nature and symptoms of damage and management strategies of black headed caterpillar, rhinoceros beetle and red palm weevil; Minor insect pests of coconut-nature and symptoms of damage and management strategies of slug, termites'and mite.

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The caterpillar builds thick web inside the folding leaf lets. It lives below the web and scrape green matter. These galleries are made of silk and excreted matter. The scraped area appears whitish and dried up on the exterior. Several caterpillars making such webs in leaves to dry in severe cases resulting in poor coconut yield. Large scale drying of leaf lets and the whole plantation presents a burnout appearance from a distance, in case of severe attack. The female moth lays about 130 creamy white, scaly eggs in small batches along the underside of the leaflet, generally near the old larval galleries. Eggs hatch in about 4-5 days. Caterpillar after hatching starts feeding on the green matter of the leaf and is about 1" in length when full grown and has pale grayish green colour. Caterpillar Revised during 2011

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1. BLACK HEADED CATERPILLAR (BHC) (Kobbari Aaku Endu Purugu) (Kobbari Nalla Tala Purugu) Opisina arenosella Cryptophasidae: Lepidoptera • Opisina arenosella, is a dreaded pest of coconut. • Specific pest of coconut. • The severity of the incidence of this pest can be noticed in summer (February to June), and the affected trees present a burnt-up-look. • The pest population begins to decline with the onset of the monsoon. • It is a serious pest originally confined to coastal areas. • It has invoked into maiden areas also and has become serious in all coconut growing areas (about 40,000 ha in Andhra Pradesh). • Due to hiding nature of caterpillars, and crowns are not easily reachable, it is difficult to control by chemical sprayings. • The caterpillar feeds on green matter from lower leaf surface, remaining within silk and frass gallaries. • In severe attack all the green matter of the leaves will be eaten up. • The moth is straw to ash grey in colour, medium sized with uniform, pale whitish upper wings. • The damaging stage is the caterpillar which is slender, elongate, pinkish with black head, hence is called black headed caterpillar.


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Management: Recommendations of Dept of Horticulture, AP • Nursery: Spray Carbaryl 0.15% 3g/l or 0.05% Monocrotophos 1.4 ml/l of water. • Clip and destroy the infested material. • If the incidence is mild, release parasites by obtaining from Horticultural Research Station, Ambajipeta, Razole, Narsapur or Sompeta. • Biological Control: The team of parasites used in biological control programme attack the pest at different stages of its life history. For obtaining an effective control, scheduled releases of combination of parasites should be adopted. First release is made immediately, when the infestation is observed, second after a fortnight. Third and fourth releases are made at 30th and 45 day respectively after the 2nd release. The quantum of release of these parasites during the four periods is the same but differs between first infestation and recurrence of this pest attack and also between warm humid regions and cool dry regions. These parasites are mass multiplied on suitable alternate hosts at 4 parasite breeding stations located in the important coconut growing areas of AP viz., Rajole (East Godavari) Ambajipet (EG), Sompet (Srikakulam) and Naraspur (WG). Parasite Tampestt (Tamgestt) Egg parasite Trichogamma australicum Early larval Apanteles taragamae Mid larval Microbracon brevicornis Late larval Goniosus (Perisierola) nephantidis Prepupal Elasmus nephantidis Pupal Stomatoceros sulcatescutellum Pupal Trichospilus pupiora Pupal Tetrastichus israeli Bacterium: Serratia marcescens causes disease in larva of Nephantis serinopa • In severely infested gardens, treat the trees by root feeding of Monocrotophos at 10ml + 10ml of water per palm. Before adoption harvest all mature nuts and no harvest should be made at least for a month. • Root Feeding Technique: Expose some roots by excavating the soil at the base of the palm (No need to trace out the tip of the root). Select a matured dark brown pencil thick root near the base and cut without damaging the cut end of the root. Take a small (15 x 10 cm) polyethene cover, pour monocrotophos @ 10 ml/palm diluted with an

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forms galleries on the under surface of leaves folding leaf lets and binding the two holes of the leaf lets together and feeds within. It charges into a brownish pupa inside the sand gallery larval period lasts for about 40 days. Adult emerges out after 12-14 days. Total life history occupies about 45-60 days.


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2. RHINOCEROS BEETLE (Kobbari Kommu Purugu) Oryctes rhinoceros Scarabaeidae: Coleoptera • It is a common pest and has a very wide distribution. • It has been reported from all regions where coconut is grown. • Other host plants: Palmyra, Date palm, Pineapple, sugarcane etc. • The adult beetle is stout, black or reddish black about 1½ -2" length. The dorsal side of body is smooth and shinning black while the ventral side is brownish and hairy. On the face of beetle has a pointed horn which is longer in the males. The insect is therefore called the rhinoceros beetle. The beetle can fly long distances. • The freshly hatched grub is about ¼ and has only three pairs of thoracic legs. The full grown grub is about 3½ -4" head is brownish and the body is dirty white except the tail

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equal quantity of water. Adjust the cover so that the cut end of the root is completely immersed in the solution. The solution will be absorbed by the palm within 24 hours. If it is not absorbed by the palm within this time, change the root on the following day of treatment and arrange as useful with the same solution. The peat will be controlled within 7 to 10 days after treatment. 10ml monocrotophos is the dose recommended for 15ft height palm, and if the palm height is >15ft, 15 ml is recommended. Recommendations of CPCRI, Kasargod, Kerala • Biological suppression of the leaf eating caterpillars is the most effective way to manage this serious menace. The pest can be managed well by the release of parasites such as Elasmus nephantidis, Goniozus nephantidis, Brachymeria nosatoi and Xanthopimpla punctata in the infested coconut groves," Central Plantation Crops Research Institute (CPCRI), Kasaragod, Kerala. • When the infestation is severe, the affected lower fronds should be cut and burnt. • The under surface of the remaining leaves should be drenched thoroughly using a spray fluid of any eco-friendly, botanical insecticides. • The natural enemies of the pest should then be released at least three weeks after the spraying. • The scientists at CPCRI have standardised the techniques for the mass culture of the larval and pre-pupal parasitoids. The larval parasitoid, Apanteles taragamae should be released from the 10th to 25th days of the adults' emergence and a pair of newly emerged male and female should be released. The progeny of the parasitoids will be female biased. The parasitized larvae should be placed near the fresh leaflet before 12 hours for effective action and development. • The other parasitoid, Goniozus nephantidis, should be released between the 10th and 14th days after adult emergence. One or two mated females of 2 to 3 days old should be released. This parasitoid stings and paralyses the third instar of the host larvae, but the laying of eggs occurs from the fourth and later instars. • The pre-pupal parasitoids, Elasmus nephantidis, should be released on the eleventh day of adult emergence. Two or three mated females (1 to 2 days old) should be released. This parasitoid is highly host specific and stage specific. The other pre-pupal parasitoid, Brachymeria nosatoi, should be released between the 12th and 20th days of adult emergence. A mixture of both female and male parasitoids numbering between 30 and 50 should be released for effective action. • Another of the pre-pupal parasitoid, Xanthopimpla punctata, is found to be effective in checking the population of the black-headed caterpillar. One or two of the mated females (4 to 5 days old) should be released on the 10th to 12th days of adult emergence to get the desired results.


end which is dark. The body segments are wrinkled. The grub is always curled up ventrally.

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The adult causes harm by boring into the unopened tender fronds biting the fibrous portions, chewing the juice from the fibrous material and throwing it out as a dry fibrous mass. This mass is commonly seen in the furrow made by the beetle and its presence indicates the pest activity. Grubs are harmless. The injury caused by the adult to young fronds is clearly seen as a series of holes on the fronds when they open out and this is the characteristic outward indication of an infested tree. When the growing point is out, tree suffers seriously and in some cases dies off. The damage caused by the beetle is more serious in young trees. The beetle breeds in decaying organic substances. Early stages of the pest generally are passed in manure pits and decomposing vegetable matter, chiefly dead palm trunks. The female adult lays the oval white seed like eggs singly in manure pits to a depth of 5-15 cm. A female may lay up to 140-150 eggs which hatch in 8-18 days. Grub stage lasts for 99-182 days. The grubs feed on manure, and do not cause any harm to the crops. The pupation takes place inside the earthen cocoon about 6-4" feet deep. The pupation period is about 10-25 days. On emerging from pupa, the beetle flies away to the nearest palm trees and starts its activity. Laying of eggs starts after 10-16 days after emergence. The adult lives for more than 200 days under favorable conditions (the total life history takes about 6 months and about a year in Bihar). Adult can survive for a month without food. Beetles are attracted to light in night times.

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Management • Hook out / extract the beetle from the attacked palms using barbed iron hook / wire. • As a prophylactic measure, fill up the top most three leaf axils with Carbaryl 8G (25g) + fine sand (200g) thrice in April, September and December. • Place 10.5g naphthalene balls in the leaf axils and cover it with fine sand. To be practiced once in 45 days. • Spraying 0.01% Carbaryl (50WP) in the breeding sites of the beetle helps destroy the larva. • Biological control using the virus Baculovirus oryctus (release 10-15 virus infected beetles in 1 ha) • Green muscardine fungus, Metarrizhium anisopliae (spray 250ml Metarrizhium culture + 750ml water in manure pits and other breeding sites of the beetle) • Practice clean cultivation: Manure pits may be periodically examined and destroy the early stages of the pest viz., egg grubs and pupae. • Crownless trunks and dead trees should be cut and dried, otherwise beetle will breed in them. • Poisoned bait and breeding traps are affectively used. The breeding traps are made out of rotting mustard or (rape cake or) castor cake or dung. Providing the bait base with carbaryl 0.1% concentration gives good control.

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Grubs feed soft tissues in the trunk of 2-10 years old Palms. Exudation of brownish fluid and protruding of chewed fiber can be seen from the holes present on the truck. Causes very severe damage, especially when a large number of grubs bore into the soft growing parts. In early stage, the symptoms of damage are not detectable but later the trees show small holes on crown. Drying of leaves, Protruding chewed fibers, Oozing of brownish sap are commonly observed in the weevil affected coconut palms. The weevil is attracted to the trees by the smell of the palm juice which flows as a result of the wounds caused by man or the agents. The dead palms also attract the beetles.

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3. RED PALM WEEVIL (Kobbari Erra Mukku Purugu) Rhynchophorus ferrugineus Curculionidae : Coleoptera • Unlike rhinoceros beetle the adult weevil is incapable of doing any direct damage to the palm unlike rhinoceros beetle. • The damage is caused by the grubs, which live and feed within the palm trunk. • The grub feed on soft tissue of trees and often cause very severe damage, especially when a large number of them bore into the soft growing parts. • All palms including coconut, the data palm and the sage palm (Metroxylon spp).


Presence of holes on the stem, oozing out of viscous brown fluid and extrusion of chewed up fibres through the hole. • Sometimes the gnawing sound produced by the feeding grubs will be audible. • In the advanced stage of infestation yellowing of the inner whorl of leaves occur. • The crown falls down or dries up later when palm is dead. Management: • Practice clean cultivation by cutting and removing palms already damaged and the decaying stumps in the garden. • Damaged palms should be split open and the different stages of pest inside burned off. • Avoid injury to the trunk as the pest lay eggs in these wounds. • Wounds if any, should be pasted with a mixture of carbaryl / Thiodan and soil. • While cutting leaves, retain at least 1m of petiole. • Use pheromone trap for attracting weevils and kill the collected ones. • If rhinoceros beetle attack is prevalent, follow the recommended measures. Use fungicides if leafrot / bud rot is noticed as the weevil lays eggs in such palms. • Inject attacked palms with 0.1% Endosulfan (3ml / litre water) or 1% Carbaryl (20gm/litre). • Plug the holes in damaged region and pour the insecticide suspension into a slanting hole made above the damaged portion using a funnel. Then plug this hole also. If needed repeat after one week. •

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4. COCONUT SLUG CATERPILLAR Macroplectra neraria Cochlidiidae: Lepidoptera • It occurs in a sporadic form. • Especially on the west coast of India. • From south India: More common in the Godavari district of Andhra Pradesh. • The caterpillar feed on leaves, buds, flowers, shoots and developing fruits are attacked.


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Natural parasitation occurs with larval and pupal parasites. Bacterial and fungal (fungus–Aspergillus sp). Infections on larvae and pupae are commonly noticed in rainy seasons. Spray carbaryl / monocrotophos.

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5. ERIOPHID MITE (Kobbari Nalli) Aceria guerreronis Acarina:Eriophyidae • The Eriophid Mite (Aceria guerreronis (Keifer) (Acarina: Eriophyidae) which was a minor pest of coconut in India has become a major pest on coconut recently. • The attack of this mite was first recorded in 1965 in guerrero, Mexico. Later it was reported from Ivory cost, Brazil, Costa Rica etc. The first Indian report of this pest is from Ernakulam District of Kerala during 1998. The sporadic occurrence of this pest is reported from almost all the 14 districts of Kerala, Tamil Nadu, Karnataka, Andhra Pradesh and Kalpeni Island of Lakshadweep. As per the recent survey conducted in Kerala (13th -18th December 1999) about 589 lakh bearing palms are affected. • It is an exotic pest, entered into India from Sri Lanka. • This accounts for about 42% of the total yielding palm population and the estimated crop loss is in the tune of 21.8%. • A roving team to study the intensity of infestation has identified its occurrence from all the South Indian States and Union Territory of Lakshadweep. • The mites are very minute in size and are not visible by naked eye. The size of this measures to 200-250 microns in length and 20-30 microns in width. The life cycle of this mite is completed in 10-12 days. • Mites remain underneath the periyanth (cap) and cause injury by feeding on the soft paranchymatic tissues. • Though the mites are microscopic their damage is enormous and hundreds of mites could be seen in each infested button and tender nut. • Visible symptoms are brown discoloration noticed in patches of the husk. • In case of severe attack the button sheds, resulting in very poor setting percentage. • In other cases the nuts are deformed and undersized with poor development of kernel and husk. • In severe cases, oil percentage also reduced. • The mites spread through wind and its multiplication is at a high rate. Though this pest was noticed only in a limited area during 1998 it has become a major pest of coconut in India.


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6. WHITE GRUB Leucopholis coneophora Mololonthinae:Coleoptera • The white grubs are mostly found in sandy loam tracts of Kerala and Karnataka. • It damages the roots. • In seedling, it tunnels in to the bole and collar region. • It has an annual life cycle with a grub period of 8 months. • Peak grub population is observed from Sept. to Oct. • Adult beetles emerge out of the soil after pre- monsoon showers in May-June during sunset hours. • Plouging and digging of soil during pre and post monsoon period will expose the insect for predation. • Collection and destruction of the adult beetles during May-June. • Setting up light traps to attract adult beetles.

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Management: • Being a micro pest inhabiting under the periyanth, the control measures at field level are not easy. However by adopting the following integrated plant protection measurers the mite population could be reduced considerably. • Adoption of phytosanitary measures in coconut gardens such as cleaning the crown of the palm, keeping the plantation clean and burning of all immature nuts fallen due to mite infestation. • Spraying bio-pesticides on the bunches a) 2% neem oil - garlic emulsion (20ml neem oil + 20g garlic + 5g bar soap in 1 litre water). Emulsion has to be prepared on the same day of application itself. b) Other neem based pesticides at 0.004% (Azadirachtin). If the pesticide formulation contains 1% Azadirachtin, 4ml has to be used in 1 litre water. Wherever spraying is difficult root feeding may be resorted to with Azadirachtin 5% formulation (7.5ml+7.5ml water) or Azadirachtin 1% formulation (10ml + 10ml water). • Spraying has to be done 3 times a year - December-February, April-June and September-October. While spraying, ensure that the spray fluid falls over the perianth region especially on button and tender nuts. On an average 1-1.5 litre spray fluid is required per palm. Care should be taken to harvest mature bunches before spraying. • Following palm health care practices also may be adopted. a) Recycling of biomass generated within the coconut system by vermi compost method or by using lignin degrading fungus. b) Raising of green manure crops in the coconut basins (like sunhemp, cowpea, calapagonium etc.) and incorporation into the soil in the basin itself, these act as mulch during summer and slowly decompose and provide nutrients when incorporated to soil. c) Application of recommended dosages of fertilizers, in two split doses, as per the package of practices prevailing in the respective states. d) Recommended level of irrigation during summer months i.e. 250-500 litres of water per tree per week (based on evapotranspiration in the given area). e) Soil moisture conservation by following methods: Burial of coconut husk in the basin, Mulching the basins (2m radius) with coconut leaves/green manure / green leaf manure, Mulching with coir pith wherever available (2m radius). • Spray dicofol / wettable sulphur, if possible • Follow root feeding technique with monocrotophos


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Application of phorate 10G @ 100g per palm should be mixed and raked in the top 15cm soil in May-June and Sept.-Oct. is recommended in coastal and Malanad areas. Irrigation is necessary after the pesticide application.

7. TERMITES Odontotermis obesus • It is estimated that nearly 20% of the coconut seedlings are damaged by termites particularly in laterite soil. • Adoption of field sanitation by disposal of organic matter in nursery soil and covering germinating nuts with a layer of river sand. • Drench the nursery with 0.05% chlorpyriphos twice at 20-25 days interval Swab the affected trunk with the same chemical.

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8. RATS • Attack tender nuts resulting in immature nut fall. • Entry of rats on to the trunk can be prevented by fixing mechanical barriers upto 2m height from ground level using 40cm sized G.I. sheets. • Use rat traps. • Poison baiting with zinc phosphide or warfarin. • Fumigate the hiding places using Aluminium phosphide tablets. • Place wax blocks containing the poison Bromodioline @ 30 blocks per ha (each weighing 10g) on 5 palms. Repeat after 12 days. Practice this two times for reducing rat population.


Lecture 37: (INSECT PESTS OF TOBACCO)

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Integrated Insect Pest Management in Tobacco, as suggested by DAC, GOI • Mix endosulfan 4a% dust @ 40 gm per 10 sq. m bed in the top soil or drench with chlorpyrifos 20% EC. @ 2 ml/liter of water one day before sowing in the nursery to prevent damage to seeds and tiny seedlings from soil pests like ants, mole crickets, earthworms, etc. • The pests commonly noticed in the nursery are (i) caterpillars (ii) Stem-borer (iii) Grasshoppers and (iv) Whitefly. Caterpillars and Cutworms • Spodoptera Litura F. commonly known as tobacco caterpillar is the worst pest in tobacco nurseries. The well grown caterpillars are grey or dark brown with v shaped white mark on the front portion of the black head. They feed voraciously along the veins of leaves and also cut the stems of small and tender seedlings. Hence they are also known as cutworms. They can be controlled by (i) deep ploughing of nursery area during April-May which will expose pupae to high temperature and destroy them (ii) sowing castor around tobacco nursery 15 days before sowing of tobacco so that castor puts up sufficient foliage by the time Spodoptera infestation builds up. (The castor seedlings attract female moths of Spodoptera for egg laying) (iii)spraying of 1 percent Neem seed Kernel suspension (NSKS) in water on 3 weeks old seedlings and 2% NSKS on 4 weeks old seedlings. NSKS may be prepared by dipping a muslin bag containing 100 gm of neem seed kernel powder in a bucket containing 10 litres of waters and squeezing the bag for 15 minutes to get a light brownish liquid. The suspension can be directly sprayed on tobacco seedlings. (The necessity for spraying can be decided by fixing pheromone traps. Spraying can be avoided if the catch of male moths is less than 5 per trap). For preparing 2% NSKS of 10 litres, 200 gm of neem seed kernel powder is to be taken and prepared as above. Use 50 litres of 1% NSKS on 3 weeks old seedlings and 60 litres of 2% NSKS on 4 weeks old seedlings. (iv) If the catch of male Spodoptera moths to continue to be more than 5 per trap beyond 4 weeks and the number of seedlings damaged by Spodoptera exceeds 6 per sq. m. area spray one of the following insecticides: Chlorpyrifos 20% E.C. @ 25 ml. in 10 litres of water, Quinalphos 25% E.C. @ 25 ml. in 10 litres of water, Monocrotophos 36% W.S.C. @ 15 ml. in 10 litres of water. • Stem borer: The stem-borer is the larva of a tiny brown moth called Scrobipalpa (Gnorimoschema) heliopa Low. The tiny caterpillars bore inside the stem and mid ribs and feed on internal tissues. As a result, swelling appears where the borer stays. It causes stunting and unusual branching of the seedlings. At the planted crop is also affected by this pest. (i) suffocated seedlings should be removed and destroyed. (ii) Spray Quinalphos 25% E.C. at 0.05% (20 ml in 10 litres of water) at 30 and 40 days after germination. Final spray should be given before pulling out seedling. (iii)In planted crop spray above insecticide at 20 and 30 days after planting. (iv) After completion of harvesting the stem borer affected plants should be uprooted and burnt to prevent carryover of the pest to the next season. • Grasshoppers: These are green or brown jumping insects. they feed on leaves making circular holes.

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37. Insect pests'of tobacco-distribution-marks of identification-biology nature and symptoms of damage and management strategies of tobacco caterpillar, aphids and whiteflies.


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(i) cultural practices like keeping the nursery area free of weeds and grass helps to keep away the grass-hoppers. (ii) Spray the surrounding vegetation with endosulfan 35% E.C. @ 15 ml. or chlorpyrifos 20% E.C. @ 25 ml. in 10 litres of water or dust the area with endosulfan 4% dust @ grams per 10 sq. m. area. Whitefly. (Bemisia tabaci Gennadius): White flies are small fly like insects seen on the underside of leaves. They will fly immediately when the plant is disturbed. The adult fly sucks the sap from leaves and transmits the leaf curl virus diseases from infected to healthy seedlings. Normally this pest can be controlled by spraying any of the pesticides recommended for control of S. Litura F. Control measures for endemic zones. (i) Remove alternate weed hosts around nursery area and destroy (ii) Install yellow-sticky traps (20 cm x 15 cm size galvanized iron sheet) coated with castor oil @ 5 per acre. (iii)If the population of white fly is heavy, give the following spray schedule of insecticides at weekly interval commencing from 4 weeks after germination. 1st spray-Chlorpyrifos 20% E.C. @ 25 ml in 10 litres of water 2nd spray-Monocrotophos 36% WSC. @ 15 ml in 10 litres of water 3rd spray -Acephate 25% S.P. @ 10 gm in 10 litres of water 4th spray -Demeton-s-mehtyl 25% E.C. @ 15 ml in 10 litres of water.


Lecture 38: (INSECT PESTS OF COFFEE & TEA) 38. Major "insect pest of coffee-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of white borer; Minor insect pests of coffee-nature and symptoms of damage and management strategies of red borer and green scales; Major insect pests of tea-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of tea mosquito bug; Minor pests of tea-nature and symptoms of damage and management strategies of thrips, red spider mite, pink mite, purple mite and scarlet mite.

PESTS OF COFFEE

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Characteristic feeding damage caused by adult and grub is presence of small round hole in the navel region of developed berry, endosperm is damaged by making small galleries near the main tunnel, female adult tunnel in berry, grubs feed on bean, resulting in the plant dropping tender berries. The female coffee berry borer bores into young as well as ripe berries generally through the navel (tip) region. But tunneling and egg laying are only possible in berries where the endosperm has hardened. The female drills the berry through the central disc, although it can enter through the side walls if the fruit is dry. On an average around fifty eggs are laid in the tunnel within a mature bean. The eggs hatch in 5-9 days. The grubs feed on the beans, making small tunnels. Complete development from egg to adult takes place in about thirty days. The fertilized female leaves the parent tunnel and bores into a fresh fruit for oviposition (egg laying). The average longevity of the female is 156 days, which is sufficient to enable the pest to carry over from one season’s crop to the next, under Indian conditions. Thirty to eighty per cent of the fruits may be attacked if the infestation is severe, resulting in heavy crop loss. Generally only one of the beans in a berry is affected, though damage to both the beans is observed in case of severe infestation. Broca traps used to attract beetles. Wherever arabica is interplanted with robusta or is grown as a separate plot in close proximity with robusta, the berry borer is in an advantageous position as the coffee fruits of the right maturity are available for a longer period. For example, arabica berries mature early and the berry borers start a new life cycle on them as soon as the endosperm hardens. By the time a new generation emerges in about thirty days time, Revised during 2011

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1. COFFEE BERRY BORER (Kaafi kaaya totuchu purugu) Hypothenemus hampei Scolytidae:Coleoptera • The coffee berry borer, Hypothenemus hampei, is a small beetle native to Africa. It is recognized as the most harmful pest to coffee crops worldwide. • The delay in harvest results in more generations of the borer multiplying in the field. • The availability of the fruits on the field for a longer period permitted the borers to continue breeding and spread to more areas.


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the endosperm in the robusta berries also would have developed to the consistency preferred by the borers to make tunnels and multiply. In such plots or areas, it is preferable not to delay the harvest. If harvest is delayed, the berry borer can complete more generations on the fruits and the effect on the crop, particularly robusta coffee, would be severe. In Arabica plots close to robusta, berry borer traps @ 27 per acre (40 feet spacing) may be installed after harvest so that migration to robusta can be minimized. To prevent the escape of beetles back to the estate, the coffee harvested from infested blocks may be dipped, along with the gunny bag, in boiling water for two minutes and then taken to the drying yard/pulper. Alternatively, polythene sheets smeared with a vegetable oil may be placed above the coffee while drying, for three to four days, and the trapped beetles destroyed. Berry borer traps may also be installed around the drying yard while coffee is being dried.

2. COFFEE WHITE STEM BORER (Kaafi kamdam totuchu tella purugu) Xylotrechus quadripes Cerambycidae: Coleoptera • The coffee white stemborer, Xylotrechus quadripes, occurs in India, Sri Lanka, China and Vietnam. • One of the important pests of coffee in India. • Stemborers are the most important pests of arabica coffee in Asia and Africa. • The larvae bore into the stem causing death of young plants. Grubs burrow into the stem for 8-9 months and cause wilting of branches, occasionally leading to death of bushes. Older plants may survive but yield is drastically reduced and susceptibility to diseases and termites greatly increased. • Adult: Black elongate with grey pubescence on head, thorax and elytra , white cross bands on elytra; Grub: White or yellowish, anterior end broader and tapering towards tail end.

3. COFFEE GREEN SCALES Coccus viridis Coccidae: Hemiptera • Green coffee scale has an extensive host list spanning 57 plant families. Some common host plants for it include: avocado, camellia, citrus, coconut, coffee, fig, frangipani, gardenia, guava, hibiscus, litchi, mango, mangosteen, oleander and pineapple.

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Biology: Eggs (50-100), laid in the crevices of the bark on stem, larvae hatch in 8-10 days and feed for 8-9 months and pupates in stem itself and emerges as adult after 2530 days, adult emerge in large numbers at two distinct period from April to May and October to November. Control methods are limited, and infested trees should be removed and destroyed to prevent infestation of surrounding trees.

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The adult scales are small insects, about 3 to 4 mm in length, which can be seen by the naked eye. Unlike most other soft scale species, the green coffee scale has well developed legs which enable it to move about the host plant. The nymphs, which are also known as crawlers, develop through multiple instars (stages). They are ovalshaped and mobile. Green coffee scale activity usually occurs on the underside of the leaf and twigs. However, when infestation levels are high, the scale can be found on the upper leaf surface and on fruit. A useful indicator of activity is the blackening of the upper leaf surface with sooty mould. A severe infestation of the scale can reduce photosynthesis in the leaves which reduces the vigour and productivity of the host tree. Sooty mould, also formed on the fruit, can increase production costs.

PESTS OF TEA

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Eggs cylindrical slightly curved with two filamentous structures at one end. Eggs remain inserted in young leaves and buds with filamentous structures projected from the surface. First instar nymph, tiny, brownish head, legs and abdomen. Eyes pink, antenna longer than body and labium extending up to half the abdomen. Second instar, have most of the body parts orange to brownish, drumstick-like process just appear. Third instar has reddish green body. In fourth instar, body turns greenish yellow. Fifth instar reddish green having a green abdomen about 5 mm long. Drumstick process and wing pads

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1. TEA MOSQUITO BUG Helopeltis theivora Miridae: Heteroptera • Adults black usually with greenish abdomen. Antennae very long and black but with pale basal segment. Head and wings black. A small drumstick like process stands vertically on the upper side. Eyes prominent. Adults are quick but not strong flyers. Females bigger than males having curved ovipositor, males are lighter in colour than females.


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2. TEA GREEN LEAF HOPPER Empoasca flavescens Cicadellidae : Homoptera • The adult leafhopper is 2 - 4 mm long with a green colour. The wings are transparent and green. Leafhopper nymphs have no wings, but advanced ones have wing buds. A newly hatched nymph with a transparent white colour. The older nymphal stages (instars) get the green colour. The last instar is about 2 mm long. Legs specially developed for hoping. • Eggs are laid by inserting in the tissue of new tea buds and shoot, particularly in the internode. In one bud up to 7 eggs are laid. One female can produce maximum 100 eggs during her lifetime. Depending on the temperature, the eggs will hatch after 5-10 days, producing nymphs. There are five nymph stages. The total nymphal development period is 7 - 16 days being faster in warm weather condition. So, it takes from 12 - 30 days for leafhoppers to complete a generation. There can be as many as 10 generations in a year. The life span of the adults is 14 - 21 days; females in general live longer than males. • Both nymphs and adult leafhoppers use their needle-like mouthparts to suck sap from the leaves. Leafhoppers do not like direct sunlight and therefore prefer to stay on the underside of the leaves. When they walk, they move sideways. When the plant is disturbed, they jump very quickly and dodgingly dart away. • Nymphs are more damaging than adults. Due to intensive sucking the affected leaves curl downwards; the margins become curved, then turn brown and gradually dry up. This typical symptom is called “Rim Blight”. • The midrib and veins of affected leaves also show somewhat brownish discoloration. Photosynthetic activities is drastically reduced due to loss of chlorophyll, this coupled with imbalance in growth hormones results in stunted plant growth. Hoppers feeding marks appear small yellow spots. Under dry conditions, the upper part of leaves dry out. The less seriously affected leaves may develop a purple colour.

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well developed. The latter extending up to half the abdominal length. Nymphal development period varies from 20-30 days. The H. theivora occurs widely in the foothills and the plains mainly attacking tea and weeds specially Mikania growing in tea areas. Nymphs and adults are more visible in early and late hours of the day and take shelter under tea leaves specially in the lower frame during day time or when disturbed. One individual usually completes its life cycle on a single bush. Damage of tea shoots and young leaves occurs due to inserting of eggs which is highest in the bud region followed by shoot and the young leaves and their petioles. Severe damage occurs due to intensive feeding by all the stages and due to chemical reaction within the leaf resulting from feeding punctures and extra-oral digestion. The feeding spots develop watermarked area, which turn circular and pale green and subsequently dark brown within hours of feeding. The circular area later becomes dark brown and when dried up hole develops. The toxic reaction of feeding often results in curling and deformities of leaves. As a consequence, the shoot is retarded. In recent time chemical control at recommended doses is becoming increasingly difficult. Helopeltis are predated by Oxyopes sheweta (Lynx spider). Spray endosulfan (or) phosalone (or) monocrotophos 2ml / lit of water for better control.


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3. THRIPS Mycterothrips setiventris Scirtothrips dorsalis Thripidae : Thysanoptera • The adult Mycterothrips setiventris (common thrips) is just barely visible with the unaided eye. They range in colour from pale brownish-red to pale green-yellow. Wings when present are very small and transparent, and are composed of many small light hairs. Nymphs look like small adults with no wings. Eggs are very small. Thrips walk slowly, although they can fly from plant to plant quickly. Scirtothrips dorsalis is known as Assam thrips. These are smaller in size than M. setiventris and are active in the bud and first few tea leaves. • The eggs are inserted singly into the leaf tissue, usually next to a vein. There are two active nymphal stages that feed by sucking plant sap. The pre-pupal stage is not very active and does not feed. The pupa is often found in fallen leaves under the tree or in the soil, but sometimes in old and dead leaves, on bushes, cracks, or moss and lichens on the tea trunk. Adults emerge from the pupae. Duration of each stage depends very much on the temperature: egg 8-16 days, active nymph stages 8-16 days, pre-pupa 1-4 days, and pupa 4-7 days. Thus, M. setiventris can complete a generation (from eggs to new adults ready to lay eggs) in 21 to 42 days with the adult longevity of 5 to 19 days. S. dorsalis can complete its life cycle in 13 to 17 days. • Thrips, after hatching from the egg start sucking sap. Often the attack begins right inside the rolled-up bud. The affected buds grow small, crisp, easy to break and often when the damaged bud unfolds, the leaves have a brown line of dry scars (like cork) along either side of the main rib (parallel to the main vein). • Thrips also feed on the youngest open leaves. The sucking marks often are made one after one, forming thin pale lines on the Underside of the leaf. These lines are parallel to the main vein. Leaves that have a lot of this type of damage become dotted with tiny pale patches, and are often described as “silvered”. After being damaged, leaves become thicker and harder than the normal ones, duller with darker green colour, and often puckered or deformed. Thrips also feed on the surface of stems, but only near the tip of a young shoot. This stem feeding causes rough, brown dots or patches on the surface of the stem. Revised during 2011

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Newly planted and young teas suffer worst when attacked by leafhoppers with drying out of new shoots and stunted growth. If feeding is severe and prolonged, newly planted tea plants could even die. Full-grown tea plants are able to considerable tolerate leafhopper feeding. However, high populations of leafhoppers can reduce the yield and quality of the tea. Ladybeetles, Neuropterans, praying mantids feed on leafhoppers. All these natural enemies prey on both young and adult hoppers, but they seem to prefer the nymphs. Controlling leafhoppers is done by good cultivation practices. If pruning and plucking are not carried out in time the tea plants will grow weak and many leafhopper eggs will hatch in the field. Good fertilizer management is also important, making sure that besides nitrogen (urea) all necessary elements are given. The frequency of plucking plays an important role in limiting leafhopper populations. When plucking is done at short intervals, suitable sites for egg laying are reduced. Also, with the harvested buds many eggs are destroyed. Tea growing under shade trees tends to have less leafhoppers problem. Mulching also helps to increase humidity and therefore reduce leafhopper populations.

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4. Tea Mites a) Red spider mite, b) Scarlet mite, c) Purple mite, d) Pink mite (or) Orange mite, e) Yellow mite,

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Oligonychus coffeae Brevipalpus californicus Calacarus carinatus (Pest of South India) Acaphylla theae Polyphagotarsonemus latus

Red spider mite, Oligonychus coffeae Tetranychidae: Acarina A red spider mite lays eggs adjacent to mid rib and veins. Eggs are laid one at a time ranging from 4 to 6 per day. Female oviposits over a month. The red spider mite completes several generations in a year and females have the capacity to reproduce parthenogenetically i.e. without fertilization of eggs, producing male progeny. A female may live upto a month. Red spider mites spin silken net over their colonies so that they can move underneath these webs protected from weather vagaries. They move from one bush to the other by the silken thread, wind and by sticking to the body of animals and people who pass by the bush. Increase in red spider mite population is mainly related to the dry season and rise in temperature during spring and early summer in North East India. The mites attack the upper surface of mature leaves starting from the midrib and vein areas and gradually spread to the whole of the leaf. The feeding causes the leaf to turn coppery-red coloured. Mites leave their cast skin and empty eggs as white spakes on the leaf surface. Heavy infestation leads to dropping of the leaf. Factors like drought, unprunned tea, sunny days, unsmooth leaf surface texture and dust accumulation allows easy proliferation of the mite population. Further the increase in mite population may be influenced by organic manuring, poor drainage and may be influenced by the weeds acting as alternate host in the plantation areas. Natural enemies of red spider mites that ranges from Coccinellid to Neuropteran. Predatory mite Agistemus sp. Rove beetles also consume most of the life stages of red spider mite. Revised during 2011

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Lady beetle, small black spider, ant, carabid beetle, predatory bugs and web spider are natural enemies of thrips. They can kill both nymph and adult thrips. In other Asian countries, lacewing larvae (like Chrysopa) and predatory mites are important predators. Also, there are several kinds of tiny parasitoid wasps that attack the eggs (families Eulophidae and Scelionidae). The application of pesticides, especially those with wider range of functional effectiveness, will reduce very much the population of these natural enemies. Thrips are often a problem in old, stunted and dry tea fields. Therefore, good tending and management practices (including balanced fertilization) will reduce the damage to tea plants. Watering also helps plants to recover. Thrips attacks seldom last more than a few weeks, and the plants often grow out of the damage quite quickly if well tended. Preservation of natural enemies is very important to limit the population of thrips. Reduced use of insecticides and avoidance of broad-spectrum insecticides help conserving the natural enemies. Thrips are favoured by dry and hot weather conditions. Planting shade trees is one of the best ways to reduce thrips populations. Mulching also helps to increase humidity in the field. Because thrips feed mostly on buds frequent plucking of youngest leaves can greatly reduce the number of thrips. Spray dimethoate 30 EC (or) chlorpyriphos 20 EC 2 ml/lit.

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Spray dicofol 18EC 2 ml/lit or ethion 50 EC 2 ml/lit or monocrotophos 1ml/lit Application of wettable sulphur 80 WP 2g/lit using hand operated sprayer.

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Lecture 39: (INSECT PESTS OF TURMERIC & GINGER) 39. Major insect pests of turmeric and ginger-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of turmeric rhizome, fly; Minor insect pests of turmeric and ginger-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of lacewing bug.

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1. RHIZOME FLY (Pasupu Dumpa Eeega) Mimegralla coerrulelfrons Micropisidae: Diptera • Rhizome fly is becoming a serious menace to the cultivation of the turmeric and ginger crops in recent years in Maharashtra State. • The flies are fairly large with slender body and long legs. The body is black in colour and wings are transparent with ashy spots. The wing expansion of flies varies from 13 to 15mm. The eggs are small, white, cigar shaped, tapering at either side. • The full grown larva is creamy white in colour, apodous. • Host plants: Turmeric and ginger • The maggots feed on the rhizome as a result of which yellowing of plants and rotting of rhizomes takes place. • Dead hearts are formed due to primary injury of the maggots which bore the shoots in the beginning and finally reach rhizomes, for feeding. • These maggots are suspected to cause complete damage to the rhizomes by feeding and facilitate for the invasion of the fungus Pythium sp resulting in rotting of rhizome.


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Fliers are noticed in the fields in the months of August and September. Female fliers lay eggs singly or in clusters of 6-10 near the base of the plants under small lumps of soil, in cracks and on the surface or soil. The incubation period lasts for 2-5 days. The larval period lasts for 13.18 days. The full-grown maggots pupate into rotten rhizomes. The pupal period lasts for 110-15 days. The pupal period lasts for 10-15 days. The total period of life cycle is about 4 weeks. Preventive measures like destruction of stray plants in off season Selection of healthy rhizome for planting Removal and destruction of rotting rhizomes along with the maggots from the field after the harvest of the crop may help to check the breeding of the pest. Spraying with 0.05% fenitrothion of monocrotophos of 0.02% diazinon was found to be effective.

2. LACE WING BUG Stephanitis typicus Tingidae: Hemiptera • Also pest of banana. • Nymphs – are yellow colour, occur in under surface • Adult – yellow colour with minute fringed wings, seen in under surface of leaves

Colonies of nymphs and adults suck the sap from upper surface of leaves and cause yellowing of leaves in patches, dryup and drop off. • Nymph and adult suck the plant sap and inject toxic saliva in the tissue • Leaves with greyish yellow spots, stunted growth. • Collect and destroy the damaged leaves, flowers and fruits along with life stages • Spraying with dimethoate 30 EC - 850 ml/ha or phosphamidon 85 WSC - 300 ml/ha • Spray methyl demeton 25 EC 2ml/lit or monocrotophos 36 WSC 1ml/lit • Use yellow sticky trap at 15/ha Recently the turmeric crop is also found infested by scale insects viz. Aspidiella sp. Responsible for deteriorating the quality and germination percentage of turmeric and ginger rhizomes.

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Lecture 40: (INSECT PESTS OF BETELVINE) 40. Insect pests of betelvine-distribution-marks.of identification-biology nature and symptoms of damage and management strategies of shootbug and Spodoptera.

1. BETEL VINE SHOOT BUG Disphinctus politus Miridae: Hemiptera (Pachypeltis polytum) • The adult bugs are dark red or reddish brown with a dark head and antennae. The female bugs are relatively larger than the male bugs. Newly emerged nymphs are red and when fully grown they turn to reddish brown. • Both nymphs and adults suck the sap from tender leaves by puncturing the tender tissues. Fading is generally done in between veins which result in producing dark, angular patches on the leaves.

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Tobacco caterpillar Mealybugs

Spodoptera litura Ferrisiana virgata

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The female bug lays elongated, stalked and slightly curved eggs singly inserted in the tissues of tender stems which can be located by their stalks coming out. Newly emerged nymphs start sucking the sap from the tender leaves by puncturing tender tissues and become adults in a period of 12 days (April – May) and 18 days (Jan-Feb) after passing through five months. Reddish brown adults take shelter under drooping bent leaves. When disturbed, they fly away and the nymphs drop to the ground. The warm humid weather prevailing from June to October favours rapid multiplication of the pest. During cold months of December and January its activity shows down. By spraying with nicotine sulphate @ 1.259 kg in 900 lt of water. (100 to 1400 lt of spray fluid is required per ha of Betelvine garden) and giving two days interval between spray and picking of leaves. Spraying with Malathion 0.1% at fortnightly intervals.

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Lecture 41: (INSECT PESTS OF ONION & CORIANDER) 41. Major insect pest of onion-nature and symptoms of damage and management practices of thrips; Minor insect pest of onion-nature and symptoms of damage and management practices of Spodoptera exigua; Insect pests of coriander-nature and symptoms of damage and management practices of aphids and leaf eating caterpillar.

1. ONION THRIPS Thrips tabaci Thripidae: Thysanoptera • Onion crop suffers heavy losses from thrips. • Thrips are the most important insect pests on onions. • Adults are yellowish to yellowish brown with narrow wings. • Eggs are laid in clusters in leaf tissues. • Numerous nymphs and adults are observed between leaf sheaths and stems lacerating the epidermis of leaves and sucking the exuding cell sap. • The affected leaves show silvery blotches which later turn into brownish colour. • Small white patches are seen on leaves. • In case of heavy infestation, leaves are seen with small patches giving whitish appearance to the whole onion crop • The leaves get distorted from tips downwards and plant ultimately wilt and dry away. • Seedlings are killed due to heavy infestation and the plant growth is retarded. • The shape and size of bulbs as well as yield is affected by thrips.

2. HEAD BORER Helicoverpa armigera • The head borer is a serious pest of onion seed crop in Northern India. • The larva of this insect cuts the pedicel of the flower and feeds on the stalk. • Single larva damages many flower stalks.

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Soil application of Phorate or Carbofuran granules (1kg a.i./ha) is also recommended. Alternate spraying of 0.07% Endosulphan (2ml/litre of water), or 0.07% Nuvacron (2ml/litre of water) or 0.01% Cypermethrin (1ml/litre of water) along with a sticker (Triton or Sandovit) at fortnightly intervals controls the insect. Same control measures as that of chilli thrips.

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The fully-grown larva is greenish with dark brown grey lines along the side of body and measures about 35-45 mm in length. Spraying Endosulfan (2-3 ml/litre of water) along with sticker (Triton/ Sandovit) is recommended to control the insect.

3. CUT WORMS Agrotis ipsilon • The larvae of this insect are seen in nursery beds and newly transplanted onion fields. • The tender plants are found damped at ground level during the night • Young larvae feed gregariously on foliage but later segregate and enter into soil. • Young larvae are yellowish grey and later on become brown, greasy to touch and coil when disturbed. • They cut the seedlings at ground level during night and hide during day. • Soil application of Carbofuran (1kg a.i./ha) at the time of planting is recommended. • Chlorpyriphos (5ml/litre of water) also gives good control of this pest.

4. CUTWORMS Spodoptera exigua

Noctuidae: Lepidoptera

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5. CORIANDER APHID Hyadaphis coriandri Aphididae: Homoptera • The nymphs and adults infest the shoot and inflorescence and suck the sap secrete honey dew, sooty mould develops on it. Devitalization of plant occurs. • Same control measures as that of other aphids control.


Lecture 42: (INSECT PESTS OF FLOWER PLANTS) 42. Major insect pests of rose-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of thrips and scales; Minor pests of rose-nature and symptoms of damage and management strategies of leaf eating caterpillar and chaffer beetle; Major insect pests of jasmine-distribution-marks of identification-biology nature and' symptoms of damage and management strategies of stink bugs; Minor insect pests of jasminedistribution-marks of identification-biology-nature and symptoms of damage and management strategies of gall mite; Major insect pests of chrysanthemum-distribution-marks of identification-biology-nature and symptoms of damage and management strategies of aphids.

1. ROSE THRIPS Rhipiphorothrips cruentatus Thrips tabaci • Nymphs and adults – lacerate the tissues from the under surface of the leaves. Suck the oozed out sap. Silvering or white streaks appear on the infested leaves. Leaves show brown patches and get distorted, finally wither and drop down. • Damage to the rose bud is most noticeable in light colored roses, although thrips may attack all roses. If the buds open at all, the petal edges may look brown or discolored. Sometimes the buds will only partially open. Sometimes, the buds will simply wither and die. • Infested flowers do not open; flowers fade and fall off down prematurely. • Spray methyl demeton 2ml (or) phosalone 2ml / lit (or) neem oil 3%

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2. ROSE APHIDS (Penu Banka) Macrosiphum rosaeformis Macrosiphum rosae Aphis gossypii


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Myzus persicae Nymphs and adults are found in clusters on the tender shoots, flowers and buds and suck the sap. Withering of tender shoots Buds fall off prematurely and the flowers show fading.

3. RED SPIDER MITE ON ROSES

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Tetranychus cinnabarinus T. urticae Feed on the undersurface of leaves and are found covered with silken webs. Yellow spots appear on the upper surface and leaves turn reddish due to feeding. Affected leaves finally wither. Growth and flower production are adversely affected. Spray dicofol 2 ml (or) wettable sulphur 2g/lit.

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4. HAIRY CATERPILLARS ON ROSES Euproctis fraterna Euproctis scintillans (Tussock caterpillars) Lymantriidae: Lepidoptera • Caterpillars defoliate the rose plants.


5. CASTOR SLUG CATERPILLAR ON ROSES Latoia (Parasa) lepida Cochlidiidae : Lepidoptera • Caterpillars defoliate the plants. • Spraying with Monocrotophos 0.04% or Phosphamidon 0.05% or Carbaryl 0.15% after removing all flowers. 6. CASTOR SEMILOOPER ON ROSES Achaea janata • The semilooper defoliate and and also cause sever damage eating the rose petals, during monsoon season. • This pest is very common on roses of RARS, Jagtial.

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7. ROSE CHAFFER BEETLES Oxycetonia versicolor Cetoniidae: Coleoptera • Adults feed on leaves and flowers during night. • The beetles feed on buds and flower, result in irregular feeding marks. • The pest is commonly seen in rose garden of Agril College, Jagtial. • Hand picking of beetles. • Treat the soil around the trunk with carbaryl 10% Dust @ 30 g/plant • Spray methyl parathion 50 EC or endosulfan 35 EC or malathion 50 EC at 2 ml/l of water


8. JASMINE STINK BUGS Green stink bug Nezara viridula Brown stink bug Halyomorpha halys Antestiopsis (Antestia) cruciate Pentatomidae : Hemiptera • Nymphs and adults stages of the bug suck sap from flowers and tender portions of the plant. Flowers are heavily damaged. • Spraying with Malathion 0.16% or Monocrotophos 0.04% or Phosphamidon 0.05% after removing all flowers including very tender ones.

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9. JASMINE GALL MITE Aceria jasmine • The symptoms due to damage by the mite appear like a disease. • The mite attack starts in March and reaches a peak during rainy season. • Maximum damage due to this pest is seen in the north of September. • The mites scrape the tissues and feed on the sap, resulting in white leathery growth on tender leaves and growing tips. • As a result, the leaves get wrinkled, discoloured and flower buds are malformed leading to a drastic reduction in the growth and yield. • Management of the pest involves regular monitoring of plants for symptoms of mite attack when monsoon starts and removal and destruction of infested twigs in the initial stages. • Chemical control measures should be taken up as soon as the mite are observed on leaves. • Sprays of triazophos 1.5 ml/l in combination with neem oil 5 ml/l twice or thrice fortnightly provide effective control. • The oil and insecticide combination can be prepared by adding 500 ml of oil to 1.5 to 2 litres of water along with required quantity of sandovit or teepol and mixed thoroughly till it becomes a milky white solution. To this 150 ml triazophos is added and the volume is made up to 100 litres of spray solution. Monocrotophos 2 ml/l or wettable sulphur 3 g/l sprays also provide protection against mite attack.


10. JASMINE BUD BORER (Malle Mogga Toluchu Purugu) Hendecasis duplifascialsis • The caterpillar bore into the bud, causing the deformity and discoloration. • The pest is sever during rainy season, and is common in Jasmine garden of RARS, Jagtial. • If slightly damage occurs, these insecticides recommended will be: deltamethrin (12 cc), methomyl (12 gm) and monocrotophos (20 cc) (with 20 litre of water).

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11. CHRYSANTHEMUM APHIDS Macrosiphoniella sanborni • Cosmopolitan, found throughout India. • Nymphs and adults suck the sap from under surface of leaves and terminal shoots. • Stunted growth of the plant • Curling of leaf • Withering of flowers. • Aphids are black (or) chocolate brown in colour • Aqueous spray application of Vercillium lecanii (Vertilec) @ 15 g/lit (108 CFU/g) • Application (ultra low volume) of the entomogenous fungus V.lecanii • Neem formulations can be used in rotation with regular insecticides • Spray any following insecticides malathion 50 EC @ 1 ml/l of water, endosulfan 35 EC or @ 2 ml/l of water.


Lectures 43-44: (INSECT PESTS OF STORED PRODUCTS) 43. Stored grain pests-biology-preventive and curative measures of rice weevil, lesser grain borer, red flour beetle, khapra beetle, cigarette beetle, pulse beetle and groundnut bruchid. 44. Stored grain pests-biology and preventive and curative measures of saw toothed beetle, rice moth and angoumois grain moth. In order to develop facilities for Applied Research and Apex Level Training in the field of storage and preservation of food grains, a Grain Storage Research and Training Centre was established at Hapur in 1958 which was later expanded into Indian Grain Storage Institute with two field stations at Ludhiana and Bapatla (later shifted to Hyderabad) with the financial assistance from UNDP in 1968. Three field stations at Jabalpur, Jorhat and Udaipur were subsequently established in 1981. These field stations were primarily established for conducting intensive studies on the problems of handling and storage of wheat, rice, millets, pulses and oilseeds and were, therefore, located in different agro-climatic zones of the country predominantly suited to those commodities. In 1996, the IGSI was renamed as Indian Grain Storage Management and Research Institute (IGMRI). IGMRI, Hapur operates in the States of Uttar Pradesh, Bihar, Haryana, Madhya Pradesh, Jharkhand, Chattisgarh, Rajasthan, Delhi, Gujarat, Daman & Diu and Dadra & Nagar Haveili. While the Research and Development & Training activities are undertaken by IGMRI, the work of popularizing scientific methods of food grain storage developed by IGMRI among farming community is implemented through the Save Grain Campaign teams In order to realize the full benefits of increased agricultural production, grain should be protected from loses during post harvest period. Grains during storage are subjected to the damage by insects, mould, mites, rodents and birds. Among these causal agents, insects account for the huge losses sustained during storage. If timely measures are not adapted to arrest their multiplication, practically the entire stock is riddled with filthy dust, excretion and dead bodies of the insects. It is estimated that in India, 65-70% of food grains annually produced are stored by farmers and 3035% only by traders and government agencies. Simple surveys in India indicated that the losses during post harvest handling and storage are found 15% annually during storage. An FAO estimate of worldwide annual losses in store has been given ass 10% of all stored grains. Apart from visible damage, pest attacks may also initiate a change of biochemical changes inside the grain kernel affecting the nutritive value and quality in general.

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Types of Losses • Losses to harvested produce may be of qualitative or quantitative. There are various ways in which produce gets deteriorated between harvest and consumption, resulting in changes in the appearance of products, due to chemical changes in the produce, growth of micro-organisms, development of insects, mites, feeding by rodents etc. • Losses are caused many ways 1. Weight loss 2. Food loss 3. Quality loss 4. Monetary loss 5. Loss of good will (in reputation) and 6. Seed loss. • The importance of availability of good seed is recognized by all farming communities. • Loss of seed results from both external and internal factors. • Physical factors such as light, moisture temperature, biotic factors such as insects, mites etc., impair germination.


Classification of Stored Produce Insect Pests: • They are classified as major or minor depending upon their severity of damage they inflict on a particular commodity. • Two types of insects are found infesting stored food grain. Hard bodied beetles and Soft bodied flying insects popularly known as moths. Beetles are more harmful than moths as they consume and excavate the grain both in larvae stage and also in some adult stage. Moths are harmful only in larvae stage. • Stored grain insects can be classified as Internal and External feeders. In general, pests which complete their life cycle inside the grain kernel are most destructive than those which complete their life cycle outside in the grain mass. Sources of Insect infestation • Field infestation (pre harvest): Rice weevil, bruchids, angomois grain moth. • Migration of insects from infested sources Eg: rice weevil, red flower beetle, angomois grain moth. • Wooden or bamboo granaries and floor cracks and crevices • Bins and old gunny bags of old grain. • Nearness to feed rooms, bins or other stock of feed • Seed brought to the farm from infested sources • Accumulation of waste grain or feed • Temporary storage in the villages • Grain stored in the open or poorly constructed storage structure and during transport.

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1. GRAIN WEEVILS (Mukku Purugu) Rice weevil : Sitophilus oryzae Maize weevil : Sitophilus zeamais Granary weevil : Sitophilus granaricus Curculionidae: Coleoptera • This is an internal feeder. • A Major insect pest of stored grains. • Hard bodied beetle can cause cross infestation. • The Rice Weevil is originally from Asia, but is now found around the world as a pest species transported in grain. • The grain weevil is worldwide and is found throughout India. • Cosmopolitan pest. • More injurious in warm, humid countries. • This pest is native of India. • Rice weevil, Sitophilus oryzae is the commonest and the most destructive pest of stored grain.

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Field Infestations: Insects like bruchids or Sitotroga spp fly from stores to field and lay eggs upon maturing grains or pods. These eggs hatch out to larval in favorable conditions when grains reach the stores. This is termed as cross infestation (field to store) Cracks and Crevices: When storage godowns or containers are emptied, cleaning is not thoroughly done. Some grains continue to lie in cracks and crevices. Insects present in the stores keep on feeding and multiply during the period also. If fresh stocks are kept in such store, the same get infested. Insects from old stocks can crawl or fly to fresh stocks and infest them. This process is called hidden infestation (store in store)


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Biology: Adult rice weevils survive for up to 2 years. Females lay 2-6 eggs per day and up to 300 eggs over their lifetime. The female uses strong mandibles to chew a hole into a grain kernel after which she deposits a single egg within the hole and seals the hole with secretions from her ovipositor. The larva develops within the grain, hollowing it out while feeding. It then pupates within the grain kernel and emerges 2–4 days after eclosion. 3-4 generations are completed in a year.

2. LESSER GRAIN BORER (Lakka purugu) Rhizopertha dominica Bostrychidae : Coleoptera • Cosmopolitan beetle. • Originally it is inhabitant of India. Now spread to the rest of the world. • Very destructive primary pest of stored grains. • A Major pest belongs to hard bodied Beetles. • An Internal Pest. Revised during 2011

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Sitophilus oryzae, Sitophilus zeamais and Sitophilus granaricus are similar in size and appearance and are found together feeding upon rice, wheat, maize and other grains. Among these three grain weevils S. zeamais is the largest in size. The rice weevil Sitophilus oryzae is also found in the paddy fields. They are often found in grain storage plants, processing plants, kiranam shops, but are not often found in the home. They attack rice, wheat, maize, Jowar, and cause similar type of damage. The Rice Weevil is a small dark brown weevil with a long snout, and small round dimples on the thorax and ridges along the wing covers. The head and thorax is nearly as long as the wing covers. It is similar to the Granary Weevil (Sitophilus granarius) which is slightly larger and has plain brown wing covers and oval dimples on the thorax. The Granary Weevil is wingless whereas the Rice Weevil has wings and can fly. The larvae are white or creamy white grubs with a small light brown head. Both grubs and adults do the heavy damage, particularly in the monsoon (JulyNovember) The weevils have the habit of destroying more than what they eat. Grains are hollowed out. Kernels are reduced to mere powder. Adult weevils cut circular holes. Under favorable condition, it is found in large numbers, and due to respiration “Hot Spots” are developed in the grains. Heating occurs in storage bins / godowns in severe infestation.

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The lesser grain borer is a serious pest of stored grain and cereal products. Both grubs and adults cause serious damage. The adults and larvae bore into grain seeds and eat the kernel leaving a hollow husk. Beetle is more harmful than grub. They feed inside the grains and reduce them to mere shells, having many irregular holes. The grubs eat out the starchy contents of grains, which are reduced to frass and waste flour. Adults are powerful fliers and can migrate from the one godown to another causing fresh infestation. Adults produce a considerable amount of frass, spoiling more than they eat. The flour so produced serves as feed to young grubs till they enter the grain. The first instar larva are straight, hence it can bore into sound grain and also damaged ones (from the hole mage by adults), but in the latter stages it is curved (scarabiform), it becomes difficult for them to penetrate the grain.

Adult females lay their eggs singly or in groups of up to thirty eggs. The eggs are laid on the outside of a grain or in the powdered "flour" from damaged seeds, and are glued. Egg period: 5-9 days. After hatching grub crawls, feeds on the flour produced Revised during 2011

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They are mainly a pest in stored wheat and corn, but can also infest nuts, beans, dried fruit, peanuts, potatoes, tamarind, pumpkin seeds and various other types of stored food such as biscuits etc. Particularly a pest of un-husked paddy. The Lesser Grain Borer is a small black or dark brown beetle. The body is slender and cylindrical. The head is hidden under the prothorax which is finely textured with bumps and dimples. The elytra (hardened front wings forming the shell) have rows of pits along their length. The antennae have 10 segments with the last 3 forming a club shape. The larvae are white, stout and c-shaped.

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by young adults, and then burrows into slightly damaged grains, and completes remaining life inside the grain. The lifecycle from egg to adult takes about 60 days, but may take as few as 30 days in warm conditions. Larval period: 45 days. The larva pupates inside as hollow seed or in the accumulated powdered flour from the infestation. Pupal period 7-8 days. The adult on emergence remains inside for some days and comes out by cutting the grain. The male lives longer. There are 5-6 generations in a year.

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Both the beetles, known as "bran bugs," primarily attack milled grain products, such as flour and cereals. Both adults and larvae feed on grain dust and broken kernels, cause considerable damage to flour and flour products, but not the undamaged whole grain kernels. Incapable of feeding on sound grains. These beetles often hitchhike into the home in infested flour and can multiply into large populations. Some survive on food accumulations in cabinet cracks, crevices, and furniture. They are always found hidden in the food. Revised during 2011

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3. FLOUR BEETLES (Pindi Erra Lakka Purugu) THE RUST RED FLOUR BEETLE Tribolium castaneum Tribolium confusum Tenebrionidae : Coleoptera • It is a worldwide stored product pest. • Red flour beetles attack stored grain products (flour, cereals, pasta, biscuits, beans, nuts, etc.) causing loss and damage. • They may cause an allergic response but are not known to spread disease and cause no damage to structures or furniture. • The red flour beetle is of Indo-Australian origin and less able to survive outdoors than the closely related species Tribolium confusum. It has, as a consequence, a more southern distribution, though both species are worldwide in heated premises. • The adults are long-lived and may live for more than three years. • Adults are a small reddish brown or brick red smooth beetle, measures about 3.5 mm in length. Distinction between Tribolium castaneum and T. confusum is that compound eyes are completely noticed and antennae are not gradually thickened in the later when as in the former. The antennae have a clear 3 segmented. Tribolium castaneum is more common sp. In this species its wings are functional. • Grub is yellowish white in younger stage and turns reddish yellow, becomes hairy and measures over 6 mm in length.


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In addition to milled grain products, beetle have been found in barley, breakfast cereals, corn, cornmeal, crackers, flour, millet, oats, rice, rye, wheat and wheat bran, nutmeats, dried fruits, legume seeds, beans, milk chocolate, cottonseed, peas, powdered milk, sunflower seeds, vetch seeds, spices, herbarium and museum specimens, and even baits poisoned with arsenic's. It is particularly injurious in warehouses and in factories making starch products. Flour infested by the larvae has a greyish colour and a tendency to go mouldy. In severe cases, the flour turns grayish and moldy, gives disagreeable odour. Becomes unfit for human consumption. Biology: This is a very prolific species. Both beetles breed in damaged grain, grain dust, high-moisture wheat kernels, flour, etc. Female beetles each lay 300 to 400 eggs in flour or other foods during a period of five to eight months (two to three eggs per day). Within 5 to 12 days, these eggs hatch into slender, cylindrical, white larvae tinged with yellow. The length of the larval period varies from 22 to more than 100 days; the pupal period is about 8 days. Fully grown larvae transform to naked pupae, and in a week adults emerge. The life cycle requires 7 to 12 weeks, with adults living for 3 years or more. Ideally this type of beetle prefers temperatures of 30°C and will not develop or breed at temperatures lower than 18°C.

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Adults are harmless, and damage caused by only larva/grub. Only the grubs cause damage and they eat the grain near the embryo and enter inwards. The grub first attack at embryo point, but later when infestation is sever, other parts of the grain are also badly damaged. Revised during 2011

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4. KHAPRA BEETLE Trogoderma granarium Dermestidae : Coleoptera • Internal feeder. • Khapra beetle is s native of India but it has gone abroad and spread in other countries. • It is very destructive pest of wheat and other grains viz., sorghum, rice, barley, grain, maize, pulses, walnut and other dried fruits etc. • The khapra beetle is synanthropic (associated with man or with human dwellings). Occurs in grain stores, food stores, malthouses, seed processing plants fodder production plants, dried milk factories, merchant stores, stores of packing materials (used sacks, bags , crates). • The beetle occurs in hot, dry conditions, predictably in areas which, for at least 4 months of the year, have a mean temperature greater than 20oC and an RH below 50%. • Adult is a small dark brown beetle 2-3 mm long with practically no distinct division of head thorax and abdomen. Convex and oval in shape. Male is smaller and darker than female. The adults are incapable of flying. • Grub is yellowish brown with brownish head and clothed with long hairs 40 mm long.


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They usually confine themselves to the upper 50 cm layer of grains in a heap or to the periphery on a sack of grains, as the pest do not penetrate beyond some depth. This is due to the fact that in its egg, pupal and adult stages the beetle is highly susceptible to reduction in oxygen tension. A female beetle lays 13-85 eggs in 1-7 days @ 1-25 eggs per day. Egg period 3-5 days. Larval period 20-40 days. Pupation takes place in the last larval skin among the grain. Pupal stage lasts 4-6 days. There are 4-5 generations in a year.

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5. PULSE BEETLE / BEAN BEETLE / SEED BEETLES / THE GRAIN DHORA (Aparaala Purugu) Callosobruchus chinensis Bruchidae : Coleoptera Callosobruchus analis Bruchus pisorum • It is a serious pest of grams, mung (Phaseolus aureus), peas, cowpeas, lentil, redgram and other lugiminous seeds. • Also reported on cotton seed, sorghum and maize. • This pest has been reported from USA, Africa, China, Philippines, Japan, Indonesia, Srilanka, Burma and India. • Adult beetle is oval, reddish brown, measures about 3-4 mm in length, active, with two ivory coloured spots in the middle of the dorsal side of its body. • It can fly readily. • It has a conspicuously swollen abdomen. • Grub is white, cylindrical, fleshy with a light brown head and measures 3-4 mm in length. • Infestation may occur in field itself. Damage generally starts in the leguminous pods in the field from where they are carried to store godowns. However, they do serious damage in storage. • In Bengal gram, there would not be field infestation while redgram and horse gram are infested. For redgram field infestation is more than horse gram (Horse gram grain is flat and interspace is less). • Both grubs and adults cause damage by eating out the entire content of the grain, leaving only the shell behind. • Damage to pulses, infested with pulse beetle is very high and often each and every grain is infested. • The pest infested pulses become unfit for human consumption such infested grains is often converted into flour. • The damaged also unfit for sowing (seed) purpose.


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The maximum damage is cause during July-September. The losses may go as high as 60% in severe cases. A single female beetle lays 30-110 eggs @ 1-37 per day. Only one egg is laid on one grain egg stage 4-16 days. The young larva bores into the grain and completes inside its development. Larval stage 10-12 days. Hibernation in winter takes 117-168 days to complete their development. The full grown larva migrates towards periphery and comes to lie next to the seed coat where it turns into an oval, white pupa. Puapal stage 4-28 days. There are 7-8 overlapping generations in a year.

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6. CIGARETTE BEETLE / TOBACCO BEETLE / DRUG STORE BEETLE Cigarette Beetle Lasioderma serricorne Drug Store Beetle Stegobium paniceum Common Furniture Beetle Anobium spp. • Lasioderma serricorne, commonly known as the cigarette beetle or tobacco beetle, is very similar in appearance to the drugstore beetle (Stegobium paniceum) and the common furniture beetle (Anobium punctatum), and all three species belong to the family Anobiidae. • Lasioderma serricorne is around 2–3 mm long, and brown in colour. • The beetles, which can fly, live 2–6 weeks and adult beetles do not feed during their life. • Lasioderma serricorne have thoraxes which have a much less obtuse looking angle when viewed from the side • As indicated by its common name, the cigarette beetle is a pest of tobacco, both in the refined cigarette packet presentation and also as stored in hogsheads and bales, but is also a minor pest of oilcake, oilseeds, cereals, dried fruit, sage, flour, and some animal products. • The female beetle lays around 100 eggs loosely on the commodity. The hatching larvae are the "grow bag" stage of the insect are active and will move around on and bore into the product, feeding as they go. The complete life cycle takes 26 days at 37 °C and 120 days at 20oC. L. serricorne cannot tolerate the cold; adults die within 6 days at 4 °C, and eggs survive 5 days at 0–5 °C. • The beetles carry a symbiotic yeast, Symbiotaphrina kochii, that is transmitted to the next generation superficially on the eggs and carried internally in larvae and adults in the mycetome, a specialized organ that is linked to the gut. The yeast cells assist in the digestion of less nutritious foods, supply needed B-vitamins and sterols, and provide resistance to certain toxins.


7. SAW TOOHED BEETLE Oryzaephilus mercator Oryzaephilus surinamensis Silvanidae: Coleoptera • Adult is a narrow flattened and long beetle thorax having 6 teeth like structures on each side. • Larva is slender pale cream with two darken patches on each segment. • Both grubs and adults caused scraping on the grain surface. • The grub feeds mostly on flour, maida or the waste flour produced by other primary pests. • Adult also attacks damaged grains infestation on cereals and products make them unpalatable and saleable. • Female lays about 300 eggs loosely in cracks of storage receptacle or godwns. Egg stage 3-17 days. Grub move freely in grain. Larval stage 14-20 days Pupal period 721 days. Adult survives 6-10 months. In coastal areas during rainy season, multiplication of this pest is quick.

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8. GROUNDNUT BRUCHID / PEANUT BRUCHID Caryedon serratus Bruchidae: Coleoptera • Among the insect pests attacking groundnut especially during storage, is the groundnut bruchid, Caryedon serratus which is potentially the most important one as it is the only insect species known to infest both kernels and intact pods. • Also effect tamarind, and is called tamarind seed beetle. • The adult is a reddish brown beetle. Female beetle attaches its eggs to the pod wall. The eggs are small and milky-white in colour and hatch in about 8 days. Grubs are stout and fleshy and they complete four instars in about 23 days. Full grown grub makes a round hole on the pod wall through which it leaves the pod and pupate at the bottom. Pupal period ranges between 14 and 16 days. • Grubs bore through the pod wall, feed on the internal contents of the seed and make them hollow.


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Drying the pods to less than 8 per cent moisture before storing. Separation of damaged seeds before storage in the godowns. Maintenance of hygiene in the godowns. Care should be taken that no live insect pests are present in the produce or in the storage areas. Monitoring of the insect presence is the basic and preliminary step in the successful management of the beetle. Installation of two-in-one model trap developed by Tamil Nadu Agricultural University (TNAU) is very much helpful in this regard.

Biology: Adults do not feed and live for one to two weeks. Through this period and within short-range, rice moth males are attracted to the female abdominal-tip pheromone that causes the male moths to search for a mate and attempt copulation. Mated females lay from 100 to 200 eggs near food sources. Eggs hatch in 4-10 days. Larvae spin silken threads as they feed and web grains, debris and other particles into galleries in which they live and feed. When they are fully-grown, they form dense Revised during 2011

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9. RICE MOTH (Biyyam Chuttu Purugu) Corcyra cephalonica Gallariidae : Lepidoptera • Rice moth, Corcyra cephalonica (Stainton) is a worldwide-distributed insect. • Adapted to warm humid environments. • The larvae are general feeders and considered one of the key pests of rice, cocoa, biscuits, pearl millet, sorghum and seeds. • It is distributed in Asia, North America and Europe. • Adult is a pale, grayish brown coloured moth. Bigger than other grain moths. • Larva is dirty creamy white coloured with a prominent broad, yellowish head. • Besides feeding on rice, it also infests gram, sorghum, maize, groundnut and cotton seed. • Larvae also contaminate foods by secreting silken threads that web together food particles, dusts and frass “debris or excrement produced by insects”. • These will render infested products unaccepted for sale, manufacturing and consumption. • Larva only damages the grain of rice and maize by feeding under silken webs. • The entire stock of grains may be converted into a webbed mass in severe infestation of pest. • It gives characteristic bad odour and such grains become unfit for human consumption. • The adult moth has pale buff-brown forewings with ½-1 inch wingspan, hindwings almost transparent and uniform in color. The wing tips are rounded and tightly folded to the body when at rest. There are no distinctive markings on the wings, although veins may be slightly darkened. • The larvae are dull white, with long fine hair and dark brown head. • Cocoons are white in color.


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Management of Rice Moth: (Only preventive measures works, and no curative measures can be followed in any case) Prevention: • Avoid purchasing old food items and always use older food first. • Store foods in insect-proof containers with tight-fitting lids and keep highly susceptible foods, such as rice, cocoa, biscuits and millet in the refrigerator or in the freezer. • Store food products in a dry, cool, well-ventilated area (below 60°F and less than 20% RH) “rice moth life stages are not active under these environmental conditions” • Regularly inspect and immediately vacuum all spilled foods materials • Clean shelves with soap and hot water, allow to dry and cover with clean, fresh paper or foil before placing any food or cooking utensils. • Heat or Cold Treatments: Place infested foods in a freezer at 0°F for four to seven days or heat at 140°F for one hour or 120°F for two hours. To avoid damaging certain items, check the product’s label before any heat/cold treatments, i.e., seeds saved for planting may have the germination reduced after superheating or cooling. Practically, during the winter, in northern states, or where the daily mean temperature falls and remains below the freezing point (32°F), placing infested materials covered with plastic sheeting outside in a trailer for one to two weeks will provide sufficient elimination of rice moth life stages. • Physical Removal of the Rice Moth Life Stages “discarding infested materials”: Remove Cocoons: Cocoons could be found on the food surface, bin walls or between bags. Remove cocoons around food products by vacuuming, seal the vacuum bag and properly discard outside the building. Infested materials with cocoons should be destroyed as aforementioned in the heat and cold treatment and then property discarded outside the building; Remove Eggs and Feeding Larvae: All infested materials should be double-bagged, firmly sealed and discarded outside the building. • Capture the flying Adults using pheromone of insect light traps (ILTs): Traps alone are not a control method. They are important tools for detecting, monitoring and pinpointing stored product pests including rice moth. Proper placement of the traps is very crucial for a successful monitoring program and it depends on the understanding of the insect feeding, flying and mating behaviors. If commercially available, use sex pheromone lure traps to attract and then capture newly emerged males. Place pheromone traps in a grid pattern at 20 to 60 feet apart in infested and hard-to-clean areas as well as in places conducive to pest infestation such as commonly spillage areas. Avoid placing pheromone traps in the following places: Near doors, windows, vents, or loading docks where they could attract insects from outside. In moist and air current areas to avoid attracting insects to non-target areas. Number each trap and map your traps in each location.Check traps on a regular basis, usually weekly, and locate traps that captured more moths than other traps. Around tarps with more catch, tighten the grid to pinpoint the source of the infestation. For example, place traps at five to six feet parts around the one with the catch. Keep a monitoring record of each trap’s location in the grid, the date it was placed, and its catch at each inspection. Based on the data collected from the pheromone traps, make your pest management decisions. Adults of rice moth fly mostly at night and are attracted to lights; therefore, install ILTs which use ultraviolet light to lure and capture the flying adults Place one ILT every 12-25 feet in the entryway or as recommended by the ILT manufacture’s label. When installing the ILTs, note the following: Do not place ILTs too close to the doorways or the moth will not recognize them. Do NOT use ceiling mounted ILT’s in

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white cocoons to pupate. Pupae are usually found in food or they may be found between pallets and sacks. Adults emerge from pupae within four to eight weeks and repeat their life cycle. At optimal temperatures of 86 - 90.5°F and relative humidity of 70%, the life cycle lasts 28-35 days. The low minimum temperature and low relative humidity (RH) of the rice moth are 60°F and 20%, respectively. However, there are up to six generations per year in tropical countries and one generation in temperate climate.


food preparation areas. Electric Grid ILT’s should be mounted a minimum of 10 feet from any food preparation surface. Adhesive ILT’s should be mounted a minimum of three feet horizontally from any food preparation surface. Mark all the ILTs on a map Regularly check collecting trays and glue boards, usually weekly, to determine insect ID, insect category (i.e., stored product insects, flies, or occasional invaders) and the source of infestation. Periodically replace glueboard before it becomes clogged. Replace the UV lamp twice a year or as needed. Follow the same recordkeeping measures previously described in the pheromone trapping method. • Chemical Methods: Before treatment, discard all infested products outside the building and remove food, water and clothing materials from areas to be treated. Apply a space treatment with an EPA approved non-residual insecticide to knock down the adult populations in warehouse and food processing facilities. Target feeding, breeding and harborage areas using EPA approved residual insecticides as crack, crevice and spot treatments. Apply crack and crevice treatments in pantries, closets, baseboard, doorframes, window frames and other similar places. Apply a spot treatment to surfaces near food storage areas, in and around cabinets, under and behind machines, appliances and furniture; remove shelf papers, and treat where food IS NOT present. If applicable, apply a perimeter treatment to prevent flying adults coming from outdoors. Precautionary Measures • During the treatment, no people, food, or pets should be present in the room to be treated. Fish tanks should be covered and the air shut off. Plants will not be affected. • Do not enter the treated room or use before applied pesticides are dried. • Anyone with a respiratory condition should notify property manager and the Guardian Pest Control Service Specialist Post Treatment Information • Follow up evaluation is necessary 7-10 days after the treatment. • Follow prevention methods and keep monitoring to minimize the periodic space treatments

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10. GRAIN MOTH OR ANGOUMOIS GRAIN MOTH Sitotroga cerealella Gelechiidae: Lepidoptera • Its distribution is worldwide. • Important pest of stored grain such as paddy, maize, jowar, barley and wheat etc. • Does not attack Milled rice or other cereal products. • Adult is buff brown or straw colored moth. The characteristic feature is the presence of the narrow pointed wings fringed with long hairs, most prominent along the posterior margin. • Only the larva causes damage by feeding on the grain kernels. Full grown larva measures about 5 mm long with a white body and yellow brown head. • Damage is at its maximum during monsoon (kharif). • The larva bores into the grain and feeds on its contents. • Normally 30-50 per cent of the contents are consumed. • Sometimes whole grain may be finished by the larva. • The grains give out an unpleasant smell during severe infestation of the pest. • In a heap of grain, infestation remains confined to upper 30 cm depth only.


Integrated Management for Stored Grain Insect Pests: • In the management of stored grain pests, prophylactic measures assume greater importance. Prophylactic (Preventive) measures: • “Prevention is better than cure” is the best proverb in practice followed for keeping grains away from insect pests attack. Because, once the pest infestation is seen in produce during storage, it is practically not possible to control. This can be achieved through sanitation and legal provisions Sanitation: • Clean storage area / godowns thoroughly • Burn all the swept materials from godowns. • Clean and Close all crevices/cracks in walls/windows/floor with cement/plaster of paris or mud. • Clean all old gunny bags, and see that no single grain/insect/insect stage is present. • Treat/dip all old gunny bags with 0.01% cypermethrin / fenvalerate or 0.1% malathion solution and dry before use. • Use new gunny bags for sacking grains. • Disinfect the store area/godowns with 0.5% malathion / 0.5% pirimiphos methyl / 0.02% pyrethrin @ 3L/100m3 (Cubic Meter area) • Doors and windows should be repaired without any gaps. • Residues of old stock should not be left in the godown. • Dry the grain in clean floor thoroughly to bring the moisture content below 10% before storage. • Before sacking (filling into gunny bags), clean the grain thoroughly so as to remove damaged grains, and also insects/its stages. Generally at farmer’s level, the bags or containers are kept without proper cleaning for use in the next season. During off season, the eggs and larvae of insects which are hidden in them feed on the grain fragments, infest the food grains when the fresh stocks are filled. • Trucks, trollies and bullock carts: Food grains after harvest and threshing in the field are transported to the godsons or stores by trucks, trolleys, and bullock carts. These are the sources of cross infestation where these insects present in the joints or corners of the carriers. • Threshing yards should be clean and away from godown or stores. • Cracks and crevices, holes in floors, walls etc in the godown stores to be perfectly closed. • All sweepings from the stores are removed and destroyed. • Stores should be white washed before storage. • Before storage, stores should be disinfested with malathion 50% at 1:100 dilution. • Stores should be moisture and rat proof. When the grain has moisture content below 10%, most of the insect spp do not survive or multiply hence grain should be dried properly Revised during 2011

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Female moth lays eggs singly or in batches on or near the grain capable of laying on an average 150 egg per female. Eggs are small white in the beginning, later on turning reddish. Egg period 4-8 days newly emerged larva bores into the grain and feeds on its contents. Larval stage is about 3 weeks. Before pupation larva constructs a silken cocoon in a cavity made during feeding and then turns into reddish brown pupa (inside the grain). Puapl stage 7-13 days. It may hibernate during winter in pupal stage 3-4 generations in a year.

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Mixing of inert dust viz., sand, clay ash etc with grain makes the entry of insect’s grains a difficult task and cause physical injury to insects. This can be employed for controlling insect damage but such grains are to be cleaned before use. • Malathion 50% EC as a spray in ratio of 1:100 with water on food grain bags, walls, floors @ 3 lit/100 sq mts is effective or DDVP 100% EC as a spray in ratio of 1:300 with water on gunny bags, walls, floors etc @ 3 lt per 100 sq.mts is very effective on insects. DDVP acts both as a contract poison and as a fumigant. Note : spraying should not be given directly on food grains. • Mixing of chemical dusts like camphormaphthalene, paradichlorobenzeme, sodium ehloride, sodium carbonate, sodium bicarboniate, compounds of mercury etc., can be mixed with food grains mean for seed purpose only. • At times dried neem leaves, tobacco, pyrethrum dust can also be used. Legal methods: • Entry of insect which is not found in the other area can be prevented by imposing DIP act (Destructive Insect Pests Act of 1914). Non-Chemical Methods: • Ecological: Insect populations in stores can be checked through temperature and grain moisture regulation. Temperature below 14oC results in death of immature stages of almost all insects, and death occurs at freezing temperatures. So, produce which is infested with insect pests, can be stored in cold storage units. So, the grains can be exposed to low temperatures for specified time so as to kill/eliminate all insect stages, and then can be stored. Similarly, most of the stored grain insects die at 50-60oC within a period of 10-20 minutes. Exposure of grains/sacks to high temp for specified time eliminates the insect pests. All these practices followed under the guidance of technician as per the recommendations. • Ecological: Controlled atmosphere disinfestations technology involves the alteration of natural storage gases i.e. CO2, O2 and N2 so as to prevent the multiplication of insects. About 9.0-9.5% CO2 in air is lethal to insects. So, under controlled atmospheric chambers, the grains can be disinfested before being stored, or even during storage in controlled conditions, the method can be achieved, if the insect infestation is found. • Non-Toxic, Plant based Grain Protectants: Inert Dusts: Silica, Diatomaceous earth, etc are commonly used by farmers, which kills insects due to desiccation (loss of water); Use of edible oils: Mustard and Groundnut oils @ 7.5 ml/kg grain, can keep pulse beetle away for 9 months; Neem leaves and oils: Products of neem possesses repellant, anitfeedant and feeding deterrent properties against storage pests. NSK Powder 4%, Neem Oil 1% or Mahua Oil 1% proved repulsive, potent oviposion inhibitor for pulse beetle. • Biological methods: Not very effective in stored grain pests. But Trichogramma egg parasitoid can be tried for controlling rice moth, if the infestation is severe. • Cultural: Pulse beetle attack whole pulses only, and hence split pulses can be stored safely from the attack of pulse beetle. • Cultural: Use of improved storage structures: The traditional receptacles used for storage of food grains are not safe from insects, rodents, moisture etc, and also these traditional structures are not suitable for fumigation / disinfestations. Hence, it is suggested to use improved storage structures which can be used by framers, such as pusa bin, gade, patara, kothi, pucca kothi etc. Similarly, for large scale storage of grains, modern storage structures such as cold storage units can be used for large scale

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storage, and also CWC, SWC godowns can also be used for large scale storage where fumigation is possible, if infestation is seen. • Chemical methods (Protective treatments): Knockdown chemicals such as pyrethrum or lindane smoke can aimed at flying insects in godown, before the bags are transported into godown. Similarly, Grain Protectants can be used for grains meant for seed purpose, but is not recommended for grains meant for human consumption. Pyrethrum dust or Malathion 5% @ 250g/Quintal seed can be used. • Fumigation: Aluminium phosphide (Phostoxin, Celphos) tablets @ 7-10 tablets of 3g each can be placed for 10003ft space with an exposure period of 7 days. But, this method is not suggested for Oil Seeds. These tables can placed after the grain sacks are arranged inside the godown for effective storage. Similarly, Ethylene Dibromide (EDB) which is very toxic, available in ampoules, can used @ 3ml/quintal of wheat and pulses, @ 5ml/quintal of rice and paddy. It is also applied @ 1-7 lt for 10003ft space for one week. Before consumptions, all the grains are to be aerated thoroughly. Care should be taken while using the fumigants. Many fumigants such as CS2, CCl4, Chloropicrin, Methyl Bromide (MBr), Phosphine or Hydrogen Phosphide (PH3) are also used under the guidance of technician. Curative measures: • In spite of prophylactic measures, infestation develops due to hidden infestation or cross infestation, especially grains stored in local bins and also godowns. In such cases, only chemical methods can save the grains. Most useful and practical method is fumigation. Fumigation is the process of applying toxic fumes or vapors of gas from to the infested grain for a certain period in a reasonably airtight fumigation chamber or room. Following are the effective fumigants • Ethelene diromide: EDB: Toxic chemical marketed in glass ampoules filled and nozzles sealed. Individual sealed ampoule is wrapped in cotton, blotting paper and then stitched cloth bag when an ampoule with EDB liquid is broken and inserted into grain mass. The EDB changes into vapors. Ampoules are available in sizes of 3 ml, 6 ml, 10 ml, 15 ml and 30 ml. Note: EDB can be used on all food grains but not on milled products, oil seeds and moist grains, prescribed dosage is 3 ml quintal of grain and such stocks are left undisturbed for 7 days. Before consumption the grain, the grain should be exposed out of godown for a week. • EDB+: It is a mixture of EDB and carbon tetrachloride in the ratio of 1:8. It has a greater penetration power and for bagged storage under gas proof covers is very effective. Dosage: 11 ml / quintal. Stocks are left undisturbed for 7 days. • Ethylene dichloride carbon tetrachloride (EDCT): It is a mixture of two chemicals the name indicates in the ratio of 3 : 1 v/v. it is used for large scale food grains fumigation. Dosage: 30-40 kg / 100 cm the stocks are left undisturbed for 36-48 hours. Note: It should not be used on milled products. • Aluminium phosphide (Al.P): Solid fumigant marketed as tablets of 3 gms each packed in seal tubes, potent fumigant and can be used practically on all food grains, milked products etc. active ingrediant is phosphine gas which is an acute toxic poison. Bering highly toxic, should be handled with great case by trained staff only.


Lecture 45: (LOCUSTS) 45. Locusts-phases (solitary and gregarious)-breeding places-migration, damage and control.

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Grasshopper • Grasshoppers belong to family Orthoptera which includes any of the leaping insects of the family Acrididae (short-horned grasshoppers) or Tettigoniidae (long-horned grasshoppers). • The long-horned grasshoppers (family Tettigoniidae) are characterized by antennae longer than the body and auditory organs on the forelegs. • Short-horned grasshoppers (family Acrididae) are characterized by antennae shorter than the body and auditory organs on the abdomen. • Some species of Grasshopper can fly well, others poorly or not at all. • Grasshopper are both herbivorous (plant feeders) and carnivorous (feeding on tiny insects.). • Most grasshoppers feed on crops such as wheat, barley, corn, rye, and oats,which leads to agriculture destruction.

Locust • Locusts are those grasshopper species that belong to the family Acrididae (short-horned grasshoppers). • Locust, the short-horned grasshoppers (family Acrididae) is characterized by antennae shorter than the body and auditory organs on the abdomen. • Locust can live in solitary or form very large groups (swarms).

• All Locust can fly and migrate long distances in destructive swarms. • All Locust are herbivorous grasshopper. • Locust can be referred as the migratory grasshoppers that are serious threat to agriculture.

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Locust is the swarming phase of short-horned grasshoppers of the family Acrididae. These are species that can breed rapidly under suitable conditions and subsequently become gregarious and migratory. They form bands as nymphs and swarms as adults-both of which can travel great distances, rapidly stripping fields and greatly damaging crops. Locusts exist in two behavioural states (solitary & gregarious). When the population is low, locusts behave like individuals, similar to grasshoppers. However, when locust population density is high they form into gregariously behaving bands of nymphs or swarms of adults. In addition to changes in behaviour, phase change may be accompanied by changes in body shape and colour, and in fertility, survival and migratory behaviour. These changes are so dramatic in many species that the swarming and non-swarming forms were once considered to be different species.

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Plagues of the desert locust (Schistocerca gregaria) have threatened agricultural production in Africa, the Middle East, and Asia for centuries. The livelihood of at least one-tenth of the world’s human population can be affected by this voracious insect. The desert locust is potentially the most dangerous of the locust pests because of the ability of swarms to fly rapidly across great distances. It has two to five generations per year. The 2004 desert locust outbreak has caused significant crop losses in West Africa and had a negative impact on food security in the region. The desert locust lives a solitary life until it rains. Rain causes vegetation growth and allows the female to lay eggs in the sandy soil. The new vegetation provides food for the newly-hatched locusts and provides them with shelter as they develop into winged adults. When vegetation is distributed in such a way that the nymphs, usually called hoppers, have to congregate to feed, and there has been sufficient rain for most eggs to hatch, the close physical contact causes the insects' hind legs to bump against one another. This stimulus triggers a cascade of metabolic and behavioral changes that cause the insects to transform from the solitary form to the gregarious form. When the hoppers become gregarious, they change from green-coloured to yellow and black, and the adults change from brown to red (immature) or yellow (mature). Their bodies become shorter, and they give off a pheromone that causes them to be attracted to each other, enhancing hopper band and subsequently swarm formation. Interestingly, the nymphal pheromone is different from the adult one. When exposed to the adult pheromone, hoppers become confused and disoriented, because they can apparently no longer "smell" each other, though the visual and tactile stimuli remain.

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Migratory locust Locusta migratoria

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Desert locust Schistocerca gregaria Very wide distribution (North Africa, Middle East, and Indian subcontinent) Able to migrate widely


After a few days, the hopper bands disintegrate and those that escape predation become solitary again. It is possible that this effect could aid locust control in the future. • During quiet periods, called recessions, desert locusts are confined to a 16-millionsquare-kilometer belt that extends from Mauritania through the Sahara Desert in northern Africa, across the Arabian Peninsula, and into northwest India. • Locust swarms fly with the wind at roughly the speed of the wind. They can cover from 100 to 200 kilometers in a day, and will fly up to about 2,000 meters above sea level (thereafter, it becomes too cold). Therefore, swarms cannot cross tall mountain ranges such as the Atlas Mountains, the Hindu Kush or the Himalayas. They will not venture into the rain forests of Africa nor into central Europe. A single swarm can cover up to 1200 square kilometers and can contain between 40 and 80 million locusts per square kilometer. The locust can live between three to six months, and there is a ten to sixteenfold increase in locust numbers from one generation to the next. • Desert locusts can consume the approximate equivalent of their body mass each day (2 g) in green vegetation: leaves, flowers, bark, stems, fruit, and seeds. Nearly all crops, and noncrop plants, are at risk, including pearl millet, rice, maize, sorghum, sugarcane, barley, cotton, fruit trees, date palm, vegetables, rangeland grasses, acacia, pines, and banana. What is more, locust droppings are toxic, and spoil any stored food that is left uneaten. Management: • Early warning and preventive control is the strategy adopted by locust-affected countries in Africa and Asia to try to stop locust plagues from developing and spreading. FAO’s Desert Locust Information Service (DLIS) in Rome, Italy monitors the weather, ecological conditions and the locust situation on a daily basis. The situation assessments and forecasts are published in monthly locust bulletins that date back to the 1970s. These are supplemented by warnings and alerts to affected countries and the international community. Those since the 1990s are available on the FAO Locust Watch web site [www.fao.org/ag/locusts]. FAO also provides information and training to affected countries and coordinates funding from donor agencies in case of major upsurges and plagues. • At present, the primary method of controlling desert locust infestations is with insecticides applied in small concentrated doses by vehicle-mounted and aerial sprayers at ultra-low volume (ULV) rates of application. The insecticide is acquired by the insect directly or via secondary pickup (i.e. walking over or eating the residue on a plant). Control is undertaken by government agencies in locust-affected countries • Natural enemies such as predatory and parasitic wasps and flies, predatory beetle larvae, birds, reptiles may have limited effects on desert locusts because they can be easily overwhelmed by the sheer magnitude of most swarms and hopper bands. On the other hand, they may be effective in keeping solitary populations in check. • Farmers often try mechanical means of killing locusts, such as digging trenches and burying hopper bands, but this is very labor intensive and is difficult to undertake when large infestations are scattered over a wide area. Farmers also try to scare locust swarms away from their fields by making noise, burning tires or other methods. This tends to shift the problem to neighboring farms, and locust swarms can easily reinfest previous fields. • Biopesticides include fungi, bacteria, neem extract and pheromones. The effectiveness of many biopesticides equals that of conventional chemical pesticides, but there are two distinct differences. Biopesticides in general take longer to kill insects, plant

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diseases, or weeds, usually between 2 and 10 days. A biological control product has been under development since the late nineties. It is based on a naturally occurring entomopathogenic fungus (i.e. insects-infecting fungus), Metarhizium acridum. The product is available in Africa under the name Green Muscle and in Australia as Green Guard. Neem products are also very effective against locusts.

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Locust control and research in India: • The “Locust Control and Research“ is one of the divisions of the Directorate of Plant Protection, Quarantine and Storage, being implemented through an Organization known as Locust Warning Organization(LWO) established in 1939, to monitor, forewarn and control of Desert Locust (an international pest) with its 10 Circle Offices located at Bikaner, Jaisalmer, Barmer, Palanpur, Bhuj, Jalore, Phalodi, Nagaur, Suratgarh and Churu with its field Headquarters at Jodhpur and a Central Headquarter Faridabad. • Besides, there is one Field Station for Investigations on Locusts (FSIL) situated at Bikaner. • To strengthen the locust monitoring and forecasting, a Remote Sensing Laboratory has also been set up to prepare vegetation maps based on satellite imageries for locust forecasting. • The Locust Warning Organization (LWO) monitors locust development/ activities over an area of 2.00 lakh sq km of the Scheduled Desert Area (SDA) in parts of Rajasthan, Gujarat and Haryana States. Wireless communication between Jodhpur (India) and Karachi (Pakistan) is also maintained every year during June to November for exchanging locust intelligence between the two countries. • The greatest achievement of Locust Warning Organization (LWO) is that no Locust Plagues have occurred/ reported since 1962, only due to careful and extensive surveys monitoring and successful control operations undertaken by LWO against exotic swarms and localized small and large scale locust breeding at all occasions. As a result, the devastation of cultivated crops could be avoided by controlling the locust in SDA several times in the past which resulted in the saving enormous crop/vegetation losses. • The locust plague cycles observed in India, during 1812-21, 1912-20, 1926-30, 1940-46, 194955, and 1959-62, and in recent years, upsurges are observed during 1993 and 1997. • Field Station for Investigations on Locusts (FSIL) was established in 1957 at Bikaner, Rajasthan (India) under the Directorate of Plant Protection, Quarantine and Storage of Department of Agriculture and Cooperation (DAC) in the Ministry of Agriculture, Govt. of India. It is a research station for conducting field research on Locust and grasshoppers. This Institution is responsible for conducting research on various aspects of Locusts and Grasshoppers viz. biology, ecology and control in the field/laboratory conditions with ultimate aim of finding out cheaper, more effective and environmental friendly methods of Locust Control. Different Laboratory and field trials are conducted for which a laboratory is maintained. The mass rearing of locust is done in the laboratory and field cage conditions.


Lecture 46: (NON-INSECT PESTS: MITES)

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Mites, along with ticks, are small arthropods belonging to the subclass Acari (also known as Acarina) and the class Arachnida. The scientific discipline devoted to the study of ticks and mites is called acarology. Mites are among the most diverse and successful of all the invertebrate groups. They have exploited an incredible array of habitats, and because of their small size (most are microscopic) go largely unnoticed. Many live freely in the soil or water, but there are also a large number of species that live as parasites on plants, animals, and some that feed on mold. It is estimated that 48,200 species of mites have been described Mites are especially numerous when temperature is high and humidity low. The majority of species spends the winter in a state of diapause. The most common characteristic features of mites are: 4 pairs of legs, although some juveniles only have 3 pairs gaining a forth pair with their first moult, No external segmentation of the abdomen, individuals appear as a single body mass, Never have antennae. Life Cycle: Reproduction in mites and ticks is very variable with some species mating through the direct transfer of sperm via coupling of the genital regions. Other species transfer sperm indirectly with the male placing a sperm droplet on the genital opening of the female with his legs or chelicerae. After fertilisation the female will usually lay her eggs in the substrate where they are left to hatch. The first free-living stage is called a larva and has only 3 pairs of legs. After the first moult it will gain its fourth pair of legs and will moult several more times before becoming a mature adult. Feeding: Most species of mites are predatory and will feed on a variety of small invertebrates, while others are more herbivorous, and often feed on plant sap, sometimes causing damage to agricultural crops and garden plants. Ticks are adapted to feeding on the blood of vertebrate animals such as humans, dogs or livestock. Habitat: Mites are found in almost all habitat types including terrestrial, freshwater and marine environments. Terrestrial mites are commonly found in soil or leaf litter, under the bark of trees or feeding on the leaves and stems of plants. Both mites and ticks can be found living as parasites of other invertebrate and vertebrate animals. Most ticks are only discovered after they have attached themselves to a host animal. Some of the plant pests include the so-called spider mites (family Tetranychidae), thread-footed mites (family Tarsonemidae), and the gall mites (family Eriophyidae). Majority of plant parasitic mite species belong to tetranychidae, and eriophyidae. Only a limited number of tarsonemid genera are known to feed on higher plants while most species in this family feed on the thin-walled mycelia of fungi or algal bodies. Even among the plant-feeding tarsonemid mites, most are confined to areas of new growth where cell walls are thin and therefore easily pierced. However two species (broad mite Polyphagotarsonemus latus and cyclamen mite Steneotarsonemus pallidus) are able to feed on older leaves because of their ability to inject toxins during feeding (presumably of salivary glands origin) causing an increase of thin walled cells surrounding feeding sites. This proliferation of new growth often results in leaves that appear stunted, puckered and twisted. Rice panicle mite Steneotarsonemus spinki

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46. Mites-brief morphology and systematics-mites infesting sorghum, cotton, redgram, coconut, vegetables, chillies, citrus and their management practices.

Eriophyidae Gall mites, Rust mites

Obligate plant parasites • Development from the egg to the adult includes 3 active stages (6-legged larva, 8legged protonymph and deutonymph) alternating with 3 quiescent stages. • These mites live on leaves or on the underside of leaves (more advanced species) where they spin silken webs serving as a protective net against predators. • These mites do not transmit any viruses. Tetranychus urticae (Cotton, Brinjal, Okra, Grapes) Tetranychus telarius (Cotton, Brinjal, Okra) Polyphagotarsonemus latus (Cotton, chilli) Panonychus ulmi Oligonychus indicus (Sugarcane) Paratetranychus manguferus (Mango) Oligonychus mangiferus (Mango, Grapes) Schizotetranychus hindustanicus (Citrus) Eutetranychus orientalis (Citrus) Oligonychus coffeae (Tea) Tetranychus cinnabarinus (Rose mites)

Obligate plant parasites • They are tiny, microscopic mites and are yellow to pinkish white to purplish in color. • The mites are worm like, and have only two pairs of legs. • Eriophyidae is a family of more than 200 genera of mites, which live as plant parasites, commonly causing galls or other damage to the plant tissues and hence known as gall mites. • Their primary method of population spread is by wind. They affect a wide range of plants, and several are major pest species causing substantial economic damage to crops. • Most eriophyoids are highly host specific, and their feeding often causes characteristic symptoms on the host ranging from discolouration of foliage to production of striking galls or erineal excretions on foliage, flowers or fruits

Aceria cajani (Redgram) Aceria guerrironis (Coconut) Calacarus carinatus (Tea Purple Mite) Aceria jasmine (Jasmine Gall Mite) • Insects may also have parasitic mites. Examples are Varroa destructor, which attaches to the body of the honeybee, and Acarapis woodi (family Tarsonemidae), which lives in the tracheae of honey bees. There are hundreds of species of mites associated with other bee species, and most are poorly described and understood. Some are thought to be parasites, while others beneficial symbionts. Rice Panicle Mite (Vari Kanki Nalli) Steneotarsonemus spinki • Serious rice pest in several Asian tropical regions, Central America and the Caribbean. • The panicle rice mite is not visible to the naked eye. • Parnicle rice mites are parthenogenetic (virgin females can produce male offspring). The female will then mate with the male offspring and produce eggs. A mated female produces an average of 55 eggs in her lifetime. The lifecycle in the laboratory can vary from 3 days at 86 ºF to 20 days at 68 ºF. • High temperatures and low rainfall are ideal for development of large populations of parnicle rice mites in the field. • Continuous rice culture and the sharing of equipment between fields is also conducive to building damaging populations of the mites. • Feeding takes place behind the leaf sheath. • They also feed on developing panicles from the boot stage to the milk stage of heading. • During feeding, they inject toxic saliva. • The mites have been associated with sheath rot as well as bacterial panicle blight. The mites can carry sheath rot spores on their body. Revised during 2011

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The mites cause damage to plant tissue which may facilitate entry of fungal pathogens into developing grains and the leaf sheath. This damage to grains results in sterility and deformed grains, straight-head, and parrot-beaking of grains. Sugarcane Mites Oligonuchus indicus Tetranychidae:Acarina • It is a harmful pest of sugarcane, maize and sorghum. • This species is widely distributed in India. • The attack of this mite on sugarcane is more in north India and less in south India and causes 20-30% damage to the crop. • In case of sugarcane, maize and sorghum, feeding of this mite causes the appearance of reddish spots which increase with the severity of attack. • These spots later coalesce to form large red patches and spread on the leaf surface to turn the colour of the leaf red. • The leaves turn red in patches. It is grayish green mite with black blotches scattered over dorsum. There are 30 overlapping generation in a year; all stages occur together living in a delicate web of silk and breeding is continuous. • The mite spreads by wind and also by crawling from plant to plant, when leaves touch each other. • Adult males feed very little and the main damage is caused by the females and immature stages. • Soft leaf varieties of sugarcane are more susceptible to attack than those having hard leaves. • Red mite occurs in hot weather mostly in years when a few summer showers are received. • The white mite appears a little later in May, June and July. • It occurs under characteristic oval webbings and the chlorophyll is depleted in oval patches, wherein in severe cases are extensive. • Hot dry conditions favour their increase Cotton Red Spider Mite (Erra Nalli) Tetranychus telaries (Two Spotted Spider Mite) Tetranychus bioculatus Polyphagotarsonemus latus Eriophyes gossypii Tetranychidae : Acarina • The mite is a polyphagous and is known to feed on 183 species of plants including cucurbits, brinjal and bhendi on which it is sometimes very serious. • Mites are tiny, transparent and found mostly under the lower side of leaves. • Nymph is light brown in colour and has two eye spots. Four pairs of legs and quite active. Adult female body is oval and is variable in colour, red, green amber or rusty green and with two large pigmented spots on the body. Nature & Symptoms of damage: • Both nymphs and adults cause damage. • Large numbers of webs are formed. • Spider mites feed on the lower surface of the leaf underneath a web. • The infested leaves rapidly curl up, become hard and crisp and ultimately shed. • Bolls ripen prematurely and in serious infestation shed. • The large scale use of chlorinated hydrocarbon insecticides for the control of other pests leads to the multiplication of the mites as these are less toxic to mites but they kill their natural enemies in large number.

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Brinjal Red Spider Mite Tetranychus urticae Tetranychidae: Acarina • Highly polyphagous and has a world-wide distribution. • Among vegetables, brinjal, bhendi and bean are preferred mostly. • Adults are ovate, reddish brown with four pairs of legs. • Eggs are globular and whitish. • Larvae (1st instar nymphs) are pinkish with three pairs of legs while nymphs (later instars) are greenish-red, look like the larvae, but have four pairs of legs. • Life cycle is completed in about 20 days. • Red spider mites are found in large colonies on underside of leaves and protected by the silk webbing constructed by the female. • Leaves put forth a characteristic blotching appearance; become whitish then brown patches appear. Later the entire effected leaf become discolored and dried away. • Affected leaves gradually curl, get wrinkled and crumpled. • In heavy infestations, even fruits are affected. • More infestation occurs in warm and dry months. • Sulphur dust, or sprays of wettable sulphur 3-5g /litre, Ethion or Dicofol @ 3ml/litre of water are recommended. Chilli Mites Polyphagotarsonemus latus (Red Spider Mite/Broad Mites) Tarsonemidae:Acarina • Among the non-insect pests of agricultural crops, mites are probably the most notorious ones and gaining tremendous importance in the recent years due to their devastating nature. • In case of solanaceous vegetables, chillies are severely damaged by tarsonemid mite, Polyphagotarsonemus latus with yield loss up to 94% under favorable conditions. • Of late, mite has developed as a major problem in chilli cultivation. • It is making its appearance in the nursery itself after 40 days of sowing. • In the main field it gains spread during the month of November. • Nymphs and adults suck sap from leaves. • Affected leaves curl downward along the margins of the leaf and attain an inverted boat shape. • Leaf petioles elongated and small leaves serrated and looks like bunchy appearance. • Infestation at early flowering stage causes bud & flower shedding, leaf curling, twisting. Leaves turn to dark grey in colour and reduce leaf sheath, stops flowering, and leads to considerable yield reduction. • In severe cases fruit wall becomes hard and white strips appears on the fruit. • As the population increases, mites web profusely covering the foliage on all sides, thus resulting in poor growth of the crop. • Spray Phosalone (0.1%) @ 3ml/litre (Severe conditions) or Wettable sulphur 3g/litre of water or Dicofol (0.09%) @ 5ml/lit of water. Citrus Rust Mite Schizotetranychus hindustanicus Tetranychidae: Eriophyidae • These mites scrape the surface and suck sap causing large number of whitish spots. In each spot four or five mites may be seen. Even when mites disappear the whitish spots remain. • Spray Dimethoate 0.03% and there should be at least a fortnight interval between spraying and harvest. Or spray Wettable Sulphur 3-5 gms/lt of water.

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Mango Mite Paratetranychus manguferus • Among non-insect pests, mites are of importance. • They cause damage not only to growing trees but also at seedling stage. Coconut Eriophid Mite Aceria guerreronis Acarina:Eriophyidae • Mites remain underneath the periyanth (cap) and cause injury by feeding on the soft paranchymatic tissues. • Though the mites are microscopic their damage is enormous and hundreds of mites could be seen in each infested button and tender nut. • Visible symptoms are brown discoloration noticed in patches of the husk. • In case of severe attack the button sheds, resulting in very poor setting percentage. • In other cases the nuts are deformed and undersized with poor development of kernel and husk. • In severe cases, oil percentage also reduced. • The mites spread through wind and its multiplication is at a high rate. Though this pest was noticed only in a limited area during 1998 it has become a major pest of coconut in India. Tea Mites Red spider mite Oligonychus coffeae Scarlet mite Brevipalpus californicus Purple mite Calacarus carinatus (Pest of South India) Pink mite Acaphylla theae Yellow mite Polyphagotarsonemus latus • A red spider mite lays eggs adjacent to mid rib and veins. Eggs are laid one at a time ranging from 4 to 6 per day. Female oviposits over a month. • The red spider mite completes several generations in a year and females have the capacity to reproduce parthenogenetically i.e. without fertilization of eggs, producing male progeny. A female may live upto a month. • Red spider mites spin silken net over their colonies so that they can move underneath these webs protected from weather vagaries. • They move from one bush to the other by the silken thread, wind and by sticking to the body of animals and people who pass by the bush. • Increase in red spider mite population is mainly related to the dry season and rise in temperature during spring and early summer in North East India. • The mites attack the upper surface of mature leaves starting from the midrib and vein areas and gradually spread to the whole of the leaf. • The feeding causes the leaf to turn coppery-red coloured. Mites leave their cast skin and empty eggs as white spakes on the leaf surface. Heavy infestation leads to dropping of the leaf. • Factors like drought, un-prunned tea, sunny days, un-smooth leaf surface texture and dust accumulation allows easy proliferation of the mite population. Further the increase in mite population may be influenced by organic manuring, poor drainage and may be influenced by the weeds acting as alternate host in the plantation areas. • Natural enemies of red spider mites that ranges from Coccinellid to Neuropteran. Predatory mite Agistemus sp. Rove beetles also consume most of the life stages of red spider mite. • Spray dicofol 18EC 2 ml/lit or ethion 50 EC 2 ml/lit or monocrotophos 1ml/lit • Application of wettable sulphur 80 WP 2g/lit using hand operated sprayer.

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ACARICIDES: • Acaricides are pesticides that kill members of the Acarina group, which includes ticks and mites. They are also called as miticides (kills mites), and ixodicides (kills ticks). • Acaricides are used both in medicine and agriculture, although the desired selective toxicity differs between the two fields. Macrocyclic lactones Abamectin, Ivermectin Oragnochlorines DDT, Dicofol Carbamates Carbaryl, Carbofuron, Propoxur, Aldicarb Formamidine Chlordemiform, Amitraz Organophosphates Monocrotofos, Chlorpyrifos, Dimethoate, Ethion, formothion, parathion, phorate, Phosalone, triazophos Phenyl Pyrazole Fipronil Pyrethoids Cypermethrin, fluvalinate Unclassified Sulfur, propargite, tetradifon, Spiromesifen, bifenazite

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Mites Management: • Regular scouting is necessary to detect early infestations and also monitor the efficacy of control measures. Mites are small and difficult to see with naked eye. A crop scouting program includes the visual inspection. A 10x hand lens is a useful tool to detectmites on leaves. The mites, eggs and cast skins can be best seenby examining the under surface of the leaves. Appearance ofyellow spots on the upper surface of the leaves are also theindication of mite incidence. Mites can also be sampled using thebeat method whereby plant parts are beaten onto a white piece ofpaper or card. The dislodged mites from beaten plant parts can beseen then readily crawling on the paper. • Cultural method: Sanitation is to be maintained for eliminating the sources of the mite infestation. Plant debris is also a source of both immature and adult mites and they should be destroyed. Weedy farms are most likely to contain more mites. Hence weeds and alternate host plants inside and near the outside the farms should be removed. Spider mite outbreaks frequently occur where plants are dusty or stressed. Proper irrigation scheduling reduces the water stress and also increases the humidity thereby reducing the mite population. High volume with high pressure water sprays help to reduce the dust and water stress, increase the humidity and also dislodge the mites from foliage thereby temporarily reducing the mite populations. • Biological: Although some predators recorded in nature they do not play, significant role in keeping the heavy mite population buildup under check on grapes. The fungi Beauveria bassiana, Verticillium lecanii, Hirsutella thompsonii and Pacilomyces fumosoroseus are known to cause mortality in mites. These fungal pathogens can be used in the management of spider mites on grapevine. • Botanical Pesticides: Different neem formulations containing azadirachtin depending upon the strength of botanical viz., 1% @ 2.0 ml and 5% @ 0.5 ml/l can be sprayed. • Chemical Control: Effective management of mites on crops relies primarily on the use of chemicals. Time of application is crucial in the management of mites. First application should be made on the appearance of mites. Several old and new molecules are available for the control of mites. They can be used in the non-cropping season. List of chemicals generally recommended for various types of mites in different crops. Dicofol 18.5EC @ 2.5ml/L Wettable Sulphur 80WP @ 2.0g/L Azadirachtin 1% @ 2.0ml/L Abamectin 1.9EC @ 0.3ml/L Fenpyroximate 5SC @ 1.0ml/L Difenthiuron 50SC @ 1.0ml/L


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Sulfur: • Sulfur is a non-systemic contact and protectant fungicide with secondary acaricidal activity. • It is usually formulated as a dust (90%D), with up to 10% inert material to prevent balling. • Dust flow can be increased by the addition of 3% tricalcium phosphate. • It is also formulated as a wettable powder (80%WP), and is recommended @ 2.0-2.5 kg formulation/ha or 2g/lit as per requirement. • Thiovit 80%WP (Syngenta), Sulfex 80%WP (Excel), Dicofol: • Persistant organochlorine acaricide od moderate mammalian toxicity • Metabolic product of DDT • Kelthane 18.5%EC and Kelthane 50WP (Dow Agro) is available in market. • Non-systemic • Recommended @ 0.5-2.0 kg ai/ha • Broad-spectrum miticide Propargite: (Omite 30%WS-Chemtura chemicals) • Omite® miticide has been a valuable part of tree and vine crop production for over 30 years. While a few mites won't create economic damage, they can be an indication of things to come. Mite populations can explode in a short time, and if millions of mites are left to feed untreated, the destruction can approach catastrophic proportions, result in reduced yields at harvest. • When applied according to label directions, it keeps mite populations below damaging levels. Omite controls a broad spectrum of mite species while being easy on beneficial insects and mite predators. • Omite miticide fits IPM programs and controls mites resistant to other miticides. • Omite gives long residual activity with a combination of chemical and natural control and is more economical to use than most other miticide products. • It is compatible with many other pesticides • Omite is not systemic in action; therefore, coverage of both upper and lower leaf surfaces and fruit is necessary for effective control. Formamidines: (Chlordimeform, Amitraz) • A new group of acaricidal insecticidal compounds, used as plant sprays and topically on animals. • Examples: Chlordimeform (CDM), Amitraz (Mitaban 19%EC, Preventic 19%EC) • Their biological activity and uses are defined by their toxicity to spider mites, ticks, and certain insects and they are particularly effective against juvenile and resistant forms of these organisms. • Mode of action: Although many reported underlying biochemical mechanism, including inhibition of monoamine oxidase activity, uncoupling of respiration and blockade of neuromuscular transmission. Recently, interaction with octopamine receptors in the central nervous system is also reported. • Amitraz: on animals it is used to control ticks, mites, lice and other animal pests. Very popular veterinary drug. Ketoenols: (Spiromesifen -Oberon 240SC-Bayer) • Very unique mode of action through inhibition of lipid bio-synthesis and acetyl- CoAcarboxylase. • Non-systemic acaricide with translaminar action. • Stomach poison with some contact action. • Effects egg and immature stages of mites. • Registered for use in India during 2009.


Lecture 47: (PHYTOPARASITIC NEMATODES) 47. Phytoparasitic nematodes-brief morphology and systematics-important phytophagous nematodes in rice (white tip nematode), wheat (cyst and gall nematode), vegetable (root knot nematode), citrus (citrus nematode) and banana (burrowing nematode) and their management.

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Depending on the species, a nematode may be beneficial or detrimental to plant health. From agricultural and horticulture perspectives, there are two categories of nematode: predatory ones, which will kill garden pests like cutworms, and pest nematodes, like the root-knot nematode, which attack plants and those that act as vectors spreading plant viruses between crop plants. Plant Parasitic nematodes: The important parasitic nematodes are: Rice Ufra disease Ditylenchus angustus Rice White tip disease Aphelenchoides besseyi Potato Root Knot disease Ditylenchus destructor Potato Cyst nematode Globodera rostochinensis Wheat Ear cockle Auguina tritici Wheat & Barley Molya disease Heterodera avenae Cucumber, Tomato Root Knot nematode Meloidogyne incognita Tobacco, Sugarcane, Root Knot nematode Meloidogyne javanka Banana, Vegetables Banana Rhizome rot Radopholus similis Citrus Slow decline Tylenchulus semipenetrans Pepper Slow Wilt Radopholus similis Cotton, Maize, Banana, Reniform nematode Rotylenchus reniformis Pulses Coffee Root lesion Pretylenchus coffeae Revised during 2011

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Nematodes are simple roundworms. Colorless, unsegmented, and lacking appendages. Nematodes may be free-living, predaceous, or parasitic. Many of the parasitic species cause important diseases of plants, animals, and humans. Plant parasitic (Phytophagous-harmful) and insect parasitic (Entomopathogenicbeneficial) nematodes are important to understand in crop protection. Nematodes are structurally simple organisms. Adult nematodes are comprised of approximately 1,000 somatic cells, and potentially hundreds of cells associated with the reproductive system. Nematodes have been characterized as a tube within a tube: referring to the alimentary canal which extends from the mouth on the anterior end, to the anus located near the tail. Nematodes possess digestive, nervous, excretory, and reproductive systems, but lack a discrete circulatory or respiratory system. In size they range from 0.3 mm to over 8 meters.

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Virus transmitting nematodes: Longidorus macrosoma transmits prunus necrotic ring spot virus Xiphinema americanum transmits tabacco ring spot virus. Paratrichadorus teres transmits pea early browning virus. Trichodorus similis transmits tobacco rattle virus.

RICE WHITE TIP NEMATODE (leaf nematode) Aphelenchoides besseyi • This is one of the economically important nematode parasite infecting rice crops throughout the world. This nematode was first reported on rice from Japan, and an extensive work has been carried out on this nematode pest. • Feeding at leaf tips in rice results in whitening of the top 3-5 cm of the leaf, leading to necrosis known as "White Tip". There is also distortion of the flag leaf that encloses the panicle. Diseased plants are stunted, lack vigor and produce small panicles. Affected panicles show high sterility, distorted glumes and small and distorted kernels. In the seed-bed, emergence of severely infected seedlings is delayed and germination is low. The most conspicuous symptoms occur at the tillering stage. • Management: Aphelenchoides besseyi infestations can be avoided by using nematodefree seeds and planting in nematode-free planting material. Destruction of infected source of inoculum like seeds,weeds,debris left after harvest in field. Chemical treatments of seed with benomyl or thiabendazole have also been reported as being effective in controlling A. besseyi. Spraying of infested crop with Parathion (.025%) and Trichlorophos (0.03%) three times has been found to be effective.

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ROOT KNOT NEMATODE (Vegetables) Meloidogyne incognita Meloidogyne javanica • Root Knot Nematode (RKN) is a serious malady in tomato and other vegetables. • The functional root system is modified into galls and it impairs uptake of water and nutrients. Poor development of root system makes the plant highly susceptible to drought.

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WHEAT CYST & GALL NEMATODE Heterodera avenae (Cereal Cyst nematode-Molya disease) Heterodera zeae • Symptoms: Cereal cyst nematodes are more readily detected on the roots of seedlings than on adult plants. The roots of infested plants develop frequent branches and swellings (cysts). Seedlings weakened by nematodes often are invaded by soil-borne pathogens, especially root and crown rots. Below-ground symptoms include increased root production such that roots have a “bushy knotted” appearance. Above-ground symptoms appear early in the season as pale green patches, with lower leaves of the plant being yellow, and a reduction in tillers.


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Management: • Crop rotation with non-host crops: Tomato when rotated with non-host plants like cereals, onion, crucifers, groundnut and cotton reduces the nematode population. • Inter-cropping: Mustard, asparagus, sesamum, marigold and red gram when intercropped with tomato act as deterrents for RKN through their root exudates. Crotolaria and cowpea allow the larvae to enter into their roots. But after entry, larvae will be immobilized and further development into adult will be arrested. • Deep summer ploughing: During summer, soil should be ploughed and exposed to sun. • Crop sanitation: The roots of affected crop should be burnt. • Mulching: Use of polythene mulches during summer increases soil temperature, which is unfavourable for nematodes. • Flooding the land for more than one-week leads to asphyxiation and death of nematodes. • Soil application of neem or karanji oil cakes (2t/ha) or saw dust (2.5t/ha) can also be practiced • When the crop is grown under greenhouse conditions, steam sterilisation of soil is also effective. • Fertilisers like calcium cyanide, sodium cyanide and urea cyanamide can release ammonia and NH4, which is poisonous for nematodes. Seed treatment with Aldicarb or Carbofuran (2gm/Kg) or nursery treatment (2gm/m²) or seedling root dip (1000 Revised during 2011

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In addition, RKN in association with pseudomonas leads to bacterial wilt, which in association with soil borne rhizoctonia reduce seed germination and increases root rot problem Nematodes live in the soil and feed on root juices of plants, causing small swellings known as root knots or galls. The female deposits eggs in or on the roots, or in decaying root debris. The juveniles hatch from the eggs and move toward root tips or minor wounds. They feed on root tissue. All stages of plant growth are attacked. Aboveground symptoms often develop slowly over time and may go unnoticed until plants are well developed. Symptoms consist of stunting, yellowing and a general unthrifty appearance of plants. Infested plants may wilt or die in hot, dry weather. Belowground, the roots will have obvious galls or knot-like swellings. These swellings prevent movement of water and nutrients to the rest of the plant resulting in stunted plant growth. Plants affected by root-knot nematodes are more easily infected by soil-borne diseases caused by Ralstonia solanacearum (bacterial wilt), Sclerotium rolfsii (southern blight) Fusarium, Pythium, or Rhizoctonia. This secondary infection may lead to extensive discoloration of internal stem and root tissue, and rapid plant death.

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mg/L) for 30 minutes or main field application of chemicals (2Kg/ha) controls the nematode efficiently. VAM fungus is proved to reduce the number of nematodes that develop into adults. Fungus paecilomyces lilacinus can attack the eggs of nematode when applied at 8 gm/plant

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Telynchulus semipenetrans

Infestation of nematodes is one of the main factors responsible for slow decline of citrus. Damage caused by a citrus nematode infestation depends on the age and vigor of the tree, density of the nematode population, and susceptibility of the rootstock. Mature trees can tolerate a considerable number of these nematodes before showing lack of vigor and decline symptoms. In heavily infested sites, young trees may be stunted or fruit production may be reduced on bearing trees that have susceptible rootstocks. The damage is greater when trees are predisposed by other factors such as Phytophthora root rot and water stress. Symptoms of nematode damage above the ground are lack of vigor, twig dieback, decline in growth, and reduced fruit size and yield. Nematode infestations may occur without inducing any aboveground symptoms. Underground symptoms of citrus nematode infestation include poor growth of feeder roots and soil adhering to roots giving them a dirty appearance. Management: Good sanitation practices are essential to avoid nematode infestations. Use certified nematode-free material for planting. Crop rotation with annual crops for 1 to 3 years before replanting citrus helps to reduce citrus nematode populations. Using a resistant rootstock is recommended whether or not nematodes are present. Trifoliate orange is known to be tolerant to citrus nematode. Soil application of Neem cake and chemicals like Temic 10G (4 kg a.i./ha) are used successfully to control the nematodes. Intercropping of Marigold has repellent action and reduces the population of nematodes in citrus.

BANANA BURROWING NEMATODE Radopholus similis

Management of nematode diseases • Crop rotation: The susceptible crops should be rotated with non-susceptible crops to eliminate or reduce nematode population. Heterodera, Globodera & Meloidogyne does not survive in soil for long time & hence they can be controlled by proper crop rotation. • Clean Seed: Angunia tritici galls are found mixed with wheat seed. Seeds should be cleaned & the galls should be eliminated. • Cleaning of farm implements: Nematodes do not move more than a few inches a year of their own accord & most spread is passive. The infested soil sticking on the farm implements should be cleaned before taking them to new field. Revised during 2011

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The first symptom of the disease is a small dark spot on the root. The nematode deposit eggs in the root tissue. Larvae after hatching form the eggs feed on the root tissue. Fungi rapidly invade such damaged root tissue. The number of fruits in the bunch is reduced and individual fruits are small. Affected plants do not respond to fertilizers, irrigation or cultural practices. Nematode population is built up rapidly in ratoon crops. Management: Application of Carbofuran 3G or Phorate 10G @10 g/pit at the time of planting or application of neem cake (250-400 g/pit) at the time of planting reduces the pest population. Control measures such as application of nematicides to the growing infected plants and planting of nematode-free corms in fallow soil are recommended. Recently granular nematicides are becoming popular. They are easy to apply by hand to the soil around the mat at times combined with fertilizers. Some have systemic action. They are carried down into the soil by rain or irrigation water. Three applications of Nemacur (Phenamiphos) are effective in controlling the nematodes

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Selection of healthy propagating material: Banana rhizome rot nematode spreads through suckers. Hence healthy suckers alone should be used. Organic Manures: Organic manures enhance nematophagous fungi & antogonistic bacteria & hence reduce the nematode infection. Enemy plants: Root exudates of some plants are inhibitory to nematodes. They are called enemy plants. Tagets erecta reduces pratylenchus infection. Asparagus reduces Paratrichodorus, christiei crotoloria reduces Meloidogyne population. White mustard reduces potato cyst nematode. The enemy plants can be grown as an alternate crop or as an intercrop. Intercropping will be more beneficial. Trap cropping: Oats is an efficient trap crop for Heterodern avenae which attacks wheat & barley. Oats is ploughed in before the nematodes mature. Biological control: Many nematophagous fungi have been reported. Pseudomonas is antagonistic to the nematodes. Virus infection in Meloidogyne incognita has been reported. Amoeboid organisms attack larvae of potato cyst nematode. Huge amount of organic matter is essential to activate these biological agents for control of nematode diseases. Physical methods: The infested soil can be sterilized with steam. Potato cyst nematodes are killed by passing the steam into the soil thro' perforated pipes in western countries. Hot water treatment will be useful to control cyst nematodes in potato tubers. Rice white tip nematode can be eliminated by hot water treatment. Chemical control: Many fumigants are available to control nematodes. Methyl bromide (Dowfume MC-2) at 400-900 kg/ha, dichloropropene (Telone) at 500-900 kg/ha, dibromochloro propane, (Nemagon) at 120 kg/ha & metham – sodium (vapam) are useful. Some of the granules also reduce nematode population. Aldicarb (Temik) at 11kg/ha & Oxamyl (vydate) at 11kg/ha effectively control nematode. Carbofuran 0.751.0 kg/ha also reduces nematodes. Resistant varieties have been developed against many nematodes. Quarantine: Potato cyst nematode is a quarantine objective & strict quarantine prevents the movement of the nematode from one country to another.

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Beneficial Nematodes (Entomopathogenic Nematodes): • The only insect-parasitic nematodes possessing an optimal balance of biological control attributes are entomopathogenic or insecticidal nematodes in the genera Steinernema and Heterorhabditis. • Entomopathogenic nematodes are extraordinarily lethal to many important insect pests, yet are safe for plants and animals. This high degree of safety means that unlike chemicals, or even Bacillus thuringiensis, nematode applications do not require masks or other safety equipment; and re-entry time, residues, groundwater contamination, chemical trespass, and pollinators are not issues. Most biologicals require days or weeks to kill, yet nematodes, working with their symbiotic bacteria, can kill insects within 24-48 hours. Dozens of different insect pests are susceptible to infection, yet no adverse effects have been shown against beneficial insects or other nontargets in field studies.Nematodes are amenable to mass production and do not require specialized application equipment as they are compatible with standard agrochemical equipment, including various sprayers (e.g., backpack, pressurized, mist, electrostatic, fan, and aerial) and irrigation systems.


Lecture 48: (RODENTS AND BIRDS) 48. Rodents (infesting field and storage) and birds-nature and symptoms of damage and management of rodents and birds.

RODENTS (Field Rats & Commensal Rats)

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Millardia meltada Bandicota bengalensis Muridae : Rodenta : Class : Mammalia Soft furred field rat or grass rat Millardia meltada • It occurs in irrigated fields but observed in pastures also. • It is nocturnal and lives in simple burrows. • It breeds throughout the year with litter size of 2-10 young ones. • It is small and slender. Adult weight 100 gm. Total length including tail 19-29 cm, tail 9-14 cm either equal or little shorter than head and body, moderately to poorly haired. The tail is dark above and pale below. Indian Mole Rat or Lesser Bandicoot Rat Bandicota bengalenses • It is an excellent swimmer, often living in flooded rice fields and bunds. • Also occurs in the wheat crop fields and godowns. • It is nocturnal and fossolial. • Hoards large amounts of food in its burrows. • Breeds commonly twice a year with 8-10 young oens in each litter. • Adult weight 325 gm. Length from nose to tip of tail 36-48 cm. Tail 18-20 cm; less than some times equal to length of head and body together, 160-170 rings clearly seen on scaly tail. Ear 2.5 to 2.6 cm in length, thick and opaque. Snout – short, stumpy, pig like. Fur and colour – thick, short and harsh, spenes present, dark brown, pale brown or reddish above. • Droppings: Scattered, oval weighing 0.042 gm. • It is widely distributed in India. Lesser bandicoot Grass rat Bandicota bengalenses Millardia meltada • Larger in size. • Smaller in size • Dark greyish in colour with a greyish white belly • Dark brownish grey above and and a bare tail pale grey below with soft fur • It makes larger ramifying burrows in soil • The burrows of this are similar to extending to a depth of 1-1.5 m and laterally 9-12 that of the mole rat excepting m. There are 4 or 5 openings for the burrow; the that they are smaller in length entrances are protected by heaps of excavated and usually more than one adult soil. It usually live alone one in a burrow rat occupies a single burrow Nature and Symptoms of damage • Rodents attack rice at all stages of growth from planting to harvest and if there is opportunity, even they will continue to attack the grain in store. • Freshly sown may be dug up and the seed may be eaten. • Rats also feed on germinating grains, cut and feeds on tender seedlings and also grown up plants in boot leaf stage. • On young rice plants, rodents attack the heart of the stem discarding the leaves. The rodents make the rice stems fall. • Some rodent species may store grain in their burrows. • Large rodents, besides feeding on the cop may cause serious damage to the bunds.

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FIELD RATS:


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COMMENSEL RODENTS House rat or black rat Rattus rattus House mouse Mus musculus Common Indian field mouse Mus musculusbooduga Brown rat Rattus norvegicus Muridae : Rodentia • Its habit of preying on man’s food and on his waste products drives them to entire human habits but they do not remain or rest there. • Commensal rodents: Living on man but not with man.

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Control Measures • Rodent pest management envisages using of poison baiting with zinc phosphide followed by fumigation of residual freshly opened burrow openings with aluminium phosphide tablets (Celphos, quickphos, phosfuma etc.,) for control of rodents in crop fields and threshing floors. • This should be planned to cover a larger area. This minimizes reinfestation in the cleared area from surrounding infested region, if any. • Rodent control operation should be taken up before sowing of the crop. • The rodent burrows should be marked and the burrow opening closed with moist soil and tagged with flags. • The burrows opened out on the next day are active burrows or live burrows. • Then pre-baiting has to be done on the 1st and 3rd day. • On 5th day 2% zinc phosphide is added and baits distributed 70-80% kill of rodent population can be secured by the operation. • The remaining population can be controlled by fumigating burrows. • On 6th day all burrow openings are closed. • On 7th day in those reopened burrows aluminium phosphide @ 1.5 gm/ active burrow opening are placed and this will take care of residue rodent population. In Households (single dose poisoning-without baiting): The following mixture may be prepared, and offered to kill the rodents: 1. Crushed wheat, maize, bajra etc 450 gr 2. Sugar 15 gr 3. Edible Oil 10 gr 4. Anticoagulant 25 gr Zinc Phosphide bait formulation For Pre baiting Cereal floor 97 parts Vegetable Oil 3 parts or Whole/cracked grain 98 parts Vegetable Oil 2 parts 8 grams of the above mixture per active burrow should be placed After two days of Pre baiting Cereal floor 95 parts Vegetable Oil 3 parts Zinc phosphide 2 parts or Whole/cracked grains 96 parts Vegetable Oil 2 parts Zinc phosphide 2 parts 8 grams of the above mixture per active burrow should be placed

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House mouse Mus musoulus • It is quick, tends to nibble and run rather than stay longer at food source. They can pass through a hole slightly less than ½". • They live mostly in houses. • 6-10 litter per year with 6-10 young ones per litter. • They can climb easily but can swim when necessary. • Distributed all over India. • Omminovorous. • Total length including tail 8-22 cm with pointed snout. • Brownish grey above and whitish to light grey on belly. House rat Rattus rattus • Lives in close association with human beings. • Excellent climber and good swimmer. • 4-6 letters / year and tail length 31-43 cm with pointed snout. • Dark brownish above (dorsal) and dirty white on belly. Brown rat or Norway rat Rattus norvegicus • Closely associated with the activity of man. • Good climber and swimmer. • Prefers wet or damp locations. • Do not close the burrow openings. • Length from nose to tail 35-41 cm with blunt snout. • Brownish above, white on belly. • These three species are known as commensal rodents. • They contaminate 20 times the material actually they eat. • A rat urinates 15-25 ml/day and 25-150 pellet droppings play / rat. • Regularly shed hairs @ 100-200 hair fragments per day/rat. • They bite sometimes human beings. • They spread disease. • They are social animal. • They share same food source and common run way. • They live closely to one another. • They are most active at dusk and during calm period. • Rats become conditioned to eating a particular food suspicious in nature. • Taste the food cautiously. • Develop bait shyness. • House mouse is not suspicious of new food. • Eagerly tastes all. • In single might mice tastes and feed on many different foods, hence difficult to get them to take a lethal dose of poisoned bait. • Mice readily accept water baits. Control Measures for commensal rodents • Killing rats by sticks • Trapping the rats using traps. • Snap neck trap kills the rat instantly. • Live catch traps trap the rats alive Eg. Single rat trap, wonder trap. • Chemicals: Acute poisons (zinc phosphide), Anticoagulants (warfarins)

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Rodafarin C of solid baits: blood vessels break and rodafarin S liquid baits: mouse, month and arms death by hemorrhage. House rat and house mouse die after 2-5 days of continuous feeding. One measure of sodafairno S + 19 measures of water. Rodafarin C-1 part, granulated sugar-1part; vegetable oil-1part crushed grain of corn meal 17 parts. Acute poison: 2% zinc phosphide 3-5 groundnut oil is added in the bait. 95% flour + 1 to 2% zinc phosphide + 2% groundnut oil + 1% sugar (prebaiting for 2-3 days and then the bait is mixed with zind phosphide Fumigants : Aluminium phosphide (CP) solid, Ethelen difromide (EDD), Ethelene dichloride, carbontetra chloride (ED/CT) Natural enemies: Cats, dogs, owl, howks and snakes

BIRDS (As per the information and recommendations given by Dr. V. Vasudeva Rao, Network Coordinator, AINP on Agricultural Ornithology, Hyderabad) Crop losses due to the depredatory birds can occur either due to one species (parakeet) as in Subflower or a community of bord complex as in Pearlmillet, Sorghum, Paddy, Groundnut and Apple. Negative impact of birds on Agricultural Crops vary from region to region, season to season, depending on number of factors like number of depredatory birds, species complex, their food habits, cropping system etc. Almost all cereals, pulses, oilseeds, and several vegetable crops were susceptible to bird damage during sowing, seedling stage and ripening stage. Birds attracted to fruits at maturing and ripening stage. The cereals were more susceptible to bird attack during dough stage. Damage to crops of smaller grains such as sorghum, pearlmillet is more serious compared to that of lage sized grains (maize). Small cereal grains were preferred by both small and large size birds, whereas, maize is depredated primarily by large species such as parakeets and crows. Similarly, early and late maturing fields are more vulnerable to bird damage. Due to intensive farming, many species of birds obtain food from the agricultural fields throughout the year. Moreover, a few species viz. Roseringed Parakeet, House Sparrow, Weavers, Munias, and Doves manage to nest in close proximity to agricultural fields. Blue Rock Pigeons Roce Ringed Parakeet House Crow House Sparrow Black Drongo Indian Blue Peafowl Common Mynah

Columbia livia Psittacula krameri Coryus splendens Passer domesticus Dicrurus macrocersus Pavo cristatus Acidotheres thristis thristis

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Birds are known to cause damage to Pearlmillet, Wheat, Paddy, Sorhum, Maize, Sunflower, Oil Palm, Groundnut, Safflower, Apple, Kinnow, Date Palm, Banana, Pomegranate, GuavaGrapes, Papaya etc.


Stages of Maize crop vulnerable to Bird damage Stage

Species involved Type of damage

Sown Seed

Pigeon and House crow

Disturbance of sown and soaked seeds and feeding on them.

Germinating Stage

House crow

Young seedlings are damaged. Aerial portion discarded feeding on the remaining food material present in the seed.

Cob emerging Stage

Rose ringed parakeet

Emerging tender cobs are damaged along with the silky style and green tender spathe(husk)

Milky stage

Roseringed parakeet

Green spathe (husk) is cut into pieces and the cobs are partially exposed and the grains are damaged by feeding on the milky contents.

Dough stage

Roseringed parakeet

The exposed tender grains are removed and fed

Mature stage

Roseringed parakeet, House crow

Green spathe dries up, and the husk is pulled out. The cobs are fully exposed. Grains are fed and cause total damage of the cob.

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Parakeet damage on Saunflower Symptoms of damage: • The bird’s damage starts from the milky stage and continues till harvest. • These consumes on an average of 152 seeds/day. Management • Establishment of scare crows in the field so as to distract the birds. • Bursting of crackers and carbide guns, tying polythene bags. • Use of bird scaring tape (reflective ribbon or bird scaring ribbon). • Using bio-acoustic method like pre-recorded distress calls to distract the birds. • Destruction of bird nest in and around the field. • Deploy two labourers per hectare to scare away the birds. • Pruning of perching and breeding places • Spraying of neem kernal powder solution at 10 g/litre of water after seed shedding repels the birds. • Use of bird proof nets.


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General Depredatory Bird Pests Management Practices: Damages inflicted by harmful birds can be reduced using a variety of methods which can be categorised as lethal and non-lethal methods. Lethal methods • Lethal methods involve killing of birds, shooting, trapping, fumigation, poison baiting, egg and nest destruction, etc. In past, lethal methods were extensively used to control bird pests in India and elsewhere because killing was considered to be the surest way of getting rid of harmful birds. • Killing of any bird species is now illegal in India and also not approved by the public. In view of the above facts, lethal methods of bird management are not recommended these days. Non-lethal methods • They do not involve killing of birds but instead aim at repelling them from their preferred crops fields. As a result of successful repelling, the damage gets distributed over larger areas and thus no longer remains an economic injury. • If alternative foods of the concerned species are available, a part of the bird pressure may shift to such foods which would reduce the total damage to the preferred crop. Non-lethal methods include habitat manipulation, the use of repellents and provision of alternative food to pest bird species Wrapping method in Maize Crop • Covering maize cobs by wrapping adjacent green leaves around them reduce bird damage to negligible level by Parakeet and Crows, which were the major problematic birds. • Being hidden and camouflaged, the wrapped cobs escape detection by birds, and thus the crop is protected. All cobs need not to be covered, but covering border rows cobs, and randomly the middle rows cobs is effective. Habitat manipulation • Bird damage is known to be higher in crops nearer to bird preferred habitats. • Habitat manipulation involves removing roosting, nesting and feeding sites or food and shelter from the preferred habitats of harmful birds.

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Bird damage to Oilpalm • Many birds such as the forest crow, the house crow and the common Indian myna cause severe damage to oil palm fruit bunches. • These birds feed on the mesocarp of the oil palm fruits. • The damage can be minimized by scaring the birds and covering the ripe bunch with wire net, 150 days after fruit set. Management of Avian pests in Oilpalm • Bunch covering: Covering the fruit bunch with suitable low cost material is the simplest and effective method • Wire net covering: Twenty two gauge galvanized iron wire mesh (60x90 cm) (the size depending upon the fruit bunches) used to cover the Fresh Fruit Bunches (FFB) at least of 3-4 times. At least 10 cm gap between the net and the fruit bunch. • Oil Palm leaf covering: Old palm leaves-used for covering fruit bunches to protect them from avian pest. Leaf tips of about one meter length are cut and packed at close intervals into the leaf axils. Near the fruit bunches and tied with rope to keep them firm and impenetrable by the bird. Other materials like plaited coconut leaf basket, reed basket, used polythene (cement) bags etc.


The idea is to make these habitats less attractive for birds so that the damages to the adjoining crops may be reduced. Repellents • Substances and devices that cause pest species to avoid the otherwise attrative or palatable materials are called repellents. • Bird repellents include several types viz., visual, auditory, chemical plant-based and physical. Visual repellents • Visual repellents like scare crows have been used in India since ages. • The most promising visual bird repellent known so far is the reflecting tape/ reflective ribbon, which is a polypropylene metallic shining tape (11 mm wide, 0.025 mm thick, with one side red and the other silver) that reflects sunlight causing flashing effect and produces a humming noise in wind, thereby scaring birds. • It is stretched between poles (with 2-4 twists per 30 m length and enough slack to allow undulation) 0.5-1.0 m above the crop, in parallel rows, keeping row to row distance at 3-5 meters. • Bairds like Roseringed Parakeet, House Crow and Mynahs are easily evaded with this technique in crops like Sunflower, Maize, Sorghum, Pearlmillet and Orchards. Auditory repellents (Bioacoustics etc.) • In India and several other countries, birds have been traditionally scared by producing noise orally, with fire-crackers or by beating drums and empty cans. • Automatic acetylene exploders or bird-scaring guns that produce a loud exploding noise periodically have been used to scare birds in some parts of India. • All noise producing devices have a major draw-back i.e. birds get used to them quickly. • Boradcasting of distress calls of depredatory birds keep birds away. Chemical repellents • Many chemicals when used as seed dressings, sprays or dusts effectively repel birds from crops, thereby reducing bird damage. • Spraying of botanical formulation like Bio-Bird Repellent (BBR) and Fortune Aza (Neem Formulation) in fields reduce bird damage. • Seed treatments with Methiocarb [4(methylthio) 3,5-xylyl-N-methyl carbamate] has been found effective in reducing damage by weaver birds and sparrows to sprouting maize. • Thiram (retramethylthiuram sulphide), a fungicide, protects sprouting maize from crows. Alternative food • Availability of alternative food is an important factor in determining bird damage to commercial crops. • Generally, a scaring technique is more effective if alternative food is available to bird species being scared away. Screen Crop • Thick planting of sorghum (fodder crop) as well as maize significantly reduce Parakeet activity and damage in Maize crop grown for grain purpose. Lure Crop • Growing of fodder sorghum near the pearlmillet reduce bird damage.

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Notes: