Model based estimation of turmeric yield response to saline groundwater irrigation T. Kizza1, M. Sekhar2, S. M. Rao 2 L. Ruiz3 1.NARO, Mukono ZARDI ,P.O Box 164 Mukono Uganda;
[email protected] 2.Department of civil engineering , Indian Institute of Science,560012 Bangalore India 3.Institut National de la Recherche Agronomique, INRA I. Introduction World agricultural productions are in many areas below the expected potentials with a maximum recorded relative yield under irrigation at 71%,[1]. There are many causes of the low yields among them salinity. A study was carried out to assess the impact of irrigation water salinity on soil salinity and turmeric (curcuma longa) crop yield. Turmeric was reported by [2] as sensitive to saline soil and saline water irrigation. All farmers in the study area were irrigating with groundwater of unknown quality.
IV. Conclusions
III. Results
Fig.2. Electrical conductivities at the 95 tube wells
ECiw at watershed scale is presented in Figure 2..
Simulated yield (Fig.3) was in close agreement with expected yield from local data reported as 7.2t/ha .
The study was therefore preceded with watershed mapping of groundwater salinity levels using water samples from 95 randomly selected tube wells Fig.1
Fig.1 Berambadi WS showing tube wells
Significant (p≤0.05) interaction between ECiw and ECe and between relative yield and ECe.R2=0.686 (Fig.4) .
Many farmers are unknowingly losing crop yield to irrigation related salinity. We recommend groundwater quality mapping to aid decision making in control of irrigation related salinisation. The basis of characterizing water as safe for agriculture in a given location should be specific about crop and soil type to which the safety standard applies.
Fig.3. Histogram indicating the simulated yields
Further information
Fig.4 .A plot of relative yield Vs soil salinity
Other biotic and abiotic stresses were apparent on some plots causing interruptions in the trends. as also observed by [1].
The scatter plot of irrigation water salinity against soil salinity though significant indicated wide scatter. This could have resulted from different soil textures at the sites and the variation in number of years and cropping cycles of the farmers.
Relative yield against soil salinity 80
A monotonically increasing yield gap; range 2.1 t/ha (At ECe= 0.84 dS/m) to 5.7t/ha ( At ECe = 2.1dS/m) was observed.
II. Materials and methods [1.]Site selection :Twelve
sites with varying groundwater salinity levels were selected
[2].Field data collection: on plant performance [3] Potential yield estimation Using STICS crop model [3] [4] Laboratory soil and water analyses.
Literature cited 1. Lobell,D. B., Kenneth G. C. and Christopher B.( 2009). Field Crop yield gaps; their importance, magnitude and causes. Annual review of Environment and resource. 34, paper 3 2. Ravindran, P. N.,Nirmal Babu, K., Sivaraman, K.(2007). Turmeric : the genus Curcuma. ISBN
Relative yield(%)
70 60 50 40 30
y = -36.104x + 96.69 R² = 0.6863
20 10 0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 Ece (dS/m)
9780849370342 - CAT# 7034 . 3. Sreelash,K. Sekhar ,M., Laurent Ruiz , Samuel Buis and Bandyopadhyay, s.(2012). Improved Modeling of Groundwater Recharge in Agricultural Watersheds Using a Combination of Crop Model and Remote Sensing
Acknowledgments 1. The study was funded by CEFIPRA through AICHA project and the Indo-French Cell for Water Sciences 2. Water Education foundation sponsorship towards conference registration was appreciated 3. Purrington poster design was adapted
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