Hroceedings P ost suitability of the of H Oawaiian miodes continuatalis Entomological Society (2011) 43:67
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New Records and Accounts First Report of Trichogramma achaeae (Hymenoptera: Trichogrammatidae) from Hawaii 1
Mark G. Wright1 and Richard Stouthamer2
Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa 3050 Maile Way, Honolulu, HI 96822, USA; e-mail:
[email protected] 2 Department of Entomology, University of California, Riverside, CA, USA
Abstract. Trichogramma achaeae is reported from Oahu and Kauai. This egg parasitoid was first found parasitizing eggs of Helicoverpa zea on corn plants on Oahu. It was subsequently reared from on Lycaenidae and Noctuidae collected from Fabaceae and Euphorbiaceae respectively, on Kauai. Key words: Trichogramma achaeae (syn. achaea), Hawaii new state record During surveys of natural enemies of Helicoverpa zea (Lepidoptera: Noctuidae) in parent seed corn (Zea mays) production fields on the north shore of Oahu (Waialua area), a significant proportion of eggs collected from corn silks were observed to be parasitized. Eggs displayed typical characteristics of eggs parasitized by Trichogramma species. The eggs assumed a shiny black appearance instead of undergoing normal larval development (Hoffman et al. 2002). Individual H. zea eggs were placed into size 0 gel caps and held in the laboratory until emergence of wasps. Emerging wasps were submitted (to Dr. John Pinto, UC Riverside) for identification by examination of morphological characters. The wasps were identified as Trichogramma achaeae (syn. Trichogramma achaea) Nagaraja and Nagarkatti 1970. Genomic DNA was extracted for sequencing of the ITS2 gene (Stouthamer et al. 1999) and the ITS2 sequence was deposited in GenBank (accession numbers: MW07-1 JN872294; HT09-1 JN872295, HT20-1 JN872296) to facilitate molecular characterization of future samples. Parasitism of H. zea eggs by T. achaeae could exceed 60%, sometimes even in cornfields subjected to insecticide applications. Trichogramma achaeae were further reared from eggs of Lycaenidae collected from various Fabaceae on Kauai, and from eggs of Achaea janata (Noctuidae) collected from castor bean (Ricinus communis) on Kauai. The native range of T. achaeae is Asia (China, India, Russia); it has been purposefully introduced to various European countries and South- and Central American countries (Polaszek 2010). This appears to be the first record of this species from Lycaenidae hosts. Literature cited
Hoffmann, M.P., M.G. Wright, S.A. Pitcher, and J. Gardner. 2002. Inoculative releases of Trichogramma ostriniae (Hymenoptera: Trichogrammatidae) for suppression of Ostrinia nubilalis in sweet corn: field biology and population dynamics. Biological Control 25: 249–258. Polaszek, A. 2010. Species diversity and host associations of Trichogramma in Eurasia. In: Consoli, F.L, Parra, J.R.P., Zucchi, R.A. (eds.), Egg parasitoids in agroecosystems with emphasis on Trichogramma. Progress in Biological Control 9, DOI 10.1007/978-1-4020-9119-0_9, Springer Science+Business Media B.V. p. 237–265. Stouthamer, R., H. Jianguo, F.J.P.M. van Kan, G.R. Platner, and J.D. Pinto. 1999. The utility of internally transcribed spacer 2 DNA sequences of the nuclear ribosomal gene for distinguishing sibling species of Trichogramma. BioControl 43: 421–440.
