Host Plants Dependent Prey Suitability of Predatory Lady Beetles

Abstract

 

Host plants play an important role in the suitability of preys for development of predatory insects. The suitability of Aphis gossypii(Glover) (Hemiptera: Aphididae) from different host plant species, Solanum xanthocarpum Schrad. and Wendl. (Solanaceae)and Chromolaena odorata (L.) (Asteraceae) as food sources for two lady beetle species, Menochilus sexmaculatus Fab. and Micraspis discolor (Fabricius) (Coleoptera: Coccinellidae) was evaluated by examining the effect of prey consumption on the performance of lady beetle larvae. Results demonstrated that A. gossypii from S. xanthocarpum was more suitably for larval growth than A. gossypiifrom C. odorata, with faster development time and higher larval survival of both lady beetle species. Consistent with the results of larval performance, larvae of M. sexmaculatus showed feeding preference on A. gossypii from S. xanthocarpum over A. gossypiifrom C. odorata. For M. discolor, however, longer development time of larvae when reared on A. gossypii from C. odorata result higher consumption on A. gossypii from C. odorata. Regardless of lady beetle species and aphid, 4th larval instar was the most voracious. Menochilus sexmaculatus was likely resistant to toxic of host plant of aphid, C. odorata, while M. discolor was susceptible to noxious allelochemicals of C. odorata distinctly. The different of essential prey and alternative prey of both lady beetle species was discussed in this study.