Comparative studies on the effects of Bt-transgenic and nontransgenic cotton on arthropod diversity, seedcotton yield and bollworms control.

摘要: The effectiveness of commercial Bt-cotton in pest management, influence on arthropod diversity, natural enemies, and toxin flow the insect fauna under field conditions were studied keeping view need to assess bioefficacy biosafety Bt-transgenic cotton. There no significant differences oviposition by Helicoverpa armigera non-transgenic cottons (9.2 versus 9.6 eggs plants-100), while numbers H. larvae significantly more than (10.4 4.0 plants-100) had number mature opened bolls (9.6 4.4 plant-1), lower bollworm damage (12.8 40.2% damaged), higher seedcotton yield (667.7 231.7 kg ha-1). Population cotton leafhopper, Amrasca biguttula was (582.2 732.2 leafhoppers that whitefly, Bemisia tabaci (65.2 45.6 whiteflies abundance enemies crop pests – chrysopids 8.4 ladybird beetles (16.0 10.8 ladybirds spiders (128.4 142.8 plants-100). egg (19.8 20.9%), larval (7.4 9.6%), larval-pupal (1.3 2.9%) parasitism farmer’s fields. far eggs, which might be because early mortality prior parasitoid development host larvae. Although, Cry1Ac Bt detected Cheilomenes sexmaculatus, chrysopids, A. bigutulla bigutulla, Thrips tabaci, Myllocerus sp., Oxycarenus laetus, Dysdercus koenigii, spiders, bugs, grasshoppers, observed their cottons, suggesting there adverse effects diversity conditions.