Abstract: Prey-mediated effects of genetically manipulated (GM) plants on polyphagous natural enemies were studied. Transgenic cotton cv. SGK321 (with inserted genes of Cry1Ac and CpTI) was used as the GM, the cotton aphid Aphis gossypii as the model pest, and the wolf spider Alopecosa pulverulenta (Clerck) as the generalist natural enemy. Aphids reared on GM vs. non-GM cotton were both poor quality food for A. pulverulenta spiderlings, in terms of growth and mortality. But the spiderlings showed higher survival and developed better when they were fed with aphids and fruit flies alternatively. When fed with aphids only, there were no differences in impact whether prey aphids were from GM or non-GM cotton, both in the limited feeding and unlimited feeding regimes. In the unlimited feeding experiment, the spiderlings showed higher survival when they were fed with aphids from GM cotton and fruit flies alternatively, compared with those fed with aphids from non-GM cotton and fruit flies alternatively, but body mass of the spiderlings did not differ between these two treatments. In the limited and mixed feeding experiment, there were no differences in impact whether prey aphids were from GM or non-GM cotton. The results indicate that transgenic cotton cv. SGK321 has no significant adverse effects on the survival and development of the wolf spider through non-target prey cotton aphid.

Key words: transgenic cotton, environmental impact assessment, food quality, mortality, growth, natural enemy