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ADVERSE IMPACTS OF TRANSGENIC CROPS/FOODS :A COMPILATION OF SCIENTIFIC REFERENCES WITH ABSTRACTSresistance to a Bt toxin by the western corn rootworm and by any species ofColeoptera. Insufficient planting of refuges and non-recessive inheritance ofresistance may have contributed to resistance. These results suggest thatimprovements in resistance management and a more integrated approach tothe use of Bt crops may be necessary.5. Jennifer H. Zhao, Peter Ho, Hossein Azadi (2011) : Benefits of Bt cottoncounterbalanced by secondary pests? Perceptions of ecological changein China. Environmental Monitoring and Assessment. Volume 173, Issue1-4, pp 985-994In the past, scientific research has predicted a decrease in the effectiveness of Btcotton due to the rise of secondary and other sucking pests. It is suspected thatonce the primary pest is brought under control, secondary pests have a chance toemerge due to the lower pesticide applications in Bt cotton cultivars. Studies onthis phenomenon are scarce. This article furnishes empirical evidence thatfarmers in China perceive a substantial increase in secondary pests after theintroduction of Bt cotton. The research is based on a survey of 1,000 randomlyselected farm households in five provinces in China. We found that the reductionin pesticide use in Bt cotton cultivars is significantly lower than that reported inresearch elsewhere. This is consistent with the hypothesis suggested by recentstudies that more pesticide sprayings are needed over time to control emergingsecondary pests, such as aphids, spider mites, and lygus bugs. Apart fromfarmers’ perceptions of secondary pests, we also assessed their basicknowledge of Bt cotton and their perceptions of Bt cotton in terms of its strengthsand shortcomings (e.g., effectiveness, productivity, price, and pesticide use) incomparison with non-transgenic cotton.http://dx.doi.org/10.1007/s10661-012-2699-56. Dhurua S and Gujar GT (2011) : Field-evolved resistance to Bt toxin Cry1Acin the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera:Gelechiidae) from India. Pest Management Science. Vol. 67 (8) : 898-903.The pink bollworm is one of the most destructive pests of cotton. Transgeniccotton producing Bt toxin Cry1Ac or a combination of Cry1Ac and Cry2Ab2 hasbeen used effectively against this pest. However, some other insects have evolvedresistance to Bt toxins in the field. During the 2007–2008 and 2008–2009 seasons,pink bollworm populations in India were surveyed to evaluate their responses toCry1Ac and seed powder containing Cry1Ac and Cry2Ab2. The results provideevidence that resistance to Cry1Ac had evolved by 2008 in a population sampledfrom non-Bt cotton in the Amreli district of Gujarat in western India. The medianlethal concentration of Cry1Ac for five-day-old larvae (LC 50) was significantly higherfor insects derived in 2008 from Amreli than for any of the other field populationstested from four locations in India. For Cry1Ac, the mean LC 50for the strain derivedfrom Amreli in 2008 was 44 times higher than for the most susceptible population.However, for seed powder of Bollgard II containing primarily Cry2Ab2, the 2008(126)