A Study On Influences To Insect Community Of Transgenic Cotton

Cotton is one of the most important economic plant and bollworm is the most serious pest on cotton. Since the commotional control of bollworm was mainly dependent on chemical reagents, bollworm was forced to gain resistance against chemical. Although transgenic Bt cotton resistance to bollworm efficiency, the consistent expression of resistance gives high pressure on bollworm, which force bollworm to overcome Bt cotton. Furthermore, insect community in the cotton field will change accordingly.The objective of this research was to analyze the affect of transgenic cotton on insect community in cotton field, to investigate the manipulation of transgenic cotton on bollworm, non target pest and natural enemies.This research was investigated on three treatment spots, traditional cotton, control natural enemies control (NEC) in transgenic Bt cotton and Integrated pest management (IPM). The number of bollworm egg decreased optionally in NEC and IPM compared to control and transgenic cotton confer efficient resistance to bollworm. Moreover, transgenic cotton showed efficient resistance to cotton aphid, cotton spider mite and Thrips tabaci.Diversity varies among IPM, NEC and control, and the population structure of insect community consisted of 7 natural enemies subcommunity and 13 pest subcommunity for NEC, 7 natural enemies subcommunity and 14 pest subcommunity for IPM, and 7 natural enemies sub community and 16 pest subcommunity for control.The total number of insect varied among the three cotton field, 44870 for control, whereas 27204 for NEC and 22002 for IPM.Dominant pests in control field were thrips tabaci, Aphids, Spider mite and bollworm , whereas in transgenic Bt cotton field, bollworm not the main pest anymore, and thrips tabaci, and spidor mite and aphid took up dominance. From the investigation of insect community in trays cotton field, an integrated pest management was suggested to kill dominant pests and protect natural enemies simulation...