Study on the insect community of single transgenic Bt cotton field

Insect community of single transgenic Bt cotton field were studied in three experimental plots of cotton,where the transgenic Bt cotton R93 4 was planted and integrated pest management was carried out (IPM),pests were controlled only by their natural enemies (NEC),and the routine cotton CCRI No.12 was with no insecticide application throughout whole growing seasons (CK).The result showed that the number of species,evenness index and dominant concentration index of the insect community and the sub community in transgenic Bt cotton fields were all higher than that in routine cotton field,and that the total number,and the abundance of the pests and diversity index were all lower than that in routine cotton fields.Cotton Bollworm was not the dominant pest of transgenic Bt cotton field,but the aphids and red spider mite become the dominant pests.The insect community and pest sub community in IPM were more stable as compared with those in CK.