Field assessment of the effects of transgenic rice expressing a fused gene of cry1Ab and cry1Ac from Bacillus thuringiensis Berliner on nontarget planthopper and leaf hopper populations

Abstract

In 2003 and 2004, field studies were conducted at three sites in Zhejiang Province in China to assess the impacts of Bacillus thuringiensis (Bt) Berliner rice expressing a fused gene of cry1Ab and cry1Ac on nontarget planthoppers and leafhoppers. Populations in Bt plots were sampled with yellow sticky card traps, Malaise traps, and a vacuum-suction machine, and compared with samples from non-Bt control (IR72) plots. The results from yellow sticky card trap samplings indicated no significant differences between Bt and non-Bt plots in the species composition or densities of each species of planthopper and leafhopper. Three species of planthoppers, Sogatella furcifera (Horvath), Nilaparvata lugens (Stål), and Laodelphax striatellus (Fallén), were collected at all sites, and three species of leafhoppers, Nephotettix cincticeps (Uhler), Thaia subrufa (Motschulsky), and Recilia dorsalis (Motschulsky), were collected at Hangzhou. Another species of leafhopper, N. virescens (Distant), was collected at Anji and Jiande instead of T. subrufa. The results from the Malaise trap and vacuum-suction samples revealed no significant differences between Bt and non-Bt plots in species structure of planthoppers and leafhoppers or in population changes of the predominant planthopper species, S. furcifera, the predominant leafhopper species, N. cincticeps, or N. virescens throughout most sampling dates. Densities of planthoppers and leafhoppers were significantly affected by year and site but not by Bt rice. In general, our results suggest that the Bt rice line tested did not adversely affect nontarget planthopper and leafhopper populations and will not lead to higher populations or damage by planthoppers and leafhoppers.