Field monitoring of Helicoverpa armigera (Lepidoptera: Noctuidae) Cry1Ac insecticidal protein resistance in China (2005-2017).

Abstract

Bt cotton expressing Cry1Ac can efficiently control Helicoverpa armigera, but field-evolved Bt resistance reduces its efficacy. Susceptibility of H. armigera field populations to Cry1Ac protein has been monitored since Bt cotton was commercialized in 1997 in China. Here we report the results of our continued monitoring from 2005 to 2017 to provide important guidelines for sustainably growing cotton.