Entomology Commons^™

Synergism Between Entomopathogenic Nematodes And Bacillus Thuringiensis Crops: Integrating Biological Control And Resistance Management, Aaron J. Gassmann, S. Patricia Stock, Mark S. Sisterson, Yves Carriere, Bruce E. Tabashnik

Aaron J. Gassmann

The past decade has witnessed a continual increase in the use of crops genetically modified to produce insecticidal toxins from the bacterium Bacillus thuringiensis (Bt). This presents the challenge of designing agricultural systems to manage pests and the evolution of resistance to Bt. We tested whether entomopathogenic nematodes might act synergistically with Bt crops by killing pests in non-Bt refuges and by increasing the fitness costs of resistance to Bt. We also tested whether insect mortality and fitness costs were affected by the cotton phytochemical gossypol. The entomopathogenic nematode Steinernema riobrave increased the fitness cost of Bt resistance, indicating that …