Crop rotation mitigates impacts of corn rootworm resistance to transgenic Bt corn

Abstract

Significance The western corn rootworm, a major insect pest in the Midwestern United States, has evolved resistance to genetically engineered corn that produces insecticidal proteins derived from the bacterium Bacillus thuringiensis (Bt). To evaluate tactics for reducing the damage caused by resistant rootworms, we analyzed field data for 2011 to 2016 from Illinois, Iowa, and Minnesota. The frequency of corn fields with severe rootworm damage was reduced by rotating corn with other crops and by not planting the same type of Bt corn year after year in the same field. These results support the EPA’s recommendations to decrease the negative impacts of rootworm resistance to Bt corn by rotating corn with other crops and diversifying the type of Bt corn planted.