Location: Plant Genetics Research
2013 Annual Report
The current project is related to parent project sub-objective 1.B “Evaluate our mCry3A-resistant colony for the heredity of this trait, whether the trait is maintained when selection is removed, and whether there are fitness costs associated with the trait” and sub-objective 1.C. “Evaluate cross resistance in rootworm colonies selected for resistance to one rootworm product on other single and stacked trait products.” It also contributes to Component 2A of the National Program 304 Action Plan by developing increased knowledge of the biology, ecology, behavior, and genetics of pests, and plant traits conferring pest resistance.
Transgenic corn with resistance to corn rootworm larval feeding has been an effective option for rootworm management since it became available in 2003. Unfortunately, resistance has developed in the field to at least the original Bt product. A series of experiments were conducted by ARS scientists in Columbia, MO aimed at understanding rootworm feeding behavior on Bt corn as a potential mechanism of resistance. To this point, available evidence does not point toward feeding behavior as playing a major role in the development of resistance of the western corn rootworm to Bt corn. Data are important to seed companies and modelers attempting to optimize resistance management plans for transgenic corn required by the Environmental Protection Agency for commercialization.