Inheritance and fitness costs associated with field-derived resistance to Cry3Bb1 corn in western corn rootworm (Diabrotica virgifera virgifera LeConte)

The western corn rootworm (Diabrotica virgifera virgifera LeConte) is an economically important pest of corn.  One strategy used to manage western corn rootworm is the planting of transgenic corn that produces one or more Cry toxins derived from Bacillus thuringiensis (Bt). This places selective pressure on populations to develop resistance to Bt. Refuges of non-Bt corn function to delay the development of resistance. This delay is expected to be greatest when the inheritance of resistance is recessive and fitness costs are associated with resistance.  Our research quantified the inheritance of resistance for two strains of western corn rootworm with field-derived resistance to Cry3Bb1 and tested for fitness costs associated with resistance.