Measuring fitness costs and inheritance for resistance to Bt corn by western corn rootworm

Western corn rootworm, Diabrotica virgifera virgifera LeConte, is an important pest of corn. Management often includes planting transgenic corn that produces Bt toxin, which places selective pressure on populations to develop Bt resistance. Refuges delay the development of this resistance, but the effectiveness of refuges can be affected by both the inheritance of resistance traits and the presence of fitness costs associated with resistance, with greater delays in resistance achieved when fitness costs are present and resistance is recessive.  Our research will quantify the inheritance of resistance and the associated fitness costs for strains of western corn rootworm with field-derived resistance to Bt corn.