My research interests are in the areas of plant-insect and tritrophic interactions, with a focus on insects that attack corn Zea mays L. General themes include applications of ecological and evolutionary principles to improve integrated pest management and insect resistance management. Most of my work addresses questions concerning adaptation by pests to genetically modified crops that produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt), and tritrophic interactions among insects, plants and entomopathogens. Recently, I have studied topics including fitness costs and inheritance of traits conferring resistance to Bt crops, field-evolved resistance to Bt corn by western corn rootworm Diabrotica virgifera virgifera LeConte, integrated pest management for western corn rootworm, and effects of agricultural practices and Bt corn on interactions between western corn rootworm and entomopathogens.