David's M.S. research focused on resistance of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, to transgenic corn plants producing the Bt toxin Cry3Bb1. He studied the genetic dominance and fitness costs of Bt resistance in two laboratory strains of WCR with field-derived alleles.
Keweshan, R. S., Head, G. P., and Gassmann, A. J. In Press. Effects of pyramided Bt corn and blended refuges on western corn rootworm and northern corn rootworm (Coleoptera: Chrysomelidae). Journal of Economic Entomology.
Deitloff, J., Dunbar, M. W., Ingber, D. A., Hibbard, B. E., and Gassmann, A. J. In Press. Effects of refuges on the evolution of resistance to transgenic corn by western corn rootworm. Pest Management Science. Read more about Publications
My research interests are in the areas of plant-insect and tritrophic interactions, with s 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.