Evaluating Tripsacum-introgressed maize germplasm after infestation with western corn rootworms (Coleoptera: Chrysomelidae)

Corn rootworm larvae consume maize root tissues, thus negatively impacting plant physiology and function (Riedell 1990; Hou et al. 1997; Riedell and Reese 1999), and impeding harvesting due to stalk lodging (Sutter et al. 1990). Ultimately, larval rootworm feeding reduces yield (Sutter et al. 1990; Spike and Tollefson 1991), and can cause significant economic losses (Metcalf 1986). Pesticides, crop rotation, and transgenic hybrids that express insecticidal proteins derived from Bacillus thuringiensis Berliner (Bt) are commonly used to manage larval rootworm populations (Wilson et al. 2005), although there are drawbacks and limitations to current control methods. Broad-spectrum pesticides applied as seed treatments, directly to the soil, and for adult rootworm control can negatively affect human health and the environment, and corn rootworms have evolved resistance to some of these insecticides (Ball and Weekman 1962; Meinke et al. 1998). In some areas, rootworms have adapted to crop rotation by laying eggs in alternate crops such as soybean, Glycine max L. (Levine et al. 2002;