Eliseu Pereira, eliseu@unlserve.unl.edu1, Meibao Zhuang, mzhuang@dow.com2, Nick Storer, nstorer@dow.com2, Herbert Siqueira, siqueira@unlserve.unl.edu1, and Blair D. Siegfried, BSIEGFRIED1@unl.edu1. (1) University of Nebraska, Department of Entomology, 202 Plant Industry Bldg, Lincoln, NE, (2) Dow AgroSciences, 9330 Zionsville Rd, Indianapolis, IN
One important step in designing sound insect resistance management to Bt transgenic maize is to obtain laboratory colonies selected for resistance to a particular toxin. A colony of O. nubilalis was established from field collections within the US Central Corn Belt in 1996 and chronically exposed to Cry1F. The selected colony developed high levels of resistance to Cry1F but a narrow spectrum of cross resistance. Cry1F resistance in this colony is recessively inherited and controlled by a single locus or a set of tightly linked loci. Cry1F binding to brush border membrane vesicles (BBMV) of susceptible and resistant larvae was compared using surface plasmon resonance and ligand-toxin immunoblot analysis to test the hypothesis that resistance involves reduction of toxin binding to BBMV. We also examined proteolytic degradation of Cry1F as a candidate mechanism of resistance.
Species 1: Lepidoptera Crambidae
Ostrinia nubilalis (European corn borer)
Keywords: Transgenic maize, Resistance management
