1230 Inheritance and dominance of Bt Cry1Ac resistance in Helicoverpa zea (Lepidoptera: Noctuidae)

Wednesday, November 19, 2008: 1:41 PM
Room A9, First Floor (Reno-Sparks Convention Center)
Jayadevi H Chandrashekhar , Department of Entomology and plant pathology, Auburn University, Auburn, AL
William J Moar , Department of Entomology and plant pathology, Auburn University, Auburn, AL
Bollworm, Helicoverpa zea was selected for resistance to Bt Cry1Ac toxin in the laboratory (AR). The genetics of resistance to Cry1Ac was characterized based on the response of single pair crosses with a laboratory susceptible homozygous strain, (SC). Resistance was found to be autosomally inherited. Based on the response of homozygous AR crossed with SC, the mean ‘h’ value was 0.81 and 0.74 at 100 and 200ppm Cry1Ac toxin, respectively. Therefore resistance is assumed to be co-dominant. Based on the test of fit using a monogenic model, 11 of the 12 single pair families fit the monogenic model when the F1 progeny were backcrossed to SC. Therefore, resistance is assumed to be governed by a single gene or a single gene with multiple loci.

doi: 10.1603/ICE.2016.38471