title: Mating Success, Longevity, and Fertility of Diabrotica virgifera virgifera LeConte (Chrysomelidae: Coleoptera) in Relation to Body Size and Cry3Bb1-Resistant and Cry3Bb1-Susceptible Genotypes.
abstract: Insect resistance to population control methodologies is a widespread problem. The development of effective resistance management programs is often dependent on detailed knowledge regarding the biology of individual species and changes in that biology associated with resistance evolution. This study examined the reproductive behavior and biology of western corn rootworm beetles of known body size from lines resistant and susceptible to the Cry3Bb1 protein toxin expressed in transgenic Bacillus thuringiensis maize. In crosses between, and within, the resistant and susceptible genotypes, no differences occurred in mating frequency, copulation duration, courtship duration, or fertility; however, females mated with resistant males showed reduced longevity. Body size did not vary with genotype. Larger males and females were not more likely to mate than smaller males and females, but larger females laid more eggs. Moderately strong, positive correlation occurred between the body sizes of successfully mated males and females; however, weak correlation also existed for pairs that did not mate. Our study provided only limited evidence for fitness costs associated with the Cry3Bb1-resistant genotype that might reduce the persistence in populations of the resistant genotype but provided additional evidence for size-based, assortative mating, which could favor the persistence of resistant genotypes affecting body size.
authors.affiliation: North Central Agricultural Research Laboratory (NCARL), USDA-ARS, 2923 Medary Ave., Brookings, SD 57006, USA. wade.french@ars.usda.gov.
authors.forename: Bryan Wade
authors.initials: BW
authors.lastname: French
authors.affiliation: NCARL, USDA-ARS, 13786 Thomas Place, Keystone, SD 57751, USA. hammackl@mt-rushmore.net.
authors.forename: Leslie
authors.initials: L
authors.lastname: Hammack
authors.affiliation: Department of Entomology and Wildlife Ecology, University of Delaware, Newark, DE 19716, USA. dtallamy@udel.edu.
authors.forename: Douglas W
authors.initials: DW
authors.lastname: Tallamy
keywords: copulation duration; courtship duration; leaf beetle; life history traits; mating frequency; transgenic maize; western corn rootworm