title: Mortality of western corn rootworm larvae on MIR604 transgenic maize roots: field survivorship has no significant impact on survivorship of F1 progeny on MIR604.
abstract: Mortality of western corn rootworm, Diabrotica virgifera virgifera LeConte, larvae due to MIR604 transgenic corn, Zea mays L., expressing the modified Cry3A (mCry3A) protein relative to survivorship on corn with the same genetic background without the gene (isoline corn) was evaluated at three Missouri sites in both 2005 and 2006. We made these comparisons by using wild-type western corn rootworm at three different egg densities (6,000, 3,000, and 1,500 eggs per m) so that the role of density-dependent mortality would be known. The mortality due to the mCry3A protein was 94.88% when averaged across all environments and both years. Fifty percent emergence of beetles was delayed approximately 5.5 d. Beetles were kept alive and their progeny evaluated on MIR604 and isoline corn in the greenhouse to determine whether survivorship on MIR604 in the field for one generation increased survivorship on MIR604 in the greenhouse in the subsequent generation. There was no significant difference in survivorship on MIR604 in greenhouse assays between larvae whose parents survived isoline and larvae whose parents survived MIR604 in the field the previous generation, indicating that many susceptible beetles survived MIR604 in the field the previous season along with any potentially resistant beetles. The data are discussed in terms of rootworm insect resistance management.
authors.affiliation: USDA-ARS, Plant Genetics Research Unit, 205 Curtis Hall, University of Missouri, Columbia, MO 65211, USA. bruce.hibbard@ars.usda.gov
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Hibbard
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Clark
authors.forename: Mark R
authors.initials: MR
authors.lastname: Ellersieck
authors.forename: Lisa N
authors.initials: LN
authors.lastname: Meihls
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: El Khishen
authors.forename: Von
authors.initials: V
authors.lastname: Kaster
authors.forename: Henry-York
authors.initials: HY
authors.lastname: Steiner
authors.forename: Ryan
authors.initials: R
authors.lastname: Kurtz
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001517:Coleoptera; D004731:Endotoxins; D005260:Female; D006460:Hemolysin Proteins; D007306:Insecticides; D007814:Larva; D018517:Plant Roots / Q000469:parasitology; D030821:Plants, Genetically Modified / Q000469:parasitology*; D003313:Zea mays / Q000235:genetics / Q000469:parasitology*
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis