Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Iowa State University

Entomology

Resistance

Articles 1 - 2 of 2

Full-Text Articles in Life Sciences

High-Level Resistance To Bacillus Thuringiensis Toxin Cry1ac And Cadherin Genotype In Pink Bollworm, Aaron J. Gassmann, Robert W. Biggs, Jeffrey A. Fabrick, Bruce E. Tabashnick, Timothy J. Dennehy, Yves Carriere, Shai Morin Dec 2006

High-Level Resistance To Bacillus Thuringiensis Toxin Cry1ac And Cadherin Genotype In Pink Bollworm, Aaron J. Gassmann, Robert W. Biggs, Jeffrey A. Fabrick, Bruce E. Tabashnick, Timothy J. Dennehy, Yves Carriere, Shai Morin

Aaron J. Gassmann

Resistance to transgenic cotton, Gossypium hirsutum L., producing Bacillus thuringiensis (Bt) toxin Cry1Ac is linked with three recessive alleles of a cadherin gene in laboratory-selected strains of pink bollworm, Pectinophora gossypiella (Saunders), a major cotton pest. Here, we analyzed a strain (MOV97-R) with a high frequency of cadherin resistance alleles, a high frequency of resistance to 10 μg of Cry1Ac per milliliter of diet, and an intermediate frequency of resistance to 1,000 μg of Cry1Ac per ml of diet. We selected two strains for increased resistance by exposing larvae from MOV97-R to diet with 1,000 μg of Cry1Ac per ml …


Corn Phenology Influences Diabrotica Virgifera Virgifera Emigration And Visitation To Soybean In, Matthew E. O'Neal, D. A. Landis, J. R. Miller Feb 2004

Corn Phenology Influences Diabrotica Virgifera Virgifera Emigration And Visitation To Soybean In, Matthew E. O'Neal, D. A. Landis, J. R. Miller

Matthew E. O'Neal

We used two types of laboratory apparatus to test whether rotation-resistant and wild-type Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) responded differently to corn phenology. Beetles from Nebraska where injury to rotated corn has not been reported were defined as wild type, and beetles from Illinois where injury to rotated corn is common represented “rotation-resistant“ populations. A two-chamber emigration arena assayed propensity of both populations to leave corn during and after anthesis. A side-arm olfactometer tested whether the relative attraction of beetles to soybean versus corn was influenced by corn phenology. Beetle origin did not influence departure from corn of varying …