Project Number: 6402-22000-047-00
Project Type: Appropriated

Start Date: Oct 01, 2005
End Date: Aug 31, 2010

Objective:
Conduct fundamental research to generate baseline data on population genetic parameters to facilitate research on mechanisms of resistance to Bt proteins at the molecular level in Lepidopteran pests of cotton. Characterize the injury potential of Lepidopterous pests (esp. Helicoverpa zea) to new transgenic cottons to develop accurate action thresholds. Determine the effects that Bt corn (Yieldgard®) has on bollworm biology including: pupal diapause, reproduction, flight potential, physiology, and the ability of progeny to survive and damage transgenic Bt cottons (Bollgard® and Bollgard II®).

Approach:
Population genetic studies for characterizing natural populations of H. virescens and H. zea are in need of a comprehensive set of genetic markers. Well defined genetic markers will also facilitate the development of linkage maps which in turn will serve as valuable tools in studying inheritance of traits. Simple sequence repeats (SSR) or microsatellites found in genomes as well as single nucleotide polymorphisms (SNP) found in gut specific genes will be used as genetic markers for H. virescens and H. zea. Genomic DNA libraries enriched for microsatellite sequences will be used to develop SSR markers. Subtraction cDNA libraries enriched for gut specific genes will be used to identify SNP markers.