Introgressive Breeding for Thrips Tolerance in Upland Cotton.

Thrips are early-season insects and most growers use a pesticide as a preventive measure. Developing a thrips resistant cultivar would reduce pesticide use and lower the production costs. Pima cotton line coastland C-310 was used as a source of thrips tolerance in upland cotton. Segregating populations were screened for thrips tolerance for two summers at Clayton, North Carolina. Thrips tolerant F₄ ines have been identified and SSR markers are currently being used to characterize the thrips tolerant introgressions. Crosses are being made to further transfer this tolerance to advanced breeding lines.