Wednesday, November 7, 2007
258-1

Development of a Peanut Cultivar with Resistance to the Peanut Root-knot Nematode and Tomato Spotted Wilt Virus.

C. Corley Holbrook1, Patricia Timper1, Craig K. Kvien2, and Albert K. Culbreath2. (1) USDA-ARS, USDA-ARS, PO Box 748, Tifton, GA 31793, (2) University of Georgia Tifton Campus, P.O. Box 748, Tifton, GA 31793

The peanut root-knot nematode and tomato spotted wilt virus are pathogens of peanut that result in large yield losses in the southeastern United States. Peanut cultivars are available that have resistance to either the peanut root-knot nematode or tomato spotted wilt virus, however, no cultivars are available that have resistance to both pathogens. Our objective was to combine resistance to both pathogens in a single genotypes with high yield and grade. Breeding populations were developed by hybridizing the TSWV resistance cultivar, ‘C-99R' with the nematode resistant cultivar, ‘COAN'. Selection for nematode resistance was conducted using standard greenhouse screening techniques. Selection for TSWV resistance was conducted in the field with natural virus infection. Several breeding lines were selected that had high resistance to both pathogens. The breeding line C724-19-15 exhibited higher resistance to TSWV and higher yield than standard check cultivars when grown in fields with little or no nematode pressure. Because of its high level of resistance to both TSWV and M. arenaria, this breeding line had almost twice the yield of standard cultivars when grown in two locations with high pressure from both pathogens.