636-9 Combining Multiple Disease Resistances with Medium-Maturinty in Peanut.

Tuesday, 7 October 2008
George R. Brown Convention Center, Exhibit Hall E
C. Corley Holbrook1, Albert K. Culbreath2, T. B. Brenneman2, Patricia Timper1, W. B. Dong3 and Craig K. Kvien2, (1)USDA-ARS, Tifton, GA
(2)University of Georgia Tifton Campus, Tifton, GA
(3)University of Georgia, Tifton, GA
Peanut (Arachis hypogaea) cultivars and breeding lines have been developed with multiple disease resistances. However, these genotypes typically mature 2 to 3 weeks later than standard runner-type cultivars. Growers prefer medium maturing cultivars, and the acreage for late maturing cultivars is limited. There is a need for multiple disease resistant cultivars with medium maturity. ‘Tifguard’ was developed and released as a peanut cultivar with resistance to both the peanut root-knot nematode and tomato spotted wilt virus. We have been evaluating this medium-maturity cultivar for the past two years for resistance to other diseases. Field and greenhouse studies have indicated a level of resistance to Cylindrocladium Black Rot (CBR) similar to ‘GA 02C’. Field studies have also revealed a significant level of resistance to late leaf spot (Cercosporidium personatum). The combination of moderate levels of leaf spot resistance with shorter time to maturity should allow for this cultivar to be grown with greatly reduced fungicide inputs.