Field Performance of Advanced Runner- and Virginia-Type Peanut Breeding Lines During Epidemics of TSWV

Abstract

Abstract Spotted wilt, caused by tomato spotted wilt tospovirus (TSWV), has become a major problem in peanut- (Arachis hypogaea L.) producing areas of the southern U.S. Development of cultivars with resistance to TSWV appears to be among the most promising methods for managing this disease. As part of efforts toward characterizing breeding lines with potential for release as cultivars, epidemics of spotted wilt were monitored in field plots of runner-type peanut cultivars Southern Runner and Florunner and advanced breeding lines: 79/4-6-2-1-1-Z16-b2-B (virginia-type), F 84/23-11-1-1-1-b2-B (runner-type), and F 84/28-5-5-2-2-1-b2-B (runner-type), F 84/28-5-4-2-2-b3-B (runner-type). The tests were conducted near Attapulgus, GA and Marianna, FL in 1995 and 1996. In 1996, the tests also included the runner-type cultivar AT-108. Epidemics of spotted wilt were suppressed in F 79/4-6-2-1-1-Z16-b2-B, F 84/23-11-1-1-1-b2-B, F 84/28-5-5-2-2-1-b2-B, and Southern Runner in comparison to those in Florunner. Final disease incidence and/or final disease intensity ratings in F 79/4-6-2-1-1-Z16-b2-B and F 84/23-11-1-1-1-b2-B were similar to those of Southern Runner. In 1996, final spotted wilt intensity ratings in F 84/28-5-4-2-2-b3-B and AT-108 did not differ from those of Florunner. Yields of F 79/4-6-2-1-1-Z16-b2-B and F 84/23-11-1-1-1-b2-B were superior to those of Florunner in three of the four tests. No differences were found among the genotypes in numbers of adults of tobacco thrips (Frankliniella fusca) or western flower thrips (F. occidentalis), and differences in numbers of larvae of Frankliniella spp. were few and not consistent. There was no evidence that differences in final disease incidence or disease intensity ratings were due to differential preference by thrips or to suitability for thrips reproduction. F 79/4-6-2-1-1-Z16-b2-B and F 84/23-11-1-1-1-b2-B represent potential tools for management of spotted wilt in peanut production areas of the southeastern U.S.