Disease Note

Association of Tomato Spotted Wilt Virus with Foliar Chlorosis of Peanut in Georgia. A. K. Culbreath, University of Georgia, Coastal Plain Experiment Station, Tifton 31793. A. S. Csinos, T. B. Brenneman, J. W. Demski, and J. W. Todd. University of Georgia, Coastal Plain Experiment Station, Tifton 31793; Georgia Experiment Station, Griffin 30223; and Coastal Plain Experiment Station, Tifton, GA 31793. Plant Dis. 75:863. Accepted for publication 2 April 1991. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-0863C.

Peanut (Arachis hypogaea L.) plants with general foliar chlorosis and root necrosis were observed in Georgia in peanut fields having high incidence of tomato spotted wilt virus (TSWV) in September and October 1989 and 1990. Twenty to 30 plants with these symptoms, but without other symptoms indicative of TSWV or other diseases, were collected from each of four fields in Tift County in October 1989 and from one field in October 1990. Adjacent asymptomatic plants also were collected in 1990. Samples of leaf and root tissue were assayed for the presence of the common or "L" strain of TSWV using a commercial ELISA (Agdia, Inc., Elkhart, IN). Root tissue also was plated on potato-dextrose agar for isolation of fungi. TSWV was detected in 92, 70, 92, and 88% of root samples and 0, 0, 32, and 8% of leaf samples from the four locations in 1989, and Fusarium sp. was isolated from 60, 56, 64, and 96% of the root samples. In 1990, TSWV was detected in 90 and 23% of root and foliar samples, respectively, from chlorotic plants vs. 23 and 0%, respectively, from asymptomatic plants. Fusarium sp. was isolated from 53% of chlorotic plants and 56% of healthy plants. The roles of TSWV and Fusarium sp. in development of the chlorosis and root necrosis have not been elucidated. However, TSWV was detected more often in roots of chlorotic plants than in roots of asymptomatic plants, whereas Fusarium sp. was equally abundant in both.