VIEW ARTICLE

Research.

Transmission of Sclerotinia minor in Peanut from Infected Seed. C. N. Akem, Department of Plant Pathology, Oklahoma State University, Stillwater 74078-9947. H. A. Melouk, USDA-ARS, Department of Plant Pathology, Oklahoma State University, Stillwater 74078-9947. Plant Dis. 74:216-219. Accepted for publication 5 October 1989. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1990. DOI: 10.1094/PD-74-0216.

Four peanut genotypes susceptible to Sclerotinia minor were grown in infested field plots at Stillwater, Oklahoma, in 1986 and 1987. Disease incidence (DI) values averaged 85–95% for all genotypes in both years. Incidence of S. minor in seed averaged 12.3% for cv. Florunner, 9.4% for TX 833841, 9.7% for cv. Okrun, and 6.8% for TX 771174. Two hundred seeds from each genotype were planted, two seeds per pot, in a steam-pasteurized mixture of soil, peat, and sand. Pots were placed close to each other on a greenhouse bench to obtain a thick canopy. Plants were watered daily and fertilized twice per month with 0.2% NH₄NO₃ from time of planting. Temperature and relative humidity were monitored by a recording hygrothermograph. Typical symptoms of Sclerotinia blight appeared on plants about 60 days after planting. Maximum DI values averaged 0.0% for TX 833841, 1.5% for Okrun, 3.5% for TX 771174, and 3.5% for Florunner.