Submitted to: American Phytopathology Society
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 2003
Publication Date: November 15, 2003
Citation: Melouk, H.A., Besler, B.A., Grichar, W.J., Pittman, R.N. 2003. Reaction of peanut genotypes to southern blight under field conditions [abstract]. Phytopathology. 93:S60. Technical Abstract: Six peanut (Arachis hypogaea L.) genotypes of a Bolivian origin (PI 339967, 475971, 475972, 497412, 540866, and Bayo Grande) and two runner cultivars (Okrun and Tamrun 96) were evaluated in replicated field plots at Yoakum, TX, for their reaction to a moderate southern blight pressure in 2000 and 2001. Sclerotial density of Sclerotium rolfsii was 2-3 viable sclerotia/225 g soil (Tremona loamy fine sand). There was a treatment by year interaction, and therefore, data from the 2000 and 2001 experiments were subjected separately to analysis of variance. In 2000, all genotypes had significantly (P = 0.05) lower southern blight disease incidence than Okrun, with 13.0 loci/plot. In 2001, PI 339967, 475972, 540866, Bayo Grande, and Tamrun 96 had significantly (P = 0.05) lower disease incidence than Okrun, with 13.8 loci/plot. These data confirms that at least four genotypes have useful resistance to S. rolfsii.