Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: June 13, 2006
Publication Date: July 11, 2006
Citation: Melouk, H.A., Grichar, W.J., Pittman, R.N. 2006. Reaction of peanut genotypes to Southern blight in small field plots [abstract]. In: 2006 Proceedings of the American Peanut Research and Education Society, July 11-14, 2006, Savannah, Georgia. p. 23-24. Available: http://www.apres.okstate.edu/Vol%2038%20Proc.pdf. Technical Abstract: Southern blight of peanut (Arachis hypogaea L.) is a serious disease caused by the fungus Sclerotium rolfsii. The disease negatively impacts peanut production in all growing areas of the United States. Eleven peanut genotypes (PI 501983, 501996, 502046, 502071, 502093, 502154, Grif 13826, Okrun, Southwest Runner, Valencia A, and Valencia B) were planted at Yoakum, TX, in 2004 and 2005. Sclerotial density of S. rolfsii was 2-3 viable sclerotia per 225 g of soil (Tremona loamy fine sand) for both years. The study in both years had four replications in a randomized complete block design, with each plot consisting of two 5-m rows, with row spacing of 0.91 m. Disease incidence (%) of southern blight was recorded in both years at harvest (about 150 days post planting). In 2004 and 2005, PI 502093 (a runner type peanut of Peruvian origin) had 2 and 3% disease incidence which was significantly (P=0.05) different from Southwest Runner which had disease incidence of 15 and 11%, respectively. Furthermore, the average pod yield and grade (% sound mature kernels plus sound splits) of the PI 502093 in both years was not significantly (P=0.05) different from Southwest Runner. The data confirm that the peanut PI 502093 has useful resistance to Southern blight which makes attractive as a parental line for breeding programs because of its comparable agronomic quality to Southwest Runner.