|PUPPALA, NAVEEN - New Mexico State University|
Submitted to: Peanut Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/29/2017
Publication Date: 6/1/2018
Citation: Chamberlin, K.D., Puppala, N. 2018. Genotyping of the Valencia peanut core collection with a molecular marker associated with Sclerotinia blight resistance. Peanut Science. 45(1):12-18.
Interpretive Summary: Sclerotinia blight on peanut is a major profit-limiting disease in many U.S. peanut production regions, including New Mexico where Valencia peanuts are grown organically. Organic production restrictions prohibit the use of fungicides for disease control, thus resistant cultivars are needed for sustainable production in that region. In this study, the Valencia peanut core germplasm collection was screened for possible new sources of Sclerotinia blight resistance using a molecular marker associated with resistance to that disease in peanut. Results of this study identified 30 new potential sources of Sclerotinia blight resistance that can be used by breeding programs focusing on the Valencia market-type.
Technical Abstract: Cultivated peanut, the second most economically important legume crop throughout the United States and the third most important oilseed in the world, is consistently threatened by various diseases and pests. Sclerotinia blight, (causal agents Sclerotinia sclerotiorum (S. sclerotiorum) and Sclerotinia minor Jagger (S. minor)) is a major threat to peanut production in the Southwestern U.S., Virginia, and North Carolina and can reduce yield by up to 50% in severely infested fields. S. sclerotiorum has now been reported in areas of New Mexico and Texas where all U.S. grown Valencia peanuts are grown, commonly in organic cropping environments. Host plant resistance provides the most effective solution to managing Sclerotinia blight, especially in organic systems where pesticide use is not an option for disease control. To date, no Valencia cultivars with Sclerotinia blight resistance have been released. In this study, the Valencia peanut core germplasm collection was genotyped with a marker associated with Sclerotinia blight resistance in order to identify potential candidates for breeding Valencia cultivars resistant to the disease. The results from this genotyping identified 30 accessions from the Valencia peanut core collection that have profiles consistent with other genotypes that exhibit less that 5% incidence of Sclerotinia blight under heavy disease pressure. The identified accessions should serve as potential sources of Sclerotinia blight resistance in Valencia peanut breeding programs.