Submitted to: Peanut Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/15/2016
Publication Date: 5/8/2016
Citation: Bennett, R.S., Payton, M.E., Chamberlin, K.D. 2016. Three inoculation methods for evaluating Sclerotinia blight resistance in peanut. Peanut Science. 43(1):52-58.
Interpretive Summary: Laboratory-based methods for screening peanuts for resistance to Sclerotinia blight in peanuts can be conducted at all times of the year, and thus may help peanut breeders develop resistant plants more quickly. Three inoculation methods (using main stems of intact plants, detached main stems, and detached leaflets) were compared on peanut cultivars known to represent a range of resistance to Sclerotinia blight. The intact plant and detached main stem methods identified the most resistant and susceptible peanuts, but no differences were observed among cultivars with the detached leaflet method. The three inoculation methods were also compared for efficiency using a statistical approach called the sensitivity ratio, and the intact plant assay was identified as the best of the three methods. These results help peanut breeders and pathologists by identifying the most efficient method for assaying resistance to Sclerotinia blight in the lab.
Technical Abstract: Laboratory-based assays for screening germplasm for resistance to Sclerotinia blight in peanuts can be conducted year-round, and thus may accelerate progress in breeding for resistant plants. Three previously proposed inoculation methods (using main stems of intact plants, detached main stems, or detached leaflets) were compared on six peanut genotypes known to represent range of resistance to Sclerotinia blight in the field or laboratory. The intact plant and detached main stem assays identified the most resistant and susceptible genotypes, but different results were obtained from each assay with Red River Runner, a cultivar with intermediate resistance to Sclerotinia blight. No differences among genotypes were observed with the detached leaflet assay. The sensitivity ratio was used to compare the three inoculation methods and identified the intact plant assay as the method with the smallest error variance. These results help identify the most efficient method for assaying physiological resistance to Sclerotinia blight in peanut.