Host Traits Influencing Severity of White Mold of Potatoes in a Rainfed Environment

Differences among cultivars of Solanum tuberosum L. in susceptibility to Sclerotinia sclerotiorum (Lib.) de Bary have been noted through observation and research. Traits hypothesized as having a potential effect upon susceptibility included, flower propensity, time to 50 % flowering, flowering duration, canopy density, oxalic acid sensitivity, and maturity. Field plots were planted using seven cultivars in which these variables were quantified and analyzed. Identification of those factors providing the greatest amount of information towards disease severity were identified using multiple linear regression, and parameter selection using Akaike’s Information Criterion. The factors of maturity (R²?=?0.77), time to 50 % flower (R²?=?0.64), and oxalic acid sensitivity (R²?=?0.57) were identified as providing the greatest predictive indices of white mold severity in potatoes.