Foliar-applied fungicide for white mold control may reduce common bean seed-borne Sclerotinia sclerotiorum

We hypothesized that foliar-applied fungicide for white mold (WM) management, especially when associated with partially resistant genotypes to WM, could reduce the incidence of common bean seed-borne Sclerotinia sclerotiorum. Seeds from three irrigated field trials with low/moderate, moderate or high WM pressure were evaluated using the Neon test. In these trials, genotype (partially resistant, intermediate resistant, or susceptible to WM) was combined with fluazinam (0, 1, 2, or 3 applications). The fungicide-genotype interaction was nonsignificant for the seed infection frequency of S. sclerotiorum, partially refuting our hypothesis. However, compared to no fungicide application, two applications resulted in a 6.5-fold reduction in the seed infection frequency, indicating that fungicide applications may contribute to reducing seed infection by this fungus.