Effect of genetic blends of dry beans (Phaseolus vulgaris) of different Plant architecture on apothecia production of Sclerotinia sclerotiorum and white mold infection

Abstract

The determinate Phaseolus vulgaris L. cvs Dark Red Kidney Charlevoix, and near-isogenic Great Northern Nebraska ≠1 were grown in blends with the indeterminate GN Nebraska ≠1 in white mold (Sclerotinia sclerotiorum) disease field nurseries. A critical difference between ‘Charlevoix’ and indeterminate ‘GN Nebraska ≠1’ is that the latter has a greater leaf area closer to the soil surface, and this is associated with increased numbers of apothecia beneath the canopy and higher disease severity. White mold infection and apothecia number/m2 beneath the canopy of the blends containing ’Charlevoix‘ were significantly reduced in comparison with the severely infected, homogeneous, indeterminate ‘GN Nebraska ≠1’. A reduction of white mold infection for the indeterminate ‘GN Nebraska ≠1’ was not observed in blends grown under severe or moderate white mold incidence, but did occur under slight incidence in blends containing 65% and 75% ‘Charlevoix’.