Morphological and Molecular Characterization of Sclerotinia sclerotiorum on Sugar Beet in Montana, U.S.A

In this contribution, we report on a survey of leaf blight on sugar beet in the Sidney factory district of Montana caused by the soilborne fungus Sclerotinia sclerotiorum. In addition to morphological and pathological characterization of the pathogen on sugar beet, we confirmed the molecular identity of the fungus by DNA sequence analysis of the ribosomal internal transcribed spacer region. Our findings are significant because the sugar beet production in south-central and eastern Montana contributes more than $100 million in economic activities. The incidence of this emerging disease will require changes in conventional disease management.