Glyphosate and fungicide effects on Cercospora leaf spot in four glyphosate-resistant sugar beet (Beta vulgaris) varieties

The potential for improved management of Cercospora leaf spot (CLS), caused by Cercospora beticola, using the herbicide glyphosate in glyphosate-resistant sugar beet varieties was investigated. Controlled field experiments were conducted in 2008 and 2009 to determine if glyphosate and glyphosate–fungicide combinations improved the management of CLS in four commercial varieties of glyphosate-resistant sugar beet. Variety and fungicide main effects were significant for CLS development. However, regardless of the herbicide program, glyphosate or a conventional herbicide program, CLS development was not affected. Therefore, results from of this research indicate that glyphosate and glyphosate–fungicide combinations do not significantly contribute to CLS management.

► This study provides information for improved management of Cercospora leaf spot (Cercospora beticola).
► Cercospora leaf spot development was not affected by the glyphosate or conventional herbicide program.
► Glyphosate–fungicide combinations do not significantly contribute to Cercospora leaf spot management.