Management of Take-All Patch of Creeping Bentgrass with Nitrogen, Sulfur, and Phenyl Mercury Acetate. Peter H. Dernoeden, Associate Professor, Department of Agronomy, University of Maryland, College Park 20742. Plant Dis. 71:226-229. Accepted for publication 9 October 1986. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0226.

Take-all patch disease, incited by Gaeumannomyces graminis var. avenae, is a destructive disease of bentgrass (Agrostis spp.) turf. Ammonium chloride alone and phenyl mercury acetate plus ammonium sulfate effectively controlled the disease in both years of a field study. Ammonium sulfate and urea reduced disease severity to an acceptable level only in the second year. Granular sulfur was ineffective in controlling take-all patch. No correlation was found between disease injury and thatch or soil pH. Failure to find a correlation between disease and pH was possibly due to the highly buffered nature of thatch and to the use of basic (pH 8.2) irrigation water. Data indicate that treatment effects on thatch and soil pH (pH 6.1–6.8) had no important impact on the disease control observed. Treatments that effectively reduced disease increased thatch biomass, which was attributed to stimulation of plant growth accorded by nitrogen.

Keyword(s): Agrostis palustris, Ophiobolus patch.