Effect of Systemic Fungicides on a Bermudagrass Putting Green Infested withGaeumannomyces graminisvar.graminis

Abstract

During a 3-year period, the systemic fungicides fenarimol, myclobutanil, propiconazole, tebuconazole, thiophanate methyl, and triadimefon were evaluated for efficacy in reversing or preventing the quality decline of a hybrid bermudagrass putting green infested with Gaeumannomyces graminis var. graminis. None of the fungicides increased turfgrass quality over that of the untreated turfgrass, whether used curatively at the highest recommended rates or preventatively at a reduced rate. However, a significant decline in turfgrass quality, when compared with the untreated turfgrass, was often associated with repeated use of the DMI fungicides fenarimol, myclobutanil, propiconazole, and triadimefon but not with the use of the DMI fungicide tebuconazole or with the benzimidazole fungicide thiophanate methyl.