Expanding Uses for Kabuto™(isofetamid) in the Turfgrass Industry.

The SDHIs (Succinate dehydrogenase inhibitors) are an older class of fungicides that disrupt fungal cell respiration by binding to the ubiquinone binding site in complex II of the mitochondria. Recently, a variety of new active ingredients in this class have been introduced into the turfgrass market for control of many of the most economically important diseases. These active ingredients typically have a niche pathogen which they effectively control, and have varying levels of efficacy against many others. Some active ingredients only demonstrate control of ascomycetes, while others control basidiomycetes effectively. Often, broad spectrum control of a variety of diseases is only achieved by tank-mixing an SDHI fungicide with a companion product. Among the recent introductions to the turfgrass disease control maket is isofetamid, a 4^th generation SDHI fungicide with structural flexibility for fitting to the binding site. Isofetamid is a suspension concentrate used for control of dollar spot disease caused by Sclerotinia homoeocarpa, and marketed under the trade name Kabuto™ by the PBI-Gordon Corporation.

Over the past two years, researchers at several universities have been evaluating Kabuto™ for control of spring dead spot (Ophiosphaerella sp.) on bermudagrass. Results across all locations have consistently demonstrated that the active ingredient isofetamid provides unparalleled control of this disease. Varying levels of disease control are achieved over a variety of application rates and spray intervals. The efficacy of Kabuto™ in controlling foliar and root infecting ascomycetes is further evidence of the specificity and utility of this class of fungicides, where continued research for new and innovative uses for the end-user are essential. Continued field research may result in additional pathogens being included on the Kabuto™ fungicide label. Incorporated in this research development is the registration of a pre-mix product which utilizes the properties of isofetamid to provide extended control of economically important turfgrass diseases.