Magnaporthiopsis meyeri-festucae, sp. nov., associated with a summer patch-like disease of fine fescue turfgrasses.

Summer patch is a common and destructive root disease of turfgrasses. In this study, a new Magnaporthiopsis species, M. meyeri-festucae, was identified from the roots of fine fescue (Festuca spp.) turfgrasses with summer patch-like symptoms. It is described and illustrated on the basis of phenotypic characteristics and partial sequences of rDNA 18S, internal transcribed spacer (ITS), and 28S regions, and of MCM7, RPB1, and TEF1 genes. A key for all seven described species in the genus Magnaporthiopsis is provided. Distinctions between the new species and related species are discussed. Fulfillment of Koch's postulates confirmed Magnaporthiopsis meyeri-festucae as a pathogen causing summer patch-like symptoms of fine fescue turfgrasses. This work is the basis for future studies on biogeography, host range, and impact of summer patch pathogens on a broader scale.