First Report of Dollar Spot Disease, Caused by Sclerotinia Homoeocarpa, of Agrostis Stolonifera in Sweden

Dollar spot is a destructive and widespread disease affecting most turfgrass species, but until recently it has been absent from the Scandinavian countries of northern Europe. In the fall of 2014, disease symptoms consistent with dollar spot were observed on a golf course fairway in Sweden. A fungus was isolated from symptomatic turf and identified as Sclerotinia homoeocarpa on the basis of ribosomal deoxyribonucleic acid (rDNA) internal transcribed spacer (ITS) sequences, morphology, and culture characteristics. The ITS sequence was identical to isolates of S. homoeocarpa from the eastern and midwestern United States. Koch's postulates were fulfilled, confirming the S. homoeocarpa isolate as the causal agent. This is the first report of turfgrass dollar spot in Sweden and only the second report of the disease from Scandinavia. Because pesticides are rarely used in the cultivation of Scandinavian turfgrass, dollar spot disease may prove difficult to control through conventional means and potentially represents a major threat to the industry.