Survey of ectotrophic root infecting fungi associated with turfgrass patch diseases in Italy

During spring and summer of 2002, turfgrasses showing patch disease symptoms were observed on golf courses and private gardens in different locations in Italy. Fungi exhibiting dark-brown ectotrophic mycelium and infection cushions were isolated from roots, stolons, and crowns of Cynodon dactylon × C. transvaalensis plants collected in southern Italy and Sardinia. One isolate produced pseudothecia on stem bases of wheat and was identified as Ophiosphaerella korrae, causal agent of spring dead spot and necrotic ring spot diseases of turfgrasses. Ectotrophic root-infecting fungi (ERIF) were also collected from diseased cool-season turfgrasses (Festuca rubra, Poa annua, P. pratensis and Agrostis stolonifera) in northern and central Italy. One isolate produced mature perithecia and was identified as Gaeumannomyces incrustans. The other isolates did not produce teleomorphs and were not identified to species. These isolates produced ectotrophic mycelium, a phialophora conidial state, in vitro mycelial growth rates of 6-13 mm d ^-1 at 28°C, curling hyphae towards the centre of colonies, and appressed mycelium on culture media; features common to Magnaporthe poae and Gaeumannomyces spp. Some of these isolates caused disease symptoms on cool-season turfgrasses maintained in growth chambers. More evidence is needed to confirm the identity the ERIF associated with turfgrasses and to prove they are primary causes of patch diseases in Italy. This is the first report of the presence of O. korrae and G. incrustans on turfgrasses in Italy.