Influence of Neotyphodium infection on plant survival of diseased tall fescue and ryegrass

Basal necrosis resulting in death of tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) plants has been a problem when pasteurised soil has been used to investigate abiotic stresses on grasses in a greenhouse trial. The likelihood that plant death was at least partly due to fungal pathogens was indicated by the isolation of Fusarium species (F. crookwellense, F. culmorum, F. oxysporum) and Microdochium bolleyi from the necrotic lower crowns and upper roots of affected ryegrass plants (M J Christensen, unpubl. data). The development of basal necrosis in tall fescue and perennial ryegrass plants growing in pasteurised sand in a greenhouse in Hamilton, Victoria, in preparation for a trial to assess tolerance to drought stress, provided an opportunity to assess the influence of endophyte infection on the development of this condition.