Mycosphaerella species occurring on Eucalyptus globulus and Eucalyptus nitens plantations of Tasmania, Australia

The genus Mycosphaerella Johanson contains many pathogens capable of causin g a severe impact on the growth of susceptible eucalypt species. The lack o f knowledge about which species are present in Tasmania and their potential risk to the plantation industry prompted this study into the Mycosphaerell a species occurring on Eucalyptus globulus and Eucalyptus nitens plantation s in Tasmania. A total of 36 plantation and five road verge sites of E. glo bulus and E, nitens were sampled. Five Mycosphaerella Species and three spe cies from associated anamorph genera were isolated and identified in Mycosp haerella nubilosa, Mycosphaerella cryptica, Mycosphaerella tasmaniensis, My cosphaerella grandis, Mycosphaerella vespa, Coniothyrium ovatum, Sonderheni a eucalypticola and Sonderhenia eucalyptorum. The most frequently isolated species with the highest incidence and severity of infection were M. crypti ca and M, nubilosa. These two species appear to have the greatest potential to damage juvenile eucalypt plantations in Tasmania. A link between Mycosp haerella vespa and Coniothyrium ovatum is described for the first time.