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

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