Poster: Epidemiology: Pathogen Dispersal
Teratosphaeria pseudoeucalypti: an emerging pathogen with uncertain impact on Eucalyptus plantations
C. PEREZ (1), G. Balmelli (2), S. Simeto (2), E. a (3), M. Codina (3), R. Garcia (3), N. Ramirez (3), O. Bentancur (3), M. Wingfield (4) (1) EEMAC, Universidad de la Republica, Uruguay; (2) INIA Tacuarembo, Uruguay; (3) EEMAC, Universidad de la Republica,
Teratosphaeria pseudoeucalypti was first discovered in Queensland, Australia in 2010 causing a serious leaf blight disease known as Kirramyces Leaf Blight (KLB) on Eucalyptus commercial plantations. The pathogen was subsequently reported in 2014 in Argentina, Brazil and Uruguay, representing the first occurrence outside Australia. During 2015, a survey was conducted to assess prevalence, incidence and severity of KLB on Eucalyptus camaldulensis and E. tereticornis in Uruguay. A total of 80 plantations were visited, including these species and their hybrids. In each plantation, one transect of 20 trees in a row was scored for crown damage, based on percentage of defoliation and overall disease severity. The disease was found in all regions of the country. There was no clear pattern of distribution or severity of the disease with a distribution appearing to be generalized. Classification and regression tree analysis indicated that host species was the most important segregating factor based on severity, were E. tereticornis plantations showed a significantly lower severity than E. camaldulensis and their hybrids. KLB is widespread and serious on susceptible Eucalyptus spp., posing a threat to commercial plantation forestry in Uruguay. Future studies will concentrate on understanding the genetic diversity of a large collection of isolates that have emerged from this study and on selecting planting stock resistant to KLB.