A preliminary assessment of high risk areas for Puccinia psidii (Eucalyptus rust) in the Neotropics and Australia

Puccinia psidii Winter, which causes both guava rust and eucalypt rust, is an important pathogen on eucalypts and other members of the Myrtaceae famil y in the Neotropics. If introduced into Australia it could represent a majo r potential threat to eucalypt plantations as well as native vegetation. Ob servations of the distribution of eucalypt rust epidemics in the Neotropics were analysed to develop a simple description of the species climatic requ irements. Climatic mapping programs were used to generate maps showing high risk areas in the Neotropics and Australia. It is concluded that some nort hern parts of the Northern Territory as well as eastern coastal areas of no rthern New South Wales and Queensland are the regions most at risk to P. ps idii in Australia. However, it is recognized that more detailed models and survey information are needed to provide better predictions of epidemic ris ks. (C) 2000 Elsevier Science B.V. All rights reserved.