Abstract
Worldwide Phytophthora diseases have significant direct and indirect impact on flora and fauna. In south-west Western Australia approximately 41% of the 5710 described plant species across a large number of plant families are susceptible to P. cinnamomi a pathogen listed as ‘a key threatening process’ to Australia’s biodiversity by the Commonwealth Government. P. cinnamomi in Western Australia is considered a ‘Biologial Bulldozer’ because of its ability to permanently change the structure and function of plant communities and the species they support. Through anthroprogenic activities this introduced exotic pathogen and related species are now widely distributed and many unique plant community types are now infested or threatened. Concerted effort is now spent on mapping its occurrence, identifying areas that are pathogen-free, considered protectable in the medium to long-term and have high conservation value. This presentation will discuss the biology of Phytophthora as a genus and what makes them such devastating plant pathogens, the methods used to diagnose and map their occurrence and the procedures used to select ‘protectable’ communities of high value. Case studies will be used to discuss the impact of the pathogen on plant communities in terms of floristics and habitat change and how this in turn impacts on native fauna and ecosystem function. Control strategies including communication, hygiene implementation measures, the aerial application of phosphite and the use of eradication techniques for spot infestations will be also be discussed with regards to their benefits and possible detrimental effects to native plant communities.