Phylogeny, pathogenicity and epidemiology of potato spindle tuber viroid (PSTVd) and related pospiviroids in Australia - Final Report

Potato growing areas of Australia are currently considered free of Potato Spindle Tuber Viroid (PSTVd) and this pathogen is classified as an emergency plant pest (Category 3) under the Emergency Plant Pest Response Deed (EPPRD). There were six emergency responses for PSTVd in Western Australia (WA) and New South Wales (NSW) in the six years preceding commencement of this project and the concern was that without any pathway control there would continue to be periodic detections of PSTVd in the future. The importation of tomato seed, which until June 2008 was unregulated, had been implicated as the likely source of PSTVd. However, research at that time from Europe identified alternative hosts of PSTVd as potentially the source of inoculum for PSTVd infected tomatoes. Moreover, research then in WA indicated that both solanaceous and non-solanaceous species might be hosts.