Efficacy of washing to remove cysts of Globodera rostochiensis from potato cv. Trent tubers from peaty clay soil

Globodera rostochiensis (potato cyst nematode, PCN) is a serious pest of quarantine concern because its eggs, protected within cysts, are long lived and are readily transported in soil adhering to potato tubers or, less commonly, as cysts that develop directly on the tuber. The experiments in this study showed that all PCN cysts were removed from tubers of potato cv. Trent harvested from land infested with PCN when they were washed until less than 5% of tubers retained small visible soil patches. It was concluded that tubers washed to this standard would have an acceptably low risk of carrying cysts of PCN on potatoes for processing. However, more data are needed for a range of soil types as the only currently known infested soil in Australia is a peaty clay.