Western Australia’s potato fresh market, processing and export industries are benefiting from a virus testing program implemented by the Western Australia Department of Agriculture and Food’s seed certification and diagnostics service.

AGWEST Plant Laboratories Manager Mark Holland said the program targeted all generation two sown certified and registered seed potato crops for the presence of potato leaf roll virus, tomato spotted wilt virus, potato virus S, potato virus X and potato virus Y.

The testing program was implemented in 1997 on generation 1 sown certified seed. Since then the program has progressively been expanded into registered seed, and targeted further down the production chain.
The testing programme is funded by the Agriculture Produce Commission, Potato Producers Committee.
“It was implemented because visual inspection failed to identify virus in various circumstances. Some viruses may not produce symptoms in the year of infection, while others show up only periodically,” Mr Holland said.

“Since we began the testing programme, virus levels have declined in the State’s seed potatoes. Users of certified and registered seed are now far less likely to receive seed potatoes infected with significant levels of virus,” Mr Holland said.

“We have included potato virus Y in the testing programme. It is not yet established in Western Australia, but outbreaks have been found in tomato and potato crops in the past decade. It is a serious disease of potatoes elsewhere, so it is important we test for it to ensure it does not gain a hold here.”

Mr Holland said some seed growers were finding significant levels of virus when the program started.

“Test results were collated per seed grower and circulated. It was very pleasing to see those growers with higher virus levels respond to the information and improve their performance. All seed growers are now producing very good results,’ Mr Holland said.