Wheat streak mosaic virus under scrutiny across wheat belt

NSW Department of Primary Industries researcher, Dr Steven Simpfendorfer, sows the trial near Coolah to test the resistance of commercial wheat varieties to wheat streak mosaic virus.
NSW Department of Primary Industries researcher, Dr Steven Simpfendorfer, sows the trial near Coolah to test the resistance of commercial wheat varieties to wheat streak mosaic virus.

Recent rain has allowed crucial research into the potentially devastating wheat streak mosaic virus (WSMV) to go ahead.

NSW Department of Primary Industries staff are running trials and monitoring crops throughout the State in a bid to reduce the impact of WSMV.

First detected in NSW just three years ago the virus has been found in all wheat growing areas of the State and last year cut yields of some early wheat crops in the Central and South West slopes by up to 80 per cent.

In resistance trials sown last week near Coolah NSW DPI researcher, Steven Simpfendorfer, is testing risk levels of commercial wheat varieties including durum wheat.

“We basically don’t have any solid data on how the virus will impact in Australian conditions and we aim to generate that information through this trial and supporting research,” Dr Simpfendorfer said.

“Oats, barley and triticale were also planted and while we don’t expect them to be as susceptible to WSMV, this trial will confirm their resistance levels.

“From our research we plan to develop information growers can use next year and give them some indication of the best options.”

NSW DPI agronomists are continuing to monitor this season’s wheat crops and growers who find the virus have been advised to contact their local agronomist.

Wheat streak mosaic virus on wheat plant. <br />(Photo: Jan Edwards)
Wheat streak mosaic virus on wheat plant.
(Photo: Jan Edwards)

Another target of the WSMV trial is the wheat curl mite which is responsible for spreading the virus.

According to Dr Simpfendorfer the virus can’t spread without the presence of the mite.“Wheat curl mites need what we call a green bridge to reach crops. Spraying out any volunteer wheat and grass around the edge of your crop will reduce the likelihood of those mites moving into your crop,” he said.

“We are testing chemical controls on the mite. USA data indicates that insecticides just don’t work on the wheat curl mite but we need to confirm that a similar situation exists here.”

Early sown wheat crops are more susceptible to infestation by wheat curl mite because they are planted when the mites are active.

The mites thrive in temperatures ranging from 24 to 28 degrees Celsius becoming dormant once temperatures drop below 10 degrees Celsius.

With additional funding from the Grains Research and Development Corporation research into the management of WSMV and the wheat curl mite is supported by NSW DPI laboratory trials in Wagga Wagga and Tamworth and field trials at Coolah, Young, Nangus and Ganmain.