Grains Research and Development Corporation (GRDC) supported research into developing a wheat streak mosaic virus (WSMV) seed test has taken on a new importance after the disease was found throughout the Western Australian wheatbelt.

The Department of Agriculture and Food, Western Australia (DAFWA) is developing the seed test, which should be available in time to test samples from 2006 harvested seed.

GRDC Crop Protection Manager John Sandow said although the epidemiology of the disease was still poorly understood, avoiding sowing contaminated seed may greatly assist disease management.

The ability to detect the disease in bulk seed samples could therefore be an important tool for minimizing WSMV damage in wheat crops.

He said the virus could already be detected in small samples and a bulk seed test was now well on the way.

“DAFWA is now optimising and scaling up the procedure for testing bulk seed samples and hopes to have a test available by the end of the year,” Mr Sandow said.

Overseas experience suggests chemical control of the WSMV vector is unlikely to be effective and with the WSMV resistance status of Australian wheat varieties uncertain, developing the seed test is a priority.

The only other strategies recommended to help avoid WSMV were to destroy a green bridge and avoid sowing early when temperatures favoured mite activity.

Mr Sandow said growers in the Merredin area had indicated considerable interest in using the testing service when available.

It is likely WSMV entered the Merredin area through the sowing of infected seed.

When the seed test is available, growers will send seed samples to AGWEST Plant Laboratories.

According to DAFWA, locations with positive WSMV detections as at September 25 include Dongara, Wongan Hills, Goomalling, Quairading, Kellerberrin, Koorda, Trayning, Burracoppin, Moorine Rock, Merredin, Hyden, Narembeen, Karlgarin, Corrigin, Nyabing, Lake King and the Esperance area (Gibson, Scadden and Yerritup).