May 9, 2002

Infected plants surviving over summer is the primary inoculum source of beet western yellow virus (BWYV).

When spread very early in the growing season, BWYV causes significant seed yield loss in canola in Western Australia.

Aphids spread the virus by moving into canola crops after feeding on infected plants, especially wild radish.

Researchers, supported by the Grains Research & Development Corporation, are therefore developing a predictive model and decision support system (DSS) to forecast aphid build-up and BWYV transmission and are investigating insecticide control of virus spread.

The DSS will allow efficient targeting of insecticides to avoid unnecessary and costly prophylactic use, reduce the likelihood of insecticide resistant aphid populations building up and provide an environmentally responsible approach to control.

Data has been collected from different rainfall zones to ensure the model accurately forecasts aphid arrival and numbers and virus spread at different locations over a range of seasons.

Contact: Debbie Thackray, Tel 08 9368 3754 or Roger Jones, Tel 08 9368 3269