Warning on aphids

Agricultural departmental officials are urging western Victorian canola growers to look out for green peach aphids in crops favourable to turnip yellows viris.

Agriculture Victoria research scientist Piotr Trebicki issued the warning after observing green peach aphids and the virus, previously known as beet western yellows virus, in paddocks south of Horsham.

“The volunteer plants and weeds that sprung up following late summer and early autumn rain provided good conditions for aphid populations to increase,” he said.

The virus, spread by the green peach aphid, can cause significant yield losses in canola and pulse crops.

“If transmitted to canola or other crop species at an early growth stage it can cause total crop losses,” Dr Trebicki said.

“Infection at a later growth stage has a less severe impact on canola and most pulses, however chickpeas are very vulnerable to infection at any growth stage.”

Typical symptoms of turnip yellows virus include stunted plant growth and leaves showing a yellow or purple discolouration.

A recent Agriculture Victoria virus survey showed an increase in turnip yellows virus, particularly in paddocks where summer weeds, self-sown canola and spring-sown canola were growing.

Dr Trebicki said the risk of infection increased when crops were sown in, or next to, paddocks that hosted large aphid populations or where the virus was already present.

Farmers seeking more information can visit website agriculture. vic.gov.au.