Increased likelihood of sub clover red leaf syndrome in pastures

Farmers are reminded to keep watch for red leaf syndrome in their subterranean clover pastures this autumn.

Recent rainfall and warm temperatures in some parts of the south west may lead to conditions conducive for aphids to spread soybean dwarf virus (SbDV), which has been identified as a key contributor to sub clover red leaf syndrome.

Department of Primary Industries and Regional Development (DPIRD) senior research officer Paul Sanford said symptoms to look out for included red leaves, stunted plants and even premature plant death.

Farmers who suspect red leaf syndrome in their subterranean clover can access free testing by the DPIRD Diagnostic Laboratory.

“DPIRD and The University of Western Australia (UWA) are keen to test plants with symptoms as part of broader work to better understand this syndrome, which can severely stunt pasture growth,” Mr Sanford said.

“SbDV is not a seed borne virus but is spread by aphids. If growers can control the aphids there is a good chance they can manage the syndrome.

“Autumn control options include spraying for aphids using an anti-feeding insecticide at two and six weeks after sub clover seedlings emerge.

“Oats can also be sown as a barrier around pasture paddocks to disperse aphids and slow early spread into pasture from outside sources.”

This work is being done in collaboration with the Grains Research and Development Corporation project which is examining virus threats to the grain pulse industry.

More detailed information, including how to identify and manage the impacts of subterranean clover red leaf syndrome, is available from the department website agric.wa.gov.au search for ‘red leaf syndrome’.

Growers wishing to arrange free testing, can contact Mr Sanford at paul.sanford@dpird.wa.gov.au [1] or Kevin Foster of UWA at kevin.foster@uwa.edu.au [2]

Meat and Livestock Australia and Australian Wool Innovation are hosting an online Producer Survey which enables producers to report incidents and enable the livestock funding bodies to determine the extent of the problem. To contribute to the survey, go to the MLA website.

[3]

Red leaves and stunted plants are key symptoms of red leaf syndrome in subterranean clover.

Media contacts:

Jodie Thomson/Lisa Bertram, media liaison       (08) 9368 3937