The Department of Primary Industries and Regional Development (DPIRD) has issued a reminder to farmers to keep watch for red leaf syndrome in their subterranean clover pastures this autumn.
Science Officer with the Department, Paul Sanford said recent rainfall and warm temperatures in some parts of the south-west might lead to conditions conducive for aphids to spread soybean dwarf virus (SbDV), which had been identified as a key contributor to sub-clover red leaf syndrome.
“Symptoms to look out for include red leaves, stunted plants and even premature plant death,” Mr Sanford said.
“Farmers who suspect red leaf syndrome in their subterranean clover can have free access to testing by the DPIRD Diagnostic Laboratory.”
He said the DPIRD and The University of Western Australia (UWA) were keen to test plants with symptoms as part of broader work to better understand the syndrome, which could severely stunt pasture growth.
“SbDV is not a seed-borne virus but is spread by aphids,” Mr Sanford said.
“If growers can control the aphids there is a good chance they can manage the syndrome,” he said.
“Autumn control options include spraying for aphids using an anti-feeding insecticide at two and six weeks after sub-clover seedlings emerge.”
He said oats could also be sown as a barrier around pasture paddocks to disperse aphids and slow early spread into pasture from outside sources.
The work is being done in collaboration with the Grains Research and Development Corporation project which is examining virus threats to the grain pulse industry.