A 120-day emergency authorisation has been granted for use of insecticide Biscaya (thiacloprid) for the control of peach potato aphids to prevent virus yellows infection in sugar beet.
The emergency authorisation, applied for by British Sugar and NFU, permits up to two treatments of Biscaya per crop at a maximum individual dose of 0.4l/ha.
BBRO head of science Dr Mark Stevens says use should be driven by awareness of aphids in crops and treatment thresholds.
“We have doubled the yellow water pan network this year to provide growers with advance warning. There are 60 evenly distributed throughout the four factory areas and catches will feed into an interactive map where sugar beet growers can view their three closest water pans simply by entering the farm postcode.”
Dr Stevens adds that as soon as the map shows winged aphids being caught in the locality it is time to monitor crops.
Dr Stevens urges growers to move quickly to control aphids at threshold: “If you are two days short of a herbicide timing, do not wait for the opportunity to tank-mix. Get the insecticide on immediately. We do not want secondary spread of virus within the crop, especially at early growth stages when virus yellows’ impact on yield is at its greatest.”
Based on an assessment of 10 plants per field:
The emergency authorisation states that Biscaya should be used in alternation with insecticides of a different mode of action.
To comply with the emergency authorisation and resistance management guidelines, Biscaya should be used first. If further applications are needed, follow with Teppeki (flonicamid) then switch back to Biscaya.