Wheat bulb fly hatch underway in Yorkshire

UK - February 07, 2008

Mild weather has encouraged early wheat bulb fly hatch in most areas according to Dow AgroSciences. 

Dow AgroSciences Pestwatch, which monitors susceptible sites in East Anglia and Yorkshire, shows that egg hatch is now averaging 16% at the five sampling sites.  Even the Yorkshire site has started and is at 12.5%. Although there is no sign yet of plant invasion growers should check for signs of damage, as the best time to treat is around 15% egg hatch. 

Yorkshire-based, Reuben Morris, technical director at distributor Cropwise warns: “Risks will be greatest after poor sugar beet crops, especially where water logging restricted top growth. This gave adult flies better access for laying eggs.  We are now on the look out for wheat bulb fly and making recommendations where treatment is needed.”  

A Risk Assessment Chart can be used to identify high risk fields and check for signs of wheat bulb fly damage. If there is a problem, and ground conditions permit, then Dursban WG (chlorpyrifos) should be applied at 1.0 kg/ha in 200 to 1,000 litres of water a hectare as soon as practical. 

Dursban WG can be applied to frosty ground but should not be tank mixed. Dursban WG must not be applied in tank mix with Atlantis WG, regardless of weather conditions. An interval of 14 days must be observed between applications of Dursban WG and Atlantis WG.