Use a super-wetter to enhance frit fly control

Growers seeking to reduce frit fly damage in winter wheat are being advised to include a suitable adjuvant to improve insecticide efficacy levels and reduce the chances of needing to re-drill crops.

Agronomists across the South East and West Midlands have reported frit fly damage to winter wheat crops sown after oats.

This week the Food Environment Research Agency (FERA) issued a warning highlighting the damage caused to crops in these regions.

“Almost all fields that have not had a broad-spectrum insecticide applied with glyphosate after winter and spring oats are now showing up to 10-20% frit fly larval invasion of main shoots; particularly prevalent in fields that have been min-tilled,” it said in its crop report for the South East.

For the West Midlands it simply stated that “damage is common in crops following winter oats”.

For most growers the preferred control option is likely to be chlorpyrifos, but trials have shown that efficacy rates can be improved dramatically with the inclusion of a super-wetter, such as Silwett-L77 from De Sangosse.

“Trials over successive seasons have demonstrated the improved performance of chlorpyrifos when combined with our full strength super-wetter Silwett-L77 at a rate of 0.1 litres/ha,” says De Sangosse commercial manager, Simon McMunn.

“Chloryprifos needs to penetrate deep into the stem of the plant at its base to control the frit fly larvae. The addition of Silwett- L77 has been shown to enhance this by dramatically reducing the surface tension of the spray solution to allow absorption deep into the centre of the plant’s tillers,” he adds.

Frit fly is a pest that can damage a range of cereals, grasses and maize. Crops particularly at risk are late sown cereals after grass and spring sown oats.

The FERA report can be found on the Crop Monitor website or by following the below link:

http://www.cropmonitor.co.uk/FoLCompiledReports/viewReport.cfm?week_id=207