Results from this season’s wheat bulb fly survey have revealed a low risk from this pest, probably the lowest threat since 1984. The survey was primarily conducted in eastern and northern England where the threat is greatest.
Only one field of the 30 sampled was classified as high risk containing egg numbers greater than 250/sq m.
“It is likely that the cold wet weather had an impact on the number of adult flies and their ability to lay eggs,” said Caroline Nicholls, HGCA Research & KT manager.
“However, late-drilled crops, sown after November, or slow developing crops may still be at risk if they have only one or two tillers at the time of wheat bulb fly hatch in January/February. For these crops a lower threshold of 100 eggs/sq m is considered more appropriate,” she added.
Steve Ellis, ADAS entomologist who conducted the survey, added: “In the east of England, 47% sampled sites and 27% of the sampled sites in northern England were above the 100 eggs/sq m, in these situations, late-sown crops would benefit from an insecticide seed treatment.”
Anyone concerned about the pest should view the survey in full on the HGCA website and also the HGCA Topic Sheet 118, where there is useful information on control options.
Read more about cereal pests