Midge Pressure Should Bring About Variety Rethink

While the pest affects wheat crops to some extent every season, this year the pest has hit hard and the signs are that spray timings may have been awry.

According to independent variety consultant Mike Jeffes, typical 5-10% yield losses as a result of the midge grazing on grain and restricting grain development often go unnoticed.

However, HGCA trials suggest that in a bad year failure to spray or grow a resistant variety can reduce yields by 25%.

In 2004 it was estimated that well over 50% of the UK wheat crop had more than 5% grain damage.  And that was despite 25% of the crop having received a midge insecticide.

“Timing is everything,” he points out.  “But with only a day or so’s grace, growers struggle to get round their crops and often fail to hit the pest when it matters.”

Mr Jeffes points out that around 6% of UK wheat crop was estimated to have been lost to midge damage in 2004, and suggests that while we won’t know until the crop is in the barn, 2008 could be a repeat performance

Looking ahead, and based on maximum predicted market plantings, the area of resistant varieties likely to be sown this autumn could be as low as 25% of the UK wheat area.

While Oakley should secure a 12% market share and Viscount in its first year 4%, it is important that growers look to stick with varieties such as Robigus.

“Not only is Robigus the leading Group 3 wheat with a predicted premium potential of £10/t it’s a leading midge resistant type,” he points out. 

“Growers need to ensure they learn from the problems trying to keep WOBM at bay this season,” he says.  “There really only is one simple effective solution if we are to maintain high UK yields in a high pressure year and that is grow a resistant variety.”