It’s always tricky to predict insect pressure in the year ahead, and although wheat midge do require some soil moisture to emerge, it is only extremely dry spring conditions which will drastically reduce their numbers. This spring looks set to be anything but dry in Manitoba, but extreme moisture isn’t conducive to wheat midge either, so the situation may be similar to 2010, which saw a low incidence of infestation.
Moisture issues aside, wheat midge population levels in Manitoba seem to have tailed off, says MAFRI entomologist John Gavloski. He speculates beneficial parasites may be responsible.
“My gut feeling is that right now the parasites have the upper hand, so I am not expecting a very bad year for wheat midge in 2011,” he says.
The Alberta forecast shows an increase in wheat midge risk for the coming crop year. There are pockets of moderate to high midge risk through much of central and southern Alberta, and there is the risk that individual fields could have a high population even if the forecast in the area is low. Farmers throughout the midge area will need to monitor their fields carefully in 2011. For more information go to: http://www1. agric.gov.ab.ca/$ department/ deptdocs. nsf/All/prm13417
Saskatchewan also anticipates an increased threat from wheat midge for the upcoming growing season. The potential for economically damaging infestations to wheat crops is highest in the Dark Brown and Black soil zones. Central and Eastern regions of the province appear to have the highest midge populations and the highest risk of damage from the pest. However, there are areas of higher risk west of Saskatoon and south and west of North Battleford.
Actual populations will vary between fields and producers are encouraged to monitor wheat fields when the wheat head becomes visible as the boot splits until mid-flowering (anthesis). Areas of infestation indicating over 600 wheat midge per square metre may result in significant damage and yield loss. Farmers growing conventional spring wheat are advised to include the cost of insecticide application as part of their 2011 budget in areas indicating levels greater than 1,200 midge per square metre.
For more information go to http://www.agriculture.gov.sk.ca/Default.aspx?