Saddle gall midge is a sporadic pest, which usually persists at low population levels. Yield loss can be caused by constricted vascular supply to the ears as a result of larval feeding and by lodging of gall-weakened stems in high winds.
Saddle gall midge (SGM) is a sporadic pest that can impact on cereal yields.
Mature SGM larvae fall off stems in July, seek refuge in soil and enter diapause (suspend development).
From April onwards, the larvae pupate and adult midges, typically, emerge in May.
After mating, blood-red eggs are laid on both the upper and lower surface of cereal and grass leaves.
Eggs hatch within a couple of weeks and the larvae feed on the stem underneath the leaf sheath.
The feeding results in characteristic saddle-shaped galls, which are often covered by the leaf sheath. More apparent symptoms, therefore, are seen as uneven contours on the stem surface.