Saddle gall midge

The saddle gall midge (Haplodiplosis marginata) is a significant agricultural pest belonging to the order Diptera, family Cecidomyiidae. It is known for causing localized tissue swelling on the stems of cereal crops, which severely impacts plant development and grain yield.

The primary hosts for this pest include wheat, barley, and rye. Although it primarily attacks cultivated crops, wild grasses can sometimes harbor populations, serving as a bridge between seasons. Wheat fields, in particular, are at high risk during the stem elongation stage.

The biological cycle is univoltine, meaning there is only one generation per year. Larvae overwinter deep within the soil profile. In the spring, they pupate, and adult midges emerge to coincide with the rapid growth phase of the host cereals. Female midges lay eggs on the upper surface of the leaves, which then migrate to the stems.

The damage is caused by larvae feeding on the stem surface, which triggers the plant to form characteristic saddle-shaped galls. These galls interfere with nutrient transport, leading to stem bending, reduced grain filling, and increased susceptibility to lodging. In severe infestations, the entire crop quality is compromised.

Management strategies rely heavily on crop rotation and soil cultivation. By interrupting the midge's host availability and burying pupae through deep plowing, farmers can significantly reduce the local population. If threshold levels are reached, the application of chemical insecticides should be timed during the egg-laying period.