Soybean gall midge

The soybean gall midge (Resseliella soya) is a member of the order Diptera and the family Cecidomyiidae. It is an economically significant pest specifically associated with soybean cultivation, causing yield losses in various agricultural regions where soy is a primary crop.

The host plant is primarily the soybean (Glycine max). The insect prefers the lower portion of the soybean stem, where larvae feed on the subepidermal tissues. This specialized feeding behavior causes direct damage to the plant's structural integrity and its ability to transport nutrients and water from the root system.

The life cycle of the soybean gall midge involves a diapause stage during the winter, typically spent as larvae in the soil or crop residue. As temperatures rise, the insects pupate and emerge as adults. Throughout the growing season, multiple generations can occur, leading to overlapping life stages and continuous pressure on the crop.

The damage caused by Resseliella soya is characterized by stem discoloration, cracking, and necrosis near the soil surface. Severely infested plants often show signs of wilting, premature yellowing, and eventually lodging. This destruction of the vascular tissue severely limits seed filling and overall crop productivity.

Integrated pest management (IPM) is essential to mitigate the damage caused by this midge:

• Crop rotation to reduce the overwintering population density in the soil.
• Proper disposal of infested crop debris through tillage or other sanitation practices.
• Use of certified, resistant, or tolerant soybean varieties where available.
• Regular field scouting to detect early signs of midge activity at the base of the stems.
• Strategic insecticide application focused on the early stages of adult emergence.