Evaluating the spatial impact of soybean gall midge at the field level

Identified as a new species in 2019, soybean gall midge (SGM), Resseliella maxima Gagne, has the potential to cause significant injury in soybean fields. Yield losses of up to 100% for the first 30 m of the field edge have been reported under heavy infestations. Field and greenhouse observations have shown that SGM lays eggs in naturally occurring fissures at the base of the soybean stem. Hilling, a management strategy that covers fissures with soil, has been studied and reported to reduce SGM infestation and yield losses. However, little is known about the spatial impact of SGM within the field. As a result, a field study with three replications is being conducted in eastern Nebraska. The objective of the study is to understand the efficacy of hilling compared to the no-hilling up to 152 m from the field edge. SGM larval abundance, frequency of infested plants, plant injury, and yield will be taken from 15 different distances from the field edge for each treatment. The results from this study will help farmers to understand the spatial impact of SGM to estimate areas where treatments may be needed as well as hilling as a potential strategy to manage SGM and reduce yield losses.