D3206: The impact of soybean planting depth on soybean gall midge (Diptera: Cecidomyiidae) infestation and plant injury

Soybean gall midge (Resseliella maxima Gagné) was recently identified as a new species causing significant injury to soybean. Currently, soybean gall midge larvae have been found in seven midwestern states (NE, IA, SD, MN, MO, ND, and KS). Studies have shown that infestation depends on the presence of fissures that develop at the base of the soybean plant around the V2 growth stage. Field observations indicate that these fissures are only present below the cotyledonary node or in an area within 3–5 cm above the soil surface. As a result, a field research project was conducted in eastern Nebraska to understand the impact of soybean planting depth on infestation and injury from soybean gall midge. Soybean was planted at three different depths (1.2 cm, 3.8 cm, and 6.4 cm) at several locations in eastern Nebraska. To evaluate its impact on soybean gall midge infestation, the frequency of infested plants, larval abundance, plant injury score, and yield were recorded. The results of this research will provide an understanding of the impact of different soybean planting depths on fissure exposure above the soil surface and their relationship to soybean gall midge infestation.