Influence of Traditional and Dual-Use Cropping on Arthropods and Slugs in Soybean in Tennessee

Soybean is the number one agricultural crop in Tennessee for both number of hectares planted and economic value. Soybean, used in various products, is marketed globally. In recent years, Tennessee soybean growers have shown an increased interest in the use of cover crops with soybean. A cover crop is planted before the cash crop and can minimize some weeds, diseases, insects, and other pests. Traditionally, cover crops are terminated in the spring before cash crop planting. Traditional methods of cover cropping provide many benefits but can also produce some undesired results. Dual-use cover cropping is a newer method of cover cropping in which dual-purpose cover crops are harvested as a forage crop prior to planting the cash crop. Unfortunately, little research has investigated the impact of dual-use cropping on populations of insects and other arthropods, as well as slugs, in Tennessee.

A two-year study designed to evaluate the impact of dual-use cover cropping on pest and beneficial arthropods and slugs was initiated in east and middle Tennessee by using a five cover crop treatments and two management practices in soybean. The primary research goals of this project were to: 1) evaluate impact of dual-use cover cropping on pest and beneficial arthropods, 2) assess influence of dual-use cover cropping on density and impact of slugs, and 3) determine influence of dual-use cover cropping and pests on soybean yield. The results of this study have shown that management practice (i.e., traditional or dual-crop) did not have a significant (p≥0.05) effect on overall arthropod or slug densities. However, significant (p<0.05) differences were found between some of the cover crop treatments and arthropod densities. Management practice and cover crop treatment did not result in an increase in pest problems in soybean. Cover crop treatment and management practice also did not significantly (p≥0.05) impact soybean yield. Findings from this research should enable soybean growers to better understand cover crop-arthropod interactions to enhance soybean production in Tennessee. Further research on impact of plot sizes and insecticide seed treatment on insects and slugs may better define results and increase use of dual-cropped soybean.