Soybean stem borer
scouted Oct. 15, 2024
- Scientific Name
- Dectes texanus
- Background
- Soybeans in Brunswick County, variety Revere 4821 XFS, were planted using 120 bags. Yields across the field ranged from 65–80 bu/A, except for a 7.8-acre section. This area is surrounded by trees and houses, although in previous years it has produced good yields of soybeans and other crops. Normal herbicide and insecticide treatments were applied, and the crop appeared healthy at desiccation. However, when moisture was checked, it was observed that the pods contained no beans. The soybeans looked normal throughout the season. A plant sample was collected for further evaluation.
- Conclusion
- It was found that the stem showed signs of Dectes stem borer, also known as soybean stem borer. Soybean stem borers have one generation a year and are active from May through early October. It usually causes indirect yield loss due to lodging or an interaction with other negative environmental conditions, such as drought. These insects are usually more abundant in field edges near weeds or fields adjacent to last year's soybeans. There is no economic threshold for it, but good cultural practices and timely harvest can limit its impacts.
- Resources
