Southern Blight of Soybean
scouted Aug. 24, 2025
- Scientific Name
- Sclerotium rolfsii
- Background
- Soybeans in Brunswick County were being scouted, and it was observed that 50% of the field was affected by defoliation on most of the lower leaves and the newly developed pods. There could have been water standing in the field at some point during the season. A sample was submitted to the PDIC for diagnosis.
- Conclusion
- Southern blight of soybean, also known as southern stem rot, was identified as one of the diseases affecting this field. It's usually not a common problem in North Carolina, but it can locally cause damage when environmental conditions (hot and wet) are conducive to disease. This disease is caused by Sclerotium rolfsii, a fungus that produces sclerotia (overwintering structures) that can survive in the soil for long periods of time. When wet, warm conditions are present, sclerotia germinate, and the hyphae invade the host just below or at the soil line. Initial symptoms include yellowing, wilting, and light brown lesions on the stem
- Resources
