Charcoal rot
scouted July 16, 2026
- Scientific Name
- Macrophomina phaseolina
- Background
- A soybean field in Union County was being scouted, and it was observed that 25 % of the field was affected by yellowing between the veins, in patches across the field. The field is a dry and sunny site. A sample was submitted to the PDIC for diagnosis.
- Conclusion
- The issue was identified as charcoal rot of soybean, caused by Macrophomina phaseolina. It starts out with patches of stunted or wilted plants, and while the infection can happen very early in the season, the symptoms usually appear after flowering or when plants become stressed. It usually does not represent a major threat to production in the state. Crop rotation to non-host crops may help limit survival of the fungus in soils, and drought stress mitigation, when needed, may limit the severity of disease symptoms.
- Resources
