Soybeans were scouted at the R5 growth stage and wilt, plant death, and leaf discoloration was observed in strips along rows and patches across the field.
Conclusion
This issue was confirmed by the NC State Plant, Disease and Insect clinic to be Charcoal Rot, caused by Macrophomina phaseolina. Charcoal rot is soil and seed borne fungus that favors dry, stressed conditions. Symptomology associated with charcoal rot can include brown spots on cotyledons, red/brown circular lesions on leaves that turn dark brown/black, and light brown/grey lesions on stems. No-till environments or irrigation are cultural practices recommended to preserve or increase soil moisture. Fungicides are not typically recommended for managing charcoal rot. Varietal resistance is an important factor in managing Charcoal rot.