Rhizoctonia root rot
scouted April 15, 2026
- Scientific Name
- Rhizoctonia solani
- Background
- A tobacco greenhouse was being scouted and it was observed that 30 % was affected by localized damping off and browning. A sample was submitted to the PDIC for diagnosis.
- Conclusion
- The issue was identified as Rhizoctonia root rot. This disease is caused by the soil-borne fungal pathogen Rhizoctonia solani, a species complex that includes several anastomosis groups, with AG2-2, AG3, and AG4 affecting tobacco. In the greenhouse, Rhizoctonia solani causes damping off, which affects seed germination and can cause seedling collapse. Affected stems and roots will have sunken brown lesions in them. The pathogen can survive in soil and crop debris, and disease development is favored by warm and humid conditions. Variety resistance has not been assessed for this disease. Management of target spot relies on a combination of cultural practices and chemical controls.
- Resources
