Pythium root and crown rot

scouted April 16, 2026

Scientific Name
Pythium sp.
Background
A tobacco greenhouse (Variety NC 960) was being scouted, and it was observed that 20% was affected by yellowing, damping off, and root rot. It was observed that it started from 1-2 trays but spread to adjacent trays. A sample was submitted to the PDIC for diagnosis.
Conclusion
The issue was identified as Pythium root rot. Pythium root rot will cause severe stunting and yellowing, and it thrives in warm, humid conditions. Some of the things that can help are: increasing air circulation to reduce humidity in the greenhouse, sanitation of trays and equipment, as well as proper disposal of clippings, which can also help reduce the risk of disease. Terramaster4EC is labeled to prevent or rescue plants from further Pythium root rot development.
Resources
Tobacco greenhouse float trays showing signs of damping off
Close-up of tobacco seedling in a float tray showing signs of damping off

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