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Root and Cutting Rots

Phytophthora spp. and Pythium spp.

26 host plants

Last updated

Data Coverage 3 of 6 dimensions
Causal Agent
Host Plants
Symptoms
Management
GDD Threshold
Regional Notes

Root and cutting rots cause decay of roots and propagation material, particularly in wet conditions. Improve drainage in growing areas. Avoid overwatering. Use well-drained growing media. Remove infected plants immediately. Select pathogen-tested propagation stock. Proper drainage and good site selection are critical to prevent root disease problems. Monitor plants for early signs of decline or wilting Early detection and prompt management of symptoms help limit disease spread.

Root rots thrive in waterlogged soil, so drainage is your most important intervention. Avoid overwatering and ensure the planting site drains well. Remove severely affected plants to prevent spread to neighbors through root contact or contaminated soil. When replanting, choose resistant species or improve soil structure before putting anything back in the ground.

Quick Reference

Causal Agent
Phytophthora spp. and Pythium spp.
Host Plants
26
Favorable Conditions
Overwatering; poor drainage; contaminated propagation media; recycled irrigat...

Management

What Triggers Infection

Overwatering; poor drainage; contaminated propagation media; recycled irrigation water; warm temperatures for Pythium, cool for some Phytophthora spp.

Cultural Controls

  • Use tissue cultured plants (if possible) to avoid the problem altogether. Take cuttings from field plants above the splash zone. Rain and irrigation can splash soil particles as well as microorganisms onto plants. Do not take cuttings from obviously or subtly diseased plants. Take cuttings in the morning and/or after irrigation when they are more f

Host Plants (26)