damping off on Tomato
Quick answer
If your Tomato has damping off, the most likely cause is: Seedling damping-off (Pythium spp., Rhizoctonia solani, Fusarium spp.) occurs when pathogenic fungi infect seedlings at or below soil line. Fungi colonize root cortex and vascular tissue, producing phytotoxins and enzyme cocktails (cellulases, pectinases) that degrade cell walls, causing water transport collapse leading to sudden wilting and death.
Start here:
- 1. 1. Sterile medium: Use commercially sterilized seed-starting mix or amend garden soil with 50% perlite:50% peat for drainage; do not reuse old seed-starting mix without sterilization (steam at 82°C for 30 min)
- 2. 2. Spacing: Sow seeds thinly to avoid dense seedling clusters that trap humidity; ideal density is 60-80 seedlings per 10x10cm tray
Why Tomato gets damping off
Seedling damping-off (Pythium spp., Rhizoctonia solani, Fusarium spp.) occurs when pathogenic fungi infect seedlings at or below soil line. Fungi colonize root cortex and vascular tissue, producing phytotoxins and enzyme cocktails (cellulases, pectinases) that degrade cell walls, causing water transport collapse leading to sudden wilting and death.
How to reverse damping off on Tomato
- 1
1. Sterile medium: Use commercially sterilized seed-starting mix or amend garden soil with 50% perlite:50% peat for drainage; do not reuse old seed-starting mix without sterilization (steam at 82°C for 30 min)
- 2
2. Spacing: Sow seeds thinly to avoid dense seedling clusters that trap humidity; ideal density is 60-80 seedlings per 10x10cm tray
- 3
3. Water management: Apply water from below (tray bottom-watering) rather than overhead; keep substrate moisture at field capacity (50-60%), not saturation; water in morning to allow surface drying
- 4
4. Biocontrol: Incorporate Trichoderma harzianum at 5g/L medium or drench at 1x10^6 CFU/mL at seed emergence to competitively exclude damping-off pathogens
- 5
5. Fungicide treatment: For high-risk conditions, apply metalaxyl or mefenoxam as drench at 0.5mL/L at first true leaf stage; organic alternative: copper octanoate at 2mL/L
Keep damping off off this Tomato
Use sterile seed-starting mix (not garden soil); avoid overwatering by maintaining substrate at 50-60% moisture (not saturated); provide good air circulation; apply Trichoderma harzianum biocontrol at 1x10^6 CFU/g to colonization prevention.