Causal Agent: 

Oomycete (Pythium spp.)

Characteristic symptoms:
 
The part of the stem near the soil surface turns brown, becomes water-soaked, soft and slender and then collapses.
 
Young seedlings topple down due to root rotting and weakened stem.
 
In pre-emergence damping-off, germination of seed is greatly reduced.
 
Conditions for Disease Development:
 
The disease is common in cool, wet soils.
   
All crops are susceptible usually at seedling (3 weeks after sowing) or early vegetative stage.
   
Over watering or poor drainage, over crowding of plants, excessive application of nitrogen, stressful environmental conditions and presence of nematodes may contribute to susceptibility.
   
The pathogen is disseminated through contaminated irrigation water, splashing rain or heavy rainfall.
   
Management and Control:
 
Use disease-free seeds and seedlings.
   
Drench nursery beds with captan fungicide.
   
Clean thoroughly seedling trays and pots and soak in 10% household bleach (chlorox).
   
Use disease-free or sterile soil media for raising seedlings.
   
Avoid over watering or excessive moisture and other stressful conditions that may predispose seedlings to damping-off.
   
Avoid contact with ground soil or other sources of contamination.
   
Check irrigation ponds regularly as this may be a source of fungal contamination.
   
Expose beds to solar radiation to minimize fungal population.
   
Drench seedlings with chemical fungicides like promocarb hydrochloride (e.g. ProplantⓇ, PrevicureⓇ) or fosetyl aluminum (e.g. AlietteⓇ), metalaxyl+mancozeb (e.g. Ridomil Gold MZ 68 WGⓇ, Apron XL 350 ESⓇ), mancozeb (e.g. Attain M-80Ⓡ, Achem Mancozeb 80 WPⓇ, Micron 80 WOⓇ, VanzebⓇ)  before symptoms develop.
 

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