Causal Agent:
Pythium spp. (Pythium aphanadermatum, P. ultimum, P. irregulare)
Susceptible Crops:
Affects all turfgrass, Geranium, Poinsettia, Snapdragon
Symptoms:
- Young seedlings collapse shortly after germination or are severely stunted and appear nutrient deficient
- Transplants and unrooted cuttings may develop a lower stem rot
- Infections on established plants cause lower leaves to turn yellow and defoliate
- Plants will wilt during the heat of the day, recovering at night
- Infected roots are soft, brown with a water-soaked appearance. The outer portion of the root is easily removed, leaving behind the stringy vascular core of the root
