Causal Agent:
Phytophthora erythroseptica
Biology:
Pathogen of potato and many other plants; present in many soils worldwide; tuber infection and decay is worst in warm and excessively wet soils.
Dispersal:
Infection can spread from tuber to tuber during harvest and handling. Infected seed can also spread the disease.
Fungicide Resistance:
P. erythroseptica has begun to demonstrate resistance to fungicides. Fungicides should be rotated frequently to prevent resistance.
Management:
Further Reading:
Pacific Northwest Pest Management Handbooks