Soft Rot
Erwinia carotovora subspp. atroseptica
Pathogen
Bacterium
Hosts
Potatoes
Symptoms
The tuber phase of blackleg. Tubers may exhibit varying degrees of decay, with the black rot generally extending from the heel end.
Development
Daughter tubers are primarily infected by bacteria from rotting seed tubers before harvest or from contaminated machinery at harvest. Healthy tubers can also be infected through wounds and lenticels (breathing pores) during storage with diseases tubers.
Favourable Factors
Wet soil and mechanical injury during harvest or poor ventilation during storage.
Importance
Severe storage losses
Control
There are no known resistant varieties, but less susceptible varieties include Pentland Crown, Pentland squire and Cara
Avoid planting or cutting infected seed tubers
Avoid lifting under wet conditions
Rotting tubers should be collected and destroyed
There is no satisfactory chemical treatment