Gangrene

Pathogen and disease type
Gangrene of potato is a fungal disease caused by the pathogen Boeremia foveata (formerly known as Phoma foveata). It is classified as a storage rot that primarily affects tubers. The pathogen is soil-borne and can survive in the soil or on infected plant debris, posing a constant threat to potato cultivation in many regions worldwide.

Host crops
The disease primarily affects potatoes. While other nightshade crops can occasionally harbor the fungus, potatoes remain the main host. The infection is primarily spread through the planting of contaminated seed tubers or by planting into infested soil, making clean seed selection a critical component of disease management.

Symptoms and signs
Symptoms on tubers appear as dark, circular, slightly sunken lesions on the skin. As the disease progresses, the internal tissue becomes light brown or greyish-brown and dries out. A characteristic sign of advanced gangrene is the formation of hollow cavities inside the tuber, often lined with fungal mycelium. The affected tissue remains relatively dry and hard, distinct from bacterial wet rots.

Conditions for development and severity
The development of the disease is favored by cool and damp weather conditions during the growing season. The greatest economic damage occurs during post-harvest storage, especially when potatoes are stored in conditions with high humidity and poor ventilation. Gangrene can significantly reduce the marketability of the crop, causing substantial losses in storage warehouses.

Control and prevention measures

• Use of certified, healthy seed tubers obtained from reliable sources.
• Practicing an appropriate crop rotation cycle (at least 3-4 years without potatoes).
• Ensuring careful handling during harvest to prevent skin injuries, which are entry points for the fungus.
• Adequate curing of potatoes immediately after harvest to heal wounds.
• Maintaining optimal storage conditions with effective ventilation and temperature control to inhibit fungal growth.