Phoma is a dark-colored dry-rot fungus.

recognize gangrene of potato
Gangrene of potato, photo: Svarði2 - CC BY-SA 4.0

Gangrene (Phoma exigua var. foveata) is a dark-colored dry-rock fungus.
Occurs mainly in storage and preservation (potatoes). The fungus survives in the soil and from that’s where the infection starts.

Where to find


Seed potatoes may have become infected by residual fungus in boxes. Remove infested potatoes.


Careful harvesting: avoid damaging the potatoes. These form the entries for fungus such as Phoma.
Plant resistant potato varieties.
During the first weeks of storage, keep the temperature at 9°C, this promotes the healing (corking) of the wounds. Any infection with Phoma is encapsulated by the cork of the wound.