Potato Wart: A Fungal Disease of Tubers

This soil borne disease of potatoes is caused by a fungus called Synchytrium endobioticum. The disease appears appers mainly on stolons and tubers. Symptoms on above ground growth are not often visible. Young potato Warts are white in colour, soft and pulpy in texture darkening and and decaying as they age.

Synchytrium endobioticum loves wet conditions. It produces a thick walled structure known as a winter sporangium which can remain viable for up to 30 years. It can survive at depths of 50 cm in the soil. In spring, at high temperature and moisture, overwintering sporangia germinate to release mobile zoospores which infect suitable host cells. The infected plant cells swell, divide and surround the dividing zoospores resulting in the wart.

Infected seeed tubers, infected soil, machinery and implements used in infested potato fields and potato cultivation, footwear, and manure from animals that have fed on infested tubers can spread this disease.