The Canadian Food Inspection Agency has confirmed a case of potato wart in a Prince Edward Island field.

In an email to CBC News, CFIA said the field has been placed under quarantine, with the full cooperation of the grower, to prevent the risk of spreading the fungus. The agency has not indicated where the farm is located.

Potato wart poses no risk to humans or food safety, but it can be a serious disease for the infected potatoes, which become disfigured.

It also prevents tuber production and can affect export markets.

CFIA indicated it is sampling material from the field affected to determine the extent of the infestation. Staff are also tracking movement on and off the farm to see if any other fields have been infected.

Potato wart was last found in P.E.I. two years ago.

The soil-borne fungus shut down trade between P.E.I. and the United States when it was first found on the Island, 14 years ago.

Since then new protocols for monitoring and controlling the spread of potato wart have been introduced.

The discovery of potato wart comes on the heels of another blow to the industry---the decision of McCain Foods to close its Borden-Carleton plant.