(Nov. 21) Canada, following the United States’s lead, will launch its own nationwide hunt for the mop top potato virus.

The move comes after 15 cases of mop top were found in four Canadian provinces, including one on Prince Edward Island. The national testing program, set to begin Nov. 19, will test 3,000 potatoes from each of Canada’s provinces. The U.S. began a similar survey in October.

“I think it’s a positive step,” said John Keeling, executive vice president and chief executive officer of the National Potato Council, Washington, D.C. “We continue to believe that we can get the testing done by early December and decide what an appropriate management level for mop top is.”

This summer, Canada restricted potato exports from 11 U.S. states — including Idaho and Washington — that it suspected of having mop top-infected potatoes. The restriction came after the U.S. Department of Agriculture’s Animal and Plant Health Inspection found mop top on a Maine research farm in August. In September, three states — California, Delaware and New Jersey — were dropped from the CFIA list, after a Canadian traceback program aimed at verifying Canada’s initial findings was conducted.

Under the terms of the restriction, Canada restricted seed imports and mandated that potatoes for consumption be treated with a sprout inhibitor and meet other requirements. Mop top causes discoloration in potatoes. It is not harmful to humans but makes potatoes inedible.

From the beginning of the Canadian restriction, Keeling has stressed that mop top is a North American, not a U.S.-only, issue, and that Canada must conduct its own tests. Following CFIA’s decision to do that, Keeling is more optimistic about a speedy and amicable end to the problem.

“There’s been good cooperation so far between APHIS and CFIA,” Keeling said. “I think we have a shot at getting this done before a shooting war starts.”

Keeling added that so far, the Canadian restrictions on U.S. potatoes have not had a negative economic impact on U.S. growers.