Potato parasite damage in Idaho, Quebec has Maine growers wary

PRESQUE ISLE – A parasite called nematode that is found in soils nearly everywhere can become a pest and a concern in areas where food is grown. In potato growing areas of Quebec and southeastern Idaho, growers have been hit, some hard.

It has not yet become a concern in Maine, industry officials said Wednesday, and the industry is against a plan to conduct soil tests nationally on potato growing acreage.

Golden nematode and potato cyst nematode are not a health concern – they have no effect on human consumption. However, they affect yields by attacking potato vines and the size and number of tubers on plants.

Affected acreage in Quebec and Idaho have been taken out of production, and the land involved may never be used to grow potatoes again.

In Quebec, the infestation involves 13,000 acres owned by 13 growers. In Idaho, the acreage is much smaller and affects one grower. Idaho has tested 50,000 other acres and has not come across other problems.

Potatoes grown on the infected land can be sold, but not as seed. The potatoes must be cleaned of any soil and packed in a plant in the affected area.

A history of the area and equipment used there has been done to find the source of the infestation. There is reportedly a $6 million fund for the survey.

“Most likely the growers involved will be out of business,” Don Flannery, executive director of the Maine Potato Board, said at an MPB meeting Wednesday. “Their land is worth zero.

“It’s a very serious issue,” he added. “We don’t want to become part of a national survey because of the consequences.”

The Animal Plant and Health Inspection Service of the U.S. Department of Agriculture has proposed the national survey. The proposal is to test 100 percent of potato fields growing seed potatoes and 10 percent of fields growing commercial potatoes.

Flannery said if a national survey is to be done, it should be done in both countries simultaneously.

Flannery hoped that growers in Maine wouldn’t furnish soil samples for Nematode testing if asked. He said they should refuse.

“It would be different if the issue involved human health issues,” Flannery said. “It has no effect on human health.

“It affects the growth of the plant,” he said. “All soils have nematodes, but some kinds have never been detected, and we don’t want these two types here.”

Nematodes are transferred from area to area by soil. It can be done through machinery used on infected land and brought somewhere else. That’s also why potatoes grown in infected soils must be washed diligently before being sold for processing or table stock.

Golden nematode had never been found in Quebec. Flannery said it has been found before in New York and in Newfoundland and British Columbia in Canada.

When the nematode is found in an area, the area is quarantined.

Flannery believes growers need assurance, or insurance, before widespread testing is done. If infestation is found on acreage it has dire consequences for the owner of the land. The land can never be used again for growing potatoes.

He believes growers need to be given compensation if land is quarantined from ever being used again.

Flannery said some things can be done to control nematodes. There are some varieties that are resistant to control efforts.

He explained that infestations usually occur in areas where there is little or no crop rotation. There is also a fumigation system that is effective to some degree, but it is very expensive, and even then it takes land out of potato growing rotation for a long time.

In Maine, the potato industry supports 6,100 jobs.