Maine potato farmers have wrapped up planting and are hoping for a good year.

“It’s been an odd spring. But we have had a great start and are ahead on the heat,” said Seth Bradstreet, a former agriculture commissioner who runs a vegetable farm and roadside stand in Newport and is a member of the Maine Potato Board.

The last year also was kind of odd and troubling for the Maine Potato Board and seed potato farmers, who spent many hours at work confronting a new potato pathogen in the region — Dickeya, a bacteria that causes the rotting disease blackleg.

“I was so busy with Dickeya,” Tim Hobbs, the board’s director of grower relations, said.

Last summer, an outbreak of blackleg struck customers of Maine seed potato farmers in other states and was in part traced back to Dickeya, a bacteria that seems to stay mostly dormant in Maine, only to fuel blackleg when the seed potatoes are planted in warmer climates.

Since then, the quasi-governmental potato board mounted a response to the outbreak, spurring new quality control and testing measures in the state’s seed potato certification program.

About 20 percent of Maine potatoes are sold as seed potatoes to other farmers growing spuds, while about 12 percent are sold in grocery stores and more than two-thirds go to chip and french fry processors. Most of all those potatoes originate from the Maine Potato Board’s Porter Seed Farm in Masardis, which supplies farmers with early generations of potatoes that are used as “seed” potatoes, in a multi-year cloning process.

Dickeya put Maine in the spotlight of the North American potato industry, with stories of major crop losses among some farmers in Maryland and Pennsylvania who buy Maine seed potatoes.

“Last year, it was all us, and we were the first ones to identify it,” Hobbs said. “It’s now becoming clear to the rest of the country that it’s a nationwide issue.”

The Maine Potato Board offered to cover the costs of Dickeya testing on dormant potatoes for Maine seed growers. Of 347 samples submitted, 15 percent tested positive for the presence of Dickeya.

The Maine Potato Board is finishing renovations on a laboratory that will be one of the first in the country that can accurately diagnose Dickeya, a bacteria that’s long caused crop losses in Europe. By the fall of 2017, the Maine Department of Agriculture, Conservation and Forestry, which oversees the seed potato certification program, is moving to all-laboratory testing for Dickeya and other pathogens measured in the program.

The amount of Maine land devoted to potatoes is down by about 3 percent this year to an estimated 48,500 acres, according to Hobbs. That’s continuing a long-term decline in potato acreage — down from about 58,000 acres 10 years ago — as farmers diversify their crops or age out of the business.

At the same time, there are a number of other crops with opportunities for potato farmers, including grains, which are often grown in rotation with potatoes.

The rise of the craft beer industry and increasing demand for a range of food-grade grains has spurred new ventures from traditional potato farms, including the Maine Malt House in Mapleton, led by the youngest generation of the Buck Farms family, and Benedicta Grains, an organic farm in southern Aroostook County growing a range of grains and legumes.

“So far it looks like a good crop,” said Jake Dyer, who co-owns Benedicta Grains with his wife and father-in-law.

Dyer also is working for the Maine Potato Board helping to develop alternative crops for potato growers. The University of Maine’s Aroostook Research Farm is hosting a public field day Aug. 22 to share some of that work, including field trials of chickpeas and malting barley.