MADISON — When Jeff Endelman arrived on the UW-Madison campus in 2013 to take over the university’s potato research program, he had a long history to build on.
The potato research program began at UW-Madison in 1936 and over the years has produced some of the most widely grown potato varieties in the country.
“It was comforting to know I didn’t have to start from scratch,” Endelman said of the research program.
Many people might know that Wisconsin has a potato research program because of the size of the state’s potato industry, but not many know how the program works, Endelman said.
Seeds that go into research potatoes are grown at a research station in Rhinelan-der, he said. The research station is intentionally separated from the state’s primary potato-growing region, the Central Sands, to prevent the spread of diseases that are sometimes prevalent in the research process.
Cross-pollinated potatoes look like small green tomatoes, Endelman said, and each fruit contains several hundred seeds.
“Each seed is genetically unique with the potential to become a new variety, but very few have what it takes to become ... the top spud,” Endelman said during a presentation at the Wisconsin Crop Improvement Association annual meeting.
Because potatoes are a vegetable but also an agronomic crop, they have an interesting mix of requirements, Endelman said. Growers have to select varieties for appearance, such as size, shape, color, eye depth and skin finish; productivity, which includes yield, tuber set, maturity, disease resistance and dormancy; and culinary traits, such as dry matter, texture, flavor and processing quality.
About 50,000 seeds are planted into 4-inch greenhouse pots every year at the Rhinelander Research Station, and the tubers produced in those pots then go into the field.
“We end up with 50,000 piles of potatoes, and it’s a beauty contest at that point,” he said.
Between 1 and 5 percent of potatoes in first-year trials make it to year two, and after that they are shipped to Hancock for years three and four of the trials.
“In Hancock they take an X-ray of every potato tuber, and the length, width and height of every harvested tuber is recorded,” Endelman said.
In years five and six, the trial potatoes are shared with partners in other public breeding programs, and after that, field testing begins in the commercial market.
“It takes about 12 to 15 years from the time of the cross until a potato can be commercialized,” he said.
Throughout potato-breeding history, researchers used an eye test to select the best varieties, but now they can also use genetic markers to screen for resistance to key diseases.
Once a new variety is selected, it is protected with a plant variety protection certificate by the Wisconsin Alumni Research Foundation, or WARF. The variety can then be sublicensed to seed growers across the U.S.
Potato varieties can last a long time, Endelman said, with an example being the Russet Burbank potato that was released by researcher Luther Burbank in 1876. The potato is still widely grown in many parts of the country.
The first genetically modified potato was produced in the late 1990s by Monsanto, with the intent to resist the Colorado potato beetle. But the market eventually collapsed when there was consumer resistance to the product.
Another genetically modified potato was introduced in 2014 by the J.R. Simplot Co. in Idaho, but it is not yet known how widely accepted the potato will be, Endelman said.
He said Simplot hopes the way the potato was engineered will help calm consumer fears about it being a genetically modified food. The company calls its product the Innate potato because it does not contain genes from other species like bacteria, as many biotech crops do.
Instead, it contains fragments of potato DNA to silence a potential harmful chemical called acrylamide, which is suspected of causing cancer in people. Endelman said acceptance could be better this time around because the potato promises potential health benefits.
“If it becomes successful, I’m sure other genetically modified varieties will follow,” he said. “It was an incredible tool for controlling the Colorado potato beetle (in the ’90s). I think we will see it again one day.”
Wisconsin farmers grow about 60,000 acres of potatoes with a farm-gate value of $250 million. The state ranks third in U.S. production, behind Idaho and Washington.
About half of the potatoes grown in the state go into the fresh market, while the other half are processed.