Last Thursday, Jeffrey Endelman stood in a windy field east of Rhinelander, Wis., and fished a diagram out of his fanny pack.
“I’m continuing my selections in Family No. 91, at the moment, as I round the corner,” he explained, referencing the diagram. “If I look at Family 91, I see who the mother was, I see who the father was, I see how many plants I have.”
Endelman started walking the rows between the potato plants, each a hybrid between different varieties.
“I can look at the parents and I can see this is a cross between a russet and a round white potato,” he said.
Every so often, he bent down, collected a few fully-grown potatoes, and placed a little flag into the ground beside them.
“Here’s a good one,” he said, selecting a group of tubers. “Good size potatoes. The shape is reasonable, the eye depth looks good, the plant is not green. It has completed its life cycle.”
These potatoes have passed a ruthless visual test administered by Endelman, a professor of horticulture at UW-Madison and the scientific lead on the school’s potato breeding program.
Not only do the potatoes look healthy, but they’re the shape consumers expect. They’re not lumpy or spherical.
“It’s quite hard for potatoes, actually, to produce a long, straight tuber [like consumers desire],” Endelman said.
With flags and diagram in hand, he was walking behind a potato bed lifter, a machine that digs potatoes from the ground and gently lays them on the surface.
Endelman was inspecting some of the 170 tillable acres at UW-Madison’s Rhinelander Agricultural Research Station.
The land has been in potato production since the early 1900s. In the 1940s, commercial owner Lelah Starks gave it to the school and its then-relatively new potato breeding program.
“When she passed away, she ended up deeding it to the university to continue on with the potato variety development,” said station superintendent Becky Eddy.
Over the decades, UW-Madison’s program has become one of the premier potato breeding programs in the country.
In the field, just a few of every hundred potatoes passes Endelman’s eye test. Those tubers result from potato plants that themselves are in select company.
Each year, breeding at the station creates 40,000 or 50,000 new potato lines which are grown in greenhouses. One quarter-size tuber is selected from each tiny potato plant.
This year’s little greenhouse tubers will be planted outside, grow, then have their potato offspring inspected by Endelman next year.
“Every year, the genetics is not changing. But the environment is changing. Each year, we learn something a little different about these environmental conditions. Maybe [the potato] has a certain liability that we didn’t see last year. It takes a couple of years of evaluating the same clone, as we say, to really, truly asses the commercial potential,” he said.
Keeping each variety disease-free and genetically pure is a top priority, said Eddy.
“Everything here is attention to detail, just with the sheer number of lines and making sure that they all stay intact as that variety,” she said.
To that end, sanitization is key. Workers change clothes when transitioning from the field to the greenhouse. At every greenhouse door, staff steps through a green sterilization liquid.
The station’s ultimate goal is to develop potato varieties that appeal to farmers.
“What we’re really trying to focus on over the next couple of years is to try to get resistances to certain diseases into our genetics,” Eddy said.
Developing commercially successful varieties brings back royalties to the program that can be used to fund further research.
But finding a winning new breed is an extreme challenge.
Jeffrey Endelman says about one of every 100,000 cross-bred potato varieties actually makes it to market.
“You definitely have to be prepared to face failure all the time,” he said. “That’s true for any breeding, but the potato has a particularly difficult genetic system, so the odds of success are lower.”
The eyes of potatoes selected by Endelman this year will be planted in another field next year, where they’ll spawn a new crop for harvest.
hen, the analysis and selection process revs up again.
If researchers are lucky, perhaps one of the 40,000 varieties created this year will make it to market.
If one does, it will be given a name, maybe a name reflecting its origin. Oneida Gold and Hodag are two of the varieties recently released by the station.
The UW program also has its sights set on its next Wisconsin find.
“We’re still holding on,” Eddy said. “We’re trying to find that ultimate red variety so we can call it Badger.”