43 years of spuds: Potato test facility has been at the forefront of new breeds for more than four decades

Potato breeders from all over the country count on the Agricultural Research Service potato research facility in East Grand Forks, Minn., to help them decide which new potato breeds are worthy of an industry name like russet Norkotah or russet Burbank.

Site manager Marty Glynn, who started at the site in 1971 as a researcher for North Dakota State University, has been in potato research long enough to have seen many of these varieties come into being.

The East Grand Forks research site was built in 1965 and always has been the premier potato research site in the U.S. It is a cooperative between the Northern Plains Potato Growers Association, the University of Minnesota, North Dakota State University in Fargo and USDA's Agricultural Research Service.

The building and most of the equipment belong to the ARS.

"Minnesota has two Ph.D.s up here and (breeding and genetic researcher) Jeff Miller, but we have two biochemists-microbiologists here. NDSU has one technician, and then their extension agent works out of here. The federal government has myself and five technicians," Glynn says. "One of the things we do is evaluate the new clones. ARS evaluates clones for, I think, 13 breeding programs in the United States."

Proving ground

Most are from other agricultural programs at universities.

"There's some USDA breeders like in Aberdeen, Idaho, and Beltsville, Md. Most of them are from land grant colleges like Wisconsin, Michigan, Colorado, Oregon, New York, Texas and Minnesota. They're from all over," he says.

The breeders send in their best clones each spring, then Glynn and his staff plant them in the same plot and later harvest them with the same equipment.

"They put them through all kinds of (testing to determine) what the yields is, what their susceptibility to disease is," Glynn says.

The sending programs evaluate their clones for field production and yield for a number of years before they ship them off to Glynn.

"And once they get to us, they're probably in our program for at least five to six years to make sure that they prove up, that they store well and that they will process," he says.

One of the things that makes the East Grand Forks ARS facility unique is its laboratories and production lines.

"We have so many controlled environment rooms," he says. "We have a research, microbiology and microchemistry lab, and we also have the three lines so we can make french fries, instant potatoes and chips."

Other research sites, like one in Idaho may have a French fry line, but not a chip line or instant potato line, and they don't have the kind of lab that ARS has in East Grand Forks.

"A lot of them have mini-fryers, like you see at McDonald's, and that's how they judge them, but it's not the same as running bulk like we do. You couldn't take a 10-pound sample to Simplot and find it on the other end," Glynn says.

All of the ARS equipment is one-twentieth scale of what industry uses and the same type as what you would find in an industry line such as Simplot's in Grand Forks, N.D.

"The whole industry is hooked to what the plant breeders do," he says. "We measure everything with a reflectometer -- it hits it with light, and the whiter it is, the light bounces back -- so if you have those dark chips in there, it's going to absorb the light. Industry wants everything as white as a sheet of paper."

When first started at the East Grand Forks site, a reflective reading of 55 was good enough for a chip, he says.

"That was the quality of potatoes we had then. Now they probably wouldn't accept them if they were below 65. That's due to the plant breeders and plant geneticists," Glynn says.

A potato clone is made by cross-pollinating one plant, typically an industry standard like a russet Burbank, with an experimental in the greenhouse.

"We call them clones, but it's not like cloning where they're injecting RNA or any of that," Glynn says. "It's just a terminology in the industry because it's a clone of these two plants."

Each clone is given a number, which will be its identifying label through all of its testing. Given the amount of samples they test, there simply is no better way to keep track.

"I bet they cross maybe a 100,000 to 150,000 plants a year," he says. "What we're really striving for in the whole industry is to find a potato that will process out of 38 or 40 degrees (storage), because right now, chips are held at 45 to 48 degrees."

Two or three degrees in a potato makes a world of difference. The cooler you can safely store it, the longer you can keep it. But it still must retain its freshness so that it processes well into chips or fries.

"Some varieties store at 48 degrees, but if you take them down to 45, they won't process," Glynn says.

Brown chips

You've probably seen brown potato chips before. Contrary to what many think, though, they are not burned, Glynn says.

"In a potato, there's a compound called sucrose. It's what you put in your coffee or on your cereal. That's made up of two simple sugars, and what happens is, when the potato hits any stress, field stress or whatever and it shows up in storage cold temperatures, there is an enzyme that breaks that loose so that you have two small sugars."

When those sugars hit the hot oil in a fryer, they turn brown.

"So the more of these reducing sugars you have, the browner your chip's going to be. So that's what all the plant breeders are striving for -- what they can process out of 38 to 40 degrees storage."

This also cuts down disease in the bins and reduces the need to apply sprout inhibitor.

"It simplifies a lot of tendencies," he says.

The site's YSI 2700 spectrometer measures sucrose, through an electrode inserted into ground potato flesh. It has 21 walk-in storage rooms at various temperatures to test temperature viability.

"We measure everything according to industry standards," he says.

The site also has a steam peeler that can peel 100 pounds of potatoes in 30 seconds. All the equipment is state of the art and most of it is brand new.

"We run some studies out nine months, others go 12 months" Glynn says. "Whatever criteria the plant breeder at that university wants, then we do that for them."

The results are sent back to the breeder. Some of it is published in the Valley Potato Grower magazine. Either way, Glynn's outfit is making no judgments on the breeds.

"We don't really rate them," he says. "We just give them crude numbers."

These crude numbers then are used to compare with other varieties, good and bad, to assign their potential value in the various markets or in subsequent breeding lines. The ones selected for production lose their numbered identifiers.

"After they've been through the whole process, through the plant breeder and through here, then they get named," Glynn says.