This article appears as the cover story in the January 2017 issue of Potato Grower.
You’ve got your russets, your reds, your fingerlings and babies and one-pounders, and even some fancy pink- and purple-fleshed ones. But for a consumer, in the end a potato is still just a potato, right?
Of course, those of us in the industry know that’s not true. Well, part of it is: a potato is indeed a potato and in many ways very similar to its tuberous brethren. However, though the family resemblance may be strong, the diversity among potatoes is just as great as in any human clan (in spite of all the clones). And while some members of the family may have attained greater worldly notoriety than others, those cousins toiling in obscurity ought not to be forgotten or abandoned.
That’s where the U.S. Potato Genebank comes in. Part of the National Plant Germplasm System (NPGS), the genebank has for six decades collected and maintained a massive collection of potato genetics. Prior to 1950, potato breeding stocks were brought in by U.S. breeders on an individual basis, with little collaboration among researchers. But with the formation of the NPGS, potato scientists lobbies for a centralized program to acquire, classify, preserve, evaluate and distribute potato germplasm. Several breeders from Wisconsin were particularly passionate about the movement, so the state was awarded the genebank and ensuing responsibilities. It was decided the genebank should be built in Sturgeon Bay on Wisconsin’s Door Peninsula, removed from the state’s major potato production areas so as to avoid the virus pressure dreaded by any producer of high-generation seed.
John Bamberg has served as the project leader in Sturgeon Bay since 1989, and he considers the genebank to be the U.S. potato industry’s ultimate hardware store. Listening to Bamberg, it becomes obvious that his analogy makes a lot of sense:
“To most effectively serve its customers, the store has to offer (acquire) the broadest possible array of tools,” he says. “Those tools have to be organized on the shelves (classified) so customers can easily find what they need. The store has to keep a sufficient inventory of stock on hand and in working order (preserve enough germplasm, free of disease, with good germination).
“The best-case scenario,” Bamberg continues, “is that the staff develops manuals describing the uses for the tools and become proficient in their use themselves, so they can give firsthand advice to customers (evaluation). Finally, the store needs to be able to effectively advertise what is available and efficiently deliver it to the customer (distribution of information, technology and germplasm). These concepts parallel the germplasm service of genetic tools we hope to provide.”
The genebank’s inventory comprises some 5,000 populations of botanical seed and over 1,000 tissue culture clones. Those numbers include both established (Russet Burbank, Norland, Atlantic) and little-known (Alaska Frostless, Montanosa, Zarewo) cultivars of Solanum tuberosum, as well as 107 varieties of wild relatives like Solanum candolleanum, Solanum boliviense and Solanum andreanum. Keeping all that genetic material has more purpose to it than just compiling a long list of fun names; the genebank is constantly working to isolate genes that can prove useful to the U.S. potato market.
“Potato has about 100 species—more wild relatives that are accessible to breeding than any other crop,” says Bamberg. “At least 70 percent of new cultivar releases [in the U.S.] have exotic germplasm in their pedigrees. For many traits, like disease, pest and stress resistances, exotic germplasm has much greater extremes than found in the cultivar breeding pool.
“But the exotic germplasm also has use as research tools. For example, stocks from the genebank made it possible to sequence the potato genome and develop Simplot’s Innate technology. But as our genetic knowledge and technology advances, introduction of undesirable traits like weediness should become less of a problem, making our raw germplasm increasingly valuable.”
Though Bamberg and his colleagues sit on the bottom rung of the ladder that gets potatoes on people’s plates—a step before breeding, even—they are not naïve about the needs of growers and consumers. Nutritional new and trends are at the forefront of their minds as they work to improve potatoes’ nutritional value and make them a more attractive choice for consumers.
“Our mantra is that we want to keep genes instead of genotypes,” says Bamberg. “We cannot afford to keep every genotype clonally, but we constantly remain intent on gathering and securing the maximum number of useful genes.”
Thanks to the work of the genebank, potatoes should be doing the family name proud for a long time to come.