This article appears in the September 2020 issue of Potato Grower.

If your only exposure to potatoes were grabbing a 5-pound bag from the produce aisle or ordering fries at McDonald’s, you probably wouldn’t think there was much of a difference between one humble potato farm and another.

Of course, as anyone likely to be reading this knows, every potato-growing operation is unique, and every grower has to take different steps to ensure the potatoes that end up in shopping carts, a Lay’s bag, or even another grower’s planter are of the high quality the customer expects. That process, of course, continues well after those potatoes are pulled out of the ground. Storage needs are nearly as diverse as those for planting, irrigating and fertilizing a crop.

“To use the old cliché, one size does not fit all,” says Kiran Shetty, technical development lead for potatoes at Syngenta. “Production itself is quite diverse. We have process grade potatoes, we have fresh-pack potatoes, sometimes they’re mixed. Many growers are storing chipping stock. Many have seed potatoes. That all has some bearing on how they’re stored; they’re just not the same.”

Since its initial release in 2012, Stadium, a product from Syngenta, has performed well in helping maintain potato quality in storage on varied operations across North America. Shetty recently sat down with Potato Grower to discuss the considerations growers should make when considering a product for their storage programs, and how Stadium holds up to those measuring sticks.

1. Performance

Stadium is a fungicide that specifically targets the pathogens that cause Fusarium dry rot and silver scurf via three active ingredients: fludioxonil, azoxystrobin and difenoconazole. The utilization of three actives prevents the pathogens from developing resistance, thus improving the long-term efficacy of Stadium.

“When these products are introduced into the industry, it is incumbent on the chemical manufacturers to make sure they last long enough, given the history of resistance development to active ingredients,” says Shetty. “So when you combine more than one, there’s less opportunity for the pathogen to develop resistance. In that regard, Stadium has been used very successfully in potatoes.”

2. Compatibility

Growers need to be aware of how a particular treatment will fit in with the characteristics of their individual operations. Variety, end user, growing conditions, and even the unique aspects of a particular storage play a part in determining which products to apply—and the manner in which they are applied—to potatoes in storage.

“When Stadium—or any other product—is applied, it should be compatible with other registered chemistries or practices that might be used in storage,” says Shetty. “We try to make sure that all these attributes are addressed properly so that we can position Stadium for proper use.”

3. Label Amendments

As with any product that sticks in the industry, some changes have been made to Stadium’s label over the years, most of which benefit growers. Early on, Stadium was not approved for use on seed potatoes—a precaution taken to prevent any aforementioned resistance. But Syngenta, in tandem with university and private researchers and growers across the country, has put in the work to test the product extensively on seed potatoes. The result is a confidence that Stadium is effective and beneficial when applied in seed storages.

4. Application

“Application requires a lot of attention,” says Shetty. “Every farm has some kind of variation in how they harvest, transport and store, and each has a reason for doing it that way. The question for us became, ‘How adaptable is Stadium to different application methods? Can it work with varied techniques?’”

To answer those questions, Shetty has worked with potato researchers at the University of Idaho, Michigan State University, the University of Wisconsin, North Dakota State University and the University of Maine to determine the best application rates and methods from region to region and farm to farm.

“The bottom line,” says Shetty, “is that Stadium has proven adaptable to all those conditions.”

5. MRLs & Export Requirements

Growers, packers, processors and chemical manufacturers need to constantly be aware of where their potatoes are headed, particularly if they are bound for foreign markets. Every country has its own rules and regulations about how potatoes and potato products have been handled prior to entry. Potatoes treated with Stadium in particular face multiple challenges, as each of its three active ingredients must get approval from every market.

The good news, Shetty says, is that over the last several years, significant progress has been made on getting those approvals in major export markets. Perhaps most notably, he says potato products treated with Stadium are likely (with a cautious emphasis on the word “likely”) to have all the necessary approvals for export to Japan.

“We’re always getting closer to full approval in major export markets,” Shetty says.