Economic Impacts of Soybean Cyst Nematodes When Prices Are High

by | Mar 30, 2022 | Indiana Agriculture News, News Feed

SCN females on roots. Photo: The SCN Coalition

Higher input costs coupled with strong prices might sway farmers to plant more soybeans this year. Doing so comes with a risk: soybean cyst nematodes.

Greg Tylka, nematologist with Iowa State University, is hearing more rumblings about planting soybeans-on-soybeans in 2022. But without a soil test, it could do more harm than good.

“Beans-on-beans is a terrible idea if you have soybean cyst nematodes,” says Tylka. “My farmers rarely have sampled their fields, so they don’t know which fields have it and which fields don’t. They also don’t know which fields have high numbers vs. really low numbers. If they knew that information, then they could put what corn they’re going to grow with those expensive inputs on their worst [SCN] fields.”

The SCN Coalition has been urging farmers to “Take the test. Beat the pest.” The number one cause of yield loss for soybeans are SCN. With favorable futures prices, Tylka says farmers need to take steps for proactive management.

“There isn’t a farmer I know who has SCN that isn’t leaving money on the table, money in the field,” he says. “It’s because of the commonly available source of resistance called PI88788. It’s like only having glyphosate as your herbicide choice for 25 years. We’re on the same path with nematode resistance. 5 percent of the varieties have a different source of resistance called Peking—it’s like using a different herbicide.”

In his research, Tylka has witnessed a 22 bushel per acre difference between Peking resistance vs. PI88788.

“Back when beans were $9 a bushel, that was $200 an acre [lost],” says Tylka. “Imagine with $17 beans. Farmers are leaving money in the field by not knowing they have SCN. Once they know they’ve got it, they can start actively managing it.”

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