While much of the 2025 season has been shaped by rainfall and resilient soybeans, the soybean cyst nematode (SCN) remains the number one yield-robbing pest across North America. With an estimated $1.5 billion in annual yield losses, it's a threat that often escapes visual detection but can devastate productivity silently.

This October 6, designated as National Nematode Day by the SCN Coalition in partnership with Syngenta, BASF, and Indigo, farmers are reminded that hidden SCN infestations could be undermining their profitability-even in otherwise healthy-looking fields. According to Dylan Mangel, Extension plant pathologist at the University of Nebraska, many growers may be misled this year due to higher-than-normal rainfall. "Some of those symptoms can be hidden, so something that's already hard to detect may be a little harder still."

The first line of defense is soil testing, particularly critical as resistance to the PI 88788 gene-the most widely used SCN-resistant source-continues to build. Testing fields post-harvest is the most accurate way to catch peak SCN populations. Uniform sampling, especially in areas with high pH, poor drainage, sudden death syndrome (SDS), or yield inconsistencies, can help farmers make informed management decisions. Industry experts recommend sampling every second or third soybean crop to track trends over time and determine if resistance or seed treatments are effective.

Farmers in states like Nebraska and Ohio may be eligible for free SCN soil testing, and tools like the SCN Profit Checker allow growers to estimate risk using egg counts, soil type, and expected yield.

New control technologies are also emerging. BASF's Nemasphere, a transgenic trait expressing the novel Cry14 protein, disrupts nematode feeding and has shown 8% yield increases across more than 200 field trials. It's being stacked with Enlist E3 herbicide tolerance, with market entry projected for 2028, pending regulatory approval. Meanwhile, Syngenta's Victrato seed treatment-based on TYMIRIUM™ SDHI technology-is undergoing EPA review. Trials between 2015 and 2022 reported an 84% yield advantage in fields treated with Victrato, which also offers early suppression of foliar diseases.

Still, technology alone won't solve SCN. Experts stress the importance of rotating resistant varieties, integrating non-host crops, and avoiding repeated use of the same resistance genes. "Switching it up will make that variety and those resistance sources stronger for longer," says Mangel. Without strategic rotation and stewardship, SCN will continue adapting-and winning.