Soybean growers across North America are being urged to pay closer attention to soybean cyst nematode (SCN), as experts warn that the pest may be causing significant but unseen yield losses this season. Marking National Nematode Day, The SCN Coalition — together with Syngenta, Indigo, and BASF — highlighted the ongoing threat posed by SCN, which remains the continent’s most damaging soybean pathogen and accounts for an estimated $1.5 billion in annual losses.
Despite relatively favorable weather in many areas, researchers caution that SCN-related damage can be masked by timely rainfall. That means fields appearing healthy at harvest may still be suffering hidden yield penalties. Because symptoms are often subtle or nonexistent, soil testing remains the most reliable way to understand the scale of the problem, especially as the pest continues to build resistance to PI 88788 — the dominant resistance source in commercial soybean varieties.
Experts recommend sampling fields at the end of the soybean season, when SCN populations reach their highest levels. Uniform sampling is key, though additional samples may be needed in fields with variable terrain, high pH zones, sudden death syndrome symptoms, or unexpectedly low yields. Repeating tests at consistent intervals — generally every second or third soybean crop — allows farmers to track long-term SCN trends and evaluate whether management strategies are working.
Several states continue to offer free SCN testing programs, and growers are encouraged to contact Extension offices for details. Tools such as the SCN Profit Checker can also help farmers estimate yield-loss risk using local SCN counts, soil characteristics, and historic yield data.
While resistance packages based on Peking genetics and current seed treatments form an important foundation, researchers emphasize that more tools are on the way. One of the most notable is Nemasphere, BASF’s upcoming trait designed to impair nematode feeding using a novel Cry14 protein. Field trials suggest the trait may increase yields by an average of 8%, and BASF plans to release it stacked with Enlist E3 herbicide tolerance pending regulatory approval.
Syngenta’s forthcoming Victrato seed treatment is another anticipated option. Built on new SDHI chemistry (TYMIRIUM technology), it targets multiple life stages of key nematode species and provides early suppression of certain foliar diseases. Multi-year trials indicate that the product could deliver meaningful yield advantages once approved.
As SCN continues adapting to long-used resistance sources, agronomists are urging growers to practice careful stewardship. Rotating resistant varieties, diversifying resistance genes, and incorporating non-host crops are key steps to extending the life of current and future technologies. The overarching message: consistent testing and proactive rotation are critical to keeping SCN in check — and protecting soybean yield potential for the long term.
