When you start crunching numbers on soybean cyst nematode (SCN) infestations, the yield losses and economic consequences cannot be overlooked. SCN is considered the No. 1 yield-robbing pathogen of soybeans, responsible for annual losses exceeding $1.5 billion.¹
Learning how to estimate the economic impact of SCN on soybean farming can help you implement proactive management tactics.
Soybean cyst nematode yield loss by the numbers
Soybean cyst nematode is often referred to as a “silent yield robber” because many growers reach the soybean cyst nematode economic threshold and suffer from damaging levels of SCN before even discovering an infestation. Though awareness is increasing, as recently as 2024, growers in the Northern, Western and Eastern Cornbelt still estimated only 14.4% of soybean acres were infested with damaging levels of SCN. However, soil tests showed that, in reality, 58% of sampled fields in the cornbelt contained damaging levels of SCN.²
Despite the discrepancy between awareness and reality, soybean cyst nematode yield loss accounts for 36% of all disease-related yield losses.³
And SCN is nothing new — it has been a costly problem in soybean production for decades. Between 1996 and 2021, the total soybean crop value lost to SCN has ranged from $600 million to $1.8 billion.⁴
SCN egg populations and their effect on final soybean yield
Understanding how soybean cyst nematode egg populations impact final yield can reveal exactly how SCN affects your bottom line. According to SCN-resistant trials conducted by Iowa State University, soybean varieties with the lowest end-of-season egg population densities were the highest yielding, whereas fields with increasing egg population densities produced lower yields.⁵
The worst part? Thanks to SCN’s high rate of reproduction, the egg population can skyrocket extremely quickly. The SCN Coalition gives this example: In a handful of soil containing 100 eggs, approximately half will be females capable of producing 250 additional eggs each. Even with a high mortality rate, three generations of SCN later, that adds up to 24,414 eggs in that same handful of soil.⁶
SCN resistance and new SCN management strategies for maximum profit
SCN has developed significant resistance after widespread and nearly exclusive use of the PI 88788 gene, and the efficacy of this trait is predicted to decline significantly as SCN adapts. Because of this decline, an increasing number of soybean growers began using the alternative Peking source of resistance. But Peking’s effectiveness is also declining due to intense selection pressure and SCN’s ability to adapt.
You can test your field’s resistance to the PI 88788 and Peking gene using an HG type test. An HG type test is a greenhouse test that determines how well your soybean cyst nematode population can reproduce on the sources of SCN resistance currently available in the soybean varieties you planted.
If PI 88788 and Peking are no longer effective against your SCN population, hope is on the horizon. Coming in 2028, Nemasphere™ is the first EPA-registered transgenic trait for soybean cyst nematode control. Nemasphere uniquely targets SCN from within the plant itself, complementing existing practices like resistant varieties and crop rotation to reduce nematode reproduction and protect yield potential.
You can learn more about how Nemasphere can help you fight against soybean cyst nematode by watching this video.
Experts are available to help you pick SCN management strategies for maximum profit. Reach out to your seed retailer, a nearby extension office agent, or a seed company professional like your regional BASF representative.
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Endnotes
- King, Loren. “Farmers Improve Soybean Cyst Nematode Control.” The SCN Coalition, 3 Mar. 2026, www.thescncoalition.com/news/2026/03/02/soybean-farmers-soybean-cyst-nematode-control-guides/. Accessed 30 Mar. 2026.
- Currie, Caroline. “Farmer perspectives on SCN”. The New Standard for Nematode Management, 22 May 2024, BASF Agricultural Solutions, Research Triangle Park, NC. Presentation.
- Arjoune, Youness, et al. “Soybean Cyst Nematode Detection and Management: a Review.” PubMed Central (PMC), 7 Sept. 2022, www.ncbi.nlm.nih.gov/pmc/articles/PMC9450454/. Accessed 8 Sept. 2024.
- “70 Years of Progress Fighting Soybean Cyst Nematode.” Soybean Research and Information Network - SRIN, Mar. 2023, soybeanresearchinfo.com/wp-content/uploads/2023/03/70-year-overview-SCN-Brochure-SRIN.pdf. Accessed 8 Sept. 2024.
- Tylka, Greg. “Substantial Yield Suppression from SCN Seen in Soybean Varieties with Resistance from PI 88788 in 2021.” Integrated Crop Management, 11 Nov. 2021, crops.extension.iastate.edu/cropnews/2021/11/substantial-yield-suppression-scn-seen-soybean-varieties-resistance-pi-88788-2021. Accessed 8 Sept. 2024.
- “Frequently Asked Questions About SCN and The SCN Coalition.” The SCN Coalition, 3 May 2023, www.thescncoalition.com/resources/faq/. Accessed 8 Sept. 2024.
