Protect Yields from Soybean Cyst Nematode

Management Tips to Take Control

Aired: August 2013

The greatest contributor to soybean yield loss in North America, Soybean Cyst Nematode (SCN), is also one of the hardest to diagnose.  With every county in Illinois affected by the pest, proper management and prevention will help keep prevalence low and preserve the yield potential of resistant varieties.

Jason Bond, Ph.D., Southern Illinois University-Carbondale Plant, Soil and Ag Systems associate professor, provides background on SCN and explains what soybean farmers can do to prevent, detect and manage it.


Key Takeaways

  • Data collected over the past 10 years show SCN affects approximately 80 percent of Illinois soybean fields.
  • SCN cannot be completely eradicated once present in a field, but with proper management can be controlled.
  • The only way to detect SCN before it becomes a major problem is to sample fields with no symptoms, but where SCN is likely to establish first.  Soil samples should then be analyzed by a professional diagnostic laboratory.
  • Always use an SCN-resistant soybean variety; not all are created equal.
  • Other effective management strategies include:
    • Rotation with nonhost crops and resistant varieties
    • Maintaining adequate fertility
    • Controlling weeds, diseases and insects


  • Potential above-ground symptoms:
    • Elongated damage (stunting of plant growth, changes in leaf color, wilting, yield loss) in the direction of tillage
    • Most severe damage in the center of the affected area
    • Located near a field entrance, or in areas where soil from another field is deposited by wind or water
  • Below-ground symptoms:
    • Dwarfed or stunted roots and fewer nodules
    • Presence of cysts on the soybean roots, appearing as lemon-shaped structures–evolving from white to yellow to brown