University of Illinois Urbana-Champaign Partner

SCN is an economically important pest because:

  • SCN is considered the number one yield robber of soybeans in Illinois.
  • SCN is found in every county in the state.
  • SCN is present in an estimated 70-80% of statewide agricultural fields.
  • Many Illinois SCN populations can reproduce on the most widely used source of resistance (PI 88788). This means that using soybeans with this source of resistance may not result in sufficient control of SCN populations. 

SCN Distribution

 

SCN Management Recommendations

There are multiple tactics for managing SCN:

  • Test soil for SCN numbers and HG types to assess the effectiveness of your SCN management program.  Testing fields every 3-5 years is a good way to stay on top of SCN populations and minimize economic impacts.    
  • Use an SCN resistant variety and if possible use a variety with a resistance source that will manage the HG types in your fields.  Even if a variety with PI 88788 is used, it will provide better control than a variety without SCN resistance. 
  • SCN resistance is complex, and different varieties with the same source of resistance often differ in their effectiveness to control SCN populations.  Rotate soybean varieties, especially if planting continuous soybeans.
  • Rotate to non-host crops (e.g. corn, sorghum) to help prevent a buildup of SCN.  More than one year away from soybean may be required to sufficiently reduce the SCN population to a non-damaging level.  
  • If resistance and rotation are not working as determined by soil sampling and yield, consider incorporating additional options.  Examples include the addition of nematode protectant seed treatments, cover crops, or the use of double crop soybean production systems. 

Soil testing tips:  

  • Where in the field? Low spots, areas of high soil pH, field entry points, randomly throughout the field.
  • When? At planting before soybeans or at harvest preceding a soybean rotation.
  • How often? Every 3-5 years if populations are low. Every year if populations appear to be increasing.
  • Where should soil test samples be sent?
    University of Illinois Plant Clinic
    1102 S. Goodwin
    S-417 Turner Hall
    Urbana, IL 61801

What to know about rotating different resistant varieties:

  • Most resistant soybean varieties carry the “PI 88788” source of resistance.
  • Many SCN populations in Illinois can overcome PI 88788 resistance.
  • Not all varieties of soybean with PI 88788 contain the same exact resistance genes. 
  • If you can only select PI 88788 varieties, consider changing lines within a company or changing companies.
  • Rotating to the less common “Peking” source of resistance may be beneficial.

 

 

What to know about rotating different sources of resistance:

  • Few sources of resistance are available in commercial varieties; consult with your seed dealer.

What to know about rotating to non-host crops:

  • Corn is an excellent rotation crop. SCN will not reproduce on corn.  Sorghum may be an option in some areas of the state.
  • Some cover crops may be hosts for SCN such as legumes. 
  • Rotating to a non-host will not eliminate SCN, but will prevent populations from increasing. 

Nematode-protectant seed treatments:

  • There are several nematode-protectant seed treatments available in Illinois.
  • The value of these treatments for SCN management are limited but potentially can help manage SCN when used in combination with other recommended SCN management practices. 
  • The benefit of these products likely depends on the level of SCN in your fields. 

University of Illinois Experts

Nathan Kleczewski | Plant Pathologist

University of Illinois Urbana-Champaign

217-333-3420    

Nathan Schroeder | Nematologist

University of Illinois Urbana-Champaign

217-244-6128

Suzanne Bissonnette | Assistant Dean

University of Illinois Urbana-Champaign

217-333-2478


Other SCN Management Resources