University of Kentucky

SCN is important in Kentucky because:

  • SCN causes greater annual yield reductions to soybean grown in Kentucky than any other pest or disease.
  • SCN has become more difficult to manage in Kentucky due to the major source of resistance in soybean varieties (PI 88788 source of resistance) being less effective than it once was.
  • Observable symptoms caused by SCN are rarely seen, except when it comes to soybean yield.
  • SCN may interact with other soybean diseases, which can cause additional stress on soybean plants and reduce overall yield.

SCN Management Recommendations

There are multiple tactics for managing SCN:

  • Collect soil samples in the Fall of the year near harvest time and submit to a laboratory to know what number of SCN eggs are in your fields
  • Rotate soybean with non-host crops, such as corn, to help reduce SCN populations in your fields
  • Grow SCN-resistant varieties.  Switch soybean varieties every year that soybean is grown in a particular field. If available, use varieties that contain different sources of resistance to SCN every year that soybean is grown in a particular field (i.e. PI 88788, Peking, etc.).
  • In combination with SCN-resistant varieties, consider using a nematode-protectant seed treatment.

 

Soil testing tips:

 

  • When:  Anytime from mid-September through early May; however, fall is generally considered to be the best time.
  • How often: Once every 4 to 5 years
  • Where should soil test samples be sent? The UK SCN Lab is currently closed due to renovations.  Send samples to a lab in an adjacent state such as:

University of Missouri Plant Nematology Lab, SCN Diagnostics, 1721 East Campus Loop, University of Missouri, Columbia, MO 65211-5315
573-884-9118
Email SCN Diagnotics
SCN Diagnostics website

University of Illinois Plant Clinic, S-417 Turner Hall, 1102 S. Goodwin Ave., Urbana, IL 61801
217-333-0519
Email Plant Clinic
University of Illinois Plant Clinic website

 

 

 

Rotate resistant varieties:

  • Switch SCN resistant varieties every year that soybean is grown in a particular field.
  • SCN is able to adapt to specific resistant varieties over time.

Rotate sources of resistance:

  • SCN is able to adapt to different sources of resistance used in SCN-resistant varieties.
  • The most commonly used source of resistance comes from PI 88788.
  • If available, use varieties that utilize a different source of SCN resistance every year that soybean is grown in a particular field.

Rotate to non-host crops:

  • Rotating to non-host crops, such as corn, will help reduce SCN populations in a field over time.

 

Nematode-protectant seed treatments:

  • Consider using in combination with SCN-resistant varieties

 

University of Kentucky Experts

Carl Bradley

Carl Bradley

Extension Plant Pathologist

University of Kentucky

carl.bradley@uky.edu

270-365-7541 ext. 215