South Dakota State University

SCN is important in South Dakota because: 

  • It has been confirmed in 30 main soybean producing counties.
  • High prevalence – 33% of the samples.
  • Can cause yield loss without obvious above-ground symptoms.
  • SCN populations can build up in the soil in a short time and once found, SCN cannot be eradicated from the field.
  • SCN distribution.

 

SCN Management Recommendations

There are multiple tactics for managing SCN:

  • Plant resistant varieties.
  • Practice crop rotation.
  • Rotate resistant cultivars.
  • Control annual winter weeds proactively.
  • Use nematicide seed treatments if high SCN populations are found in your field.

Soil testing tips:

  • Where in the field? Low yielding areas, low spots/water-logged areas, field entrance, along with the fence line
  • When? Any time provided the soil is not too wet or frozen
  • How often? Every two soybean growing seasons
  • Where should soil test samples be sent?
    • Nematode Testing Service: SDSU Plant Diagnostic Clinic
      SPSB 153, Box 2108
      Brookings, SD 57007-1090
    • (605 )688-5545 or (605) 688-4521

What to know about rotating different resistant varieties:

  • Rotate cultivars with PI 88788 as a source of resistance genes with those of Peking and other sources.
  • Rotate within PI 88788 cultivars.

What to know about rotating to non-host crops:

  • Rotation with non-host crops such small grains and corn help to keep SCN populations low.
  • Longer rotations (>2 years) away from soybeans are more effective.

Nematode-protectant seed treatments:

  • Nematicide seed treatments do help protecting soybeans from early nematode infection.
  • A higher return on investment is likely when SCN population density in the field is high >6000 eggs /100 cc of soil.

South Dakota State University Experts

Madalyn Shires

Madalyn Shires

Extension Plant Pathologist

South Dakota State University

Madalyn.Shires@sdstate.edu

605-651-5631