Ohio State University

SCN is important in Ohio because: 

  • SCN contributes to soybean yield loss in Ohio every year.
  • Low yielding fields may have high SCN numbers with no above ground plant symptoms.
  • SCN infestations now occur statewide and can be detected in most fields in the state.
  • Some fields with high populations have adapted to the most common source of resistance (PI88788).
  • SCN distribution – Ohio.
  • SCN distribution – Nationwide.

SCN Management Recommendations

There are multiple tactics for managing SCN:

  • Identify fields with SCN + monitor populations.
  • Rotate crops.
  • Use resistant varieties wisely.
  • Use best cultural practices.
  • Manage other diseases (SDS, BSR).
  • Prevent introduction.

Soil testing tips:

  • Where in the field?
    • Low yielding areas (use GPS from yield maps)
    • Pockets where soybeans mature early
    • Areas with the presence of sudden death syndrome
    • Places subject to flooding
    • Entrances and borders of fields
    • Anywhere pH of soil is alkaline (pH higher than 7)
  • When?
    • The optimal window of time in which to monitor SCN population density is from one week before harvest until the ground freezes.
    • However, if the purpose of sampling is diagnostic, to identify the presence of SCN in fields with no previous record of it or to conduct a survey to determine its distribution in a region, then sampling for SCN at any time is suitable.
  • How often? Once every year, usually between harvest and freezing.

Where should soil test samples be sent?

C. Wayne Ellett Plant & Pest Diagnostic Clinic
Ohio State University
8995 E. Main St. Bldg. 23
Reynoldsburg, OH 43068-3399

Spectrum Analytic, Inc.
1087 Jamison Rd. NW
Washington Court House, OH 43160

Brookside Laboratories, Inc.
200 White Mountain Dr.
New Bremen, OH 45869

Sample Submission

 

Rotate different resistant varieties:

  • Use resistant varieties in rotation with non-host crops.
  • Do not plant resistant varieties in fields with very high numbers of SCN (10,000 eggs or greater).

Rotate different sources of resistance:

  • Do not use the same variety derived from the same source of resistance two years in a row. Doing so could result in a selection of SCN populations with the ability to reproduce on that source. It is best to switch up the genetics to other high yielding varieties as much as possible.
  • Ohio now has sizable populations of SCN that can reproduce on PI 88788. Rotate to varieties that use Peking as a source of resistance to prevent SCN reproduction.

What to know about rotating to non-host crops:

  • Rotating with non-host crops like corn, small grains, and alfalfa is the most effective method of controlling SCN.
  • Where SCN populations are high, it may take three years or more of non-host crops between soybean crops to reduce SCN populations significantly.
  • SCN can increase 10 to 30 fold per year on susceptible soybeans.
  • SCN can decrease up to 50% in one year of non-host rotation. Rotate, rotate, rotate!

Other SCN Hosts

Nematode-protectant seed treatments:

  • We do not recommend any seed treatments at this time to help with SCN.
  • More studies are in progress on both short term and long term effects on populations.

Ohio State University Experts

Horacio Lopez-Nicora

Horacio Lopez-Nicora

Plant Pathologist and Nematologist

Ohio State University

lopez-nicora.1@osu.edu

614-688-0528