Soybean Cyst Nematodes: Managing the Billion-dollar Pest

Soybean cyst nematode
Soybean Cyst Nematodes are one of the most feared – and costly – threats in American agriculture.

Nematodes are the most abundant group of invertebrates on the face of the earth. Most are beneficial, but some, like the soybean cyst nematode (SCN), are not.

Responsible for yield losses of more than 30 percent in some soybean fields, SCN racks up about $1.5 billion in crop damage each year in the U.S., even outpacing the damage done by soybean aphids. And because SCN lives in the soil, plant damage often goes undetected until it’s severe.

The good news: There are effective methods for nematode management.

Soybean cyst nematodes (SCN) account for $1.5 billion in crop damage each year in the U.S. alone.

Close up of healthy soybeanDanger Signs of Nematode Infestation

By the time nematode infestations become severe, soybean plants appear generally stunted with yellowing leaves. Unfortunately, these symptoms can fit a lot of pest and nutrient problems, so growers should sample their soil for a proper diagnosis.

For visual inspection, growers should carefully dig up a plant and gently dip its roots in a bucket of water to remove the soil. Female nematodes that develop into cysts on soybean roots can be seen without magnification.

Analysis at a commercial or university soil lab provides more accurate diagnosis and assessment of population levels. Nematologists at the University of Minnesota recommend collecting 10 to 20 one-inch diameter by 6-to-8-inch cores from each of several localized "most likely" sites in the field. In-row sampling is preferable to between rows.

Taking Action Against Soybean Cyst Nematodes

There are several management strategies available for dealing with soybean cyst nematodes:

  • Consider planting an SCN-resistant soybean variety. Credenz® soybeans offer a robust portfolio of many resistant varieties to help growers manage tough and variable field conditions. Get recommendations for your area from your local Bayer sales representative.
  • Use a seed treatment. Bayer recommends ILeVO® seed treatment – the only product that offers effective protection against Sudden Death Syndrome (SDS) and broad-spectrum protection from nematodes, including SCN – two leading yield-robbers – in the seed zone throughout the critical growing period.
  • Put a rotation plan in place. Planting a non-host crop, such as corn, wheat or sunflowers, can help reduce SCN populations in your field. Your local Bayer representative can advise you on the rotation crops and number of growing seasons needed for your climatic area.

Works Cited

  • Chen, S., D.H. MacDonald, J.E. Kurle, and D.A. Reynolds The Soybean Cyst Nematode. Publication. University of Minnesota Extension Service. Web. 16 June 2011.
  • Jardine, Douglas J., and Timothy C. Todd. "Soybean Cyst Nematode." Soybean Cyst Nematode. Kansas State University Agricultural Experiment Station and Cooperative Extension Service. Web. 16 June 2011.
  • Poinar, George O The Evolutionary History of Nematodes: as Revealed in Stone, Amber and Mummies. Leiden: Brill, 2011. Print.
  • "SOY001 - Management of Soybean Cyst Nematode." North Carolina Cooperative Extension: Home. Web. 16 June 2011.
  • "Soybean Cyst Nematode." ISU Plant Pathology and Microbiology. Iowa State University Extension Service. Web. 16 June 2011.
Copyright © Bayer CropScience