Updated December 2, 2016:
Final Progress Report is downloaded in the File (optional) below

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Increasing awareness of Soybean Cyst Nematode in North Dakota: 2015.
PI: Sam Markell, Ph.D.
Co-PI’s Guiping Yan, Ph.D. and Ted Helms, Ph.D.

In 2015, The North Dakota Soybean Council funded an Extension and Research program designed to educate North Dakota soybean growers about the threat posed by Soybean Cyst Nematode (SCN). The core of the Extension program was a producer-based SCN sampling effort operated by the NDSU Extension Service.

Soybean Cyst Nematode (SCN) is the most important yield-limiting disease threat to soybean production in the United States. This parasitic worm lives and reproduces on soybean roots, severely stresses plants and spreads by anything that moves soil. In 2003, SCN was first identified in North Dakota and has been quietly spreading through the state.

Growers have tools to manage SCN (such as resistant varieties and good crop rotation strategies) but they are most effective if SCN is identified before the pathogen reaches epidemic levels in the soil. Unfortunately, symptoms of SCN are notoriously absent, making detection by visual inspection of fields difficult. Commonly, spots in a field may take a 15-30% yield loss before any above-ground symptoms appear and when they are visible, they are expressed as non-specific yellowing and stunting of plants. Consequently, soil sampling is the most effective way to detect SCN and it is the only way to determine egg levels in a field once you have it.

To educate North Dakota soybean growers about SCN and to encourage them to soil sample, the NDSC covered the cost of lab-fees of up to 2,000 pre-labeled SCN sample bags. The pre-labeled sample bags were distributed to every NDSU County Extension office, at three SCN-specific field days, other NDSU field days and by cooperators in the private industry. Once the bags were sent into the laboratory, egg counts were determined and the submitter received the results in the mail. Additionally, egg level and geospatial data (all other information was kept anonymous) were used to generate maps of SCN distribution in North Dakota. Some additional data from cooperators were also used in map creation.

By January 1st, 943 SCN sample bags were submitted from nearly everywhere soybeans are grown in the state. Over 25% of the submitted samples were positive, although some of them were ‘low level positives’ (gray boxes) and should be viewed with some caution. However, high egg levels were found in many counties. The highest egg levels recorded in 2015 were in the Southeastern part of the state, where SCN has been present the longest.

This program was designed to directly benefit soybean growers in North Dakota by giving them information about SCN and the encouragement (and opportunity) to sample for it. We thank all of the growers who allowed us to hold field days in their fields and the growers, county agents and cooperators who participated in the sampling program. In additional to the benefit of a free sample you have helped raise awareness in your region every time a positive sample show up on the map. Thank you!