Soybean cyst nematode update

Why care about SCN.

The soybean cyst nematode (SCN) is the top yield limiting pathogen of soybean, responsible for an estimated 6.57 million bushels lost in Minnesota in 2019 alone. On a per acre basis, SCN costs us on average $8.25 (Crop Protection Network, 2021).

Soybean root with small white arrows pointing to cysts of SCN. Cysts are female nematodes swollen with eggs.

The higher the SCN population density (eggs in a little bit less than 1/2 cup soil) in a field, the more of both these microscopic worms there are to hatch and infect roots and the threat to soybean yield potential. Multiple SCN generations means that some of those eggs produced within the 2021 growing season can hatch and infect roots.

We in northwest Minnesota have an additional risk factor that folks in much of the rest of the country do not have: alkaline soil pH. SCN population densities tend to rise faster, and be more resilient to drop -even when SCN is actively managed- in alkaline soils. It can be quite costly to not know what is going on below-ground when it comes to SCN as SCN can cause 30% yield loss without causing plants to exhibit above-ground symptoms. I personally know of several farmers in northwest Minnesota that wish they had known earlier of an infestation. 

Strategic Farming: Let's Talk Crops! program features leaders of SCN Coalition. 

Just last week, I hosted a panel discussion called, "SCN: A threat so tough, it warrants a coalition" featuring two of the leaders of the national SCN Coalition, a group of academic and industry members that are committed to managing soybean cyst nematode. One of the panelists was Dr. Greg Tylka, Iowa State University Extension nematologist and preeminent SCN researcher for the last 31 years (and counting). The other panelist was Dr. Sam Markell, Extension broadleaf plant pathologist at NDSU. Drs. Markell and Tylka answer questions submitted by audience members in this fun and entertaining video.

Free SCN soil sample analysis.

The fact that the little winter snow we got in northwest Minnesota retreated weeks ago likely means that folks have gotten many pre-plant tasks complete.  As we wait for the threat of hard frosts to pass and insurance dates to arrive, once you can get a soil probe into the ground there is a bit of time left for spring soil sampling for SCN.

If you grow soybeans in Clearwater, Kittson, Mahnomen, Marshall, Norman, Pennington, Polk, Red Lake or Roseau Counties and have an interest in soil sampling for SCN, we have grant funding to pay for the analysis of up to 140 samples. 

Those interested in participating in this program, please contact Angie at (218) 281-8692 or apeltier@umn.edu.  Sample bags and sampling instructions will be mailed on a first-come, first-served basis.