Nebraska Extension’s CropWatch recently provided a reminder to soybean farmers that even though fall is a busy time with harvest, it’s also a great time to sample for soybean cyst nematodes, especially while waiting in the field in the grain cart or truck as the combine fills.
Soybean cyst nematode (SCN) causes the most yield limiting disease of soybeans in North America. Research has shown that SCN can cause over 40% yield loss in soybeans, including 30% yield loss that can occur with no other visible symptoms, making it an invisible yield threat. SCN reduces yields but typically doesn’t display aboveground visible symptoms in the field during the growing season unless the SCN population is very high, then stunting and yellowing in soybeans may develop. By the time you see symptoms caused by SCN, population densities may be very high and very difficult to reduce, so it is recommended to regular monitor for them by collecting and submitting soil samples for SCN analyses. You can collect a good sample for SCN in any crop, any time of the year you can get a soil probe in the ground. Since SCN lives in the upper 8 inches of soil, collecting a sample is easy.
For details on how to sample, go to cropwatch.unl.edu. Samples will be mailed to the UNL Plant & Pest Diagnostic Clinic where SCN analyses of 2021 samples will be conducted at no charge for samples collected from Nebraska fields, courtesy of support from the Nebraska Soybean Board. Bags are usually available at your local extension office.