Adapted from article by Dr. Anne Dorrance, OSU Plant Pathology, C.O.R.N. 2020-36
The Soybean Cyst Nematode (SCN) is an invasive species has adapted quite well to Ohio conditions, and is unfortunately doing very well in some fields based on egg counts. We are wrapping up intensive sampling of Ohio Fields from the support of the soybean check-off through Ohio Soybean Council and United Soybean Board. To date, 566 samples were submitted from 34 counties. From these, 33.7% had populations of 200 eggs or more. There were 7.6% in the high range (>5,000 eggs per cup of soil), which are associated with significant yield losses.
More importantly, from these samples that had high numbers, we have completed the SCN Type test. This evaluates which resistance will be effective, PI 88788 or Peking. From the 56 SCN populations (each from a single field), only 7 populations were still controlled by PI 88788. The remaining populations could reproduce on the soybean roots of the PI 88788 source of resistance, albeit at levels of 30 to 60% of the susceptible.