Wednesday, December 27, 2017

10 Things to Know About Managing Soybean Cyst Nematode

Burrus Account Manager Ross Kleinsteiber & Jason Zimmer discuss SCN during an agronomic field visit.

1. Soybean cyst nematode (SCN) is the #1 threat to soybean production worldwide.

2. In cases of high SCN populations, SCN cysts may be visible on roots. Roots could also have poor nodulation and plants could be uneven, stunted, or have low numbers of pods or beans per pod.

3. SCN can be confused with other problems such as root rot, nutrient issues, pests, or compaction. SCN, like other pests, will be located within patches of a field and symptoms may be more noticeable in seasons lacking adequate moisture due to root injury.

4. Growers can test for SCN in the fall by submitting soil samples to university labs where they will sieve, process, and do SCN egg counts for a fee.

5. We have been depending on the PI 88788 source of resistance in 95% of the U.S. seed market share. Other sources of resistance come from Peking, PI 437654, or combinations.

SCN cysts were found on the roots of this soybean variety which consisted of the PI 88788 source of SCN resistance.
6. SCN resistance to PI 88788 was documented in 2007 and 2008, by Mitchum et al and Niblack et al, respectively. As SCN presence within soil samples are screened at the university level, the problem appears to be getting worse.

7. Each nematode has different genes and those not affected by plant resistance can pass along those genes to their offspring (200-500 eggs) by reproducing sexually, which only increases the number of SCN unaffected by PI 88788.

8. If you want to confirm PI 88788 resistance, there is a HG test that can be done by university labs. It is a 30-day greenhouse test which will determine a female index, the average number of SCN females produced on seven indicator lines relative to the number produced on a standard, susceptible soybean cultivar.

9. Another control of SCN consists of an integrated management approach that includes crop rotation to help reduce populations and if possible, but not likely, see if you can use another source of SCN resistance such as Peking. In addition, the Illinois Soybean Association is seeking grower partners for a study next year to validate the hypothesis that wheat straw (or grass cover crops) can suppress SCN populations. For more information, visit 

10. Though not a total cure-all, we strongly recommend ILeVO®, included in our PowerShield® SDS seed treatment, for the early season control of SCN in conjunction with SCN management strategies.

by: Stephanie Porter, Burrus Sales Agronomist