The three main stages of the SCN life cycle are the egg, juvenile, and adult female. SCN can complete its life cycle in four weeks under ideal conditions (soil temperatures at 75° F)
*All life stages not depicted at same size scale*
Key points to know
1. Stunting and yellowing can be above-ground symptoms of SCN
Recommended technique: Collect soil samples and have them tested for the presence of SCN.
When to sample
Fall is often the best time to sample as you plan for the next crop year. Sample as described below in the harvested field that is to be planted with soybeans next season.
Recommended technique: Collect soil samples and have the SCN population densities determined.
When to sample
You can take a soil sample to check on the progress of a SCN management plan at almost any time of the year. But if you want to monitor the effectiveness of your SCN management program over several years, you should sample at the same point in the management program each time (say after a year of resistant soybeans or nonhost crop).
Recommended technique: Collect soil samples and have them tested for the presence of SCN.
When to sample
Fall is often the best time to sample as you review harvest data. Take samples from the harvested soybean field, either in a zig-zag pattern or as part of a grid sample, as described below.
A good starting point is the Soybean Cyst Nematode Management Guide published by the SCN Coalition in 1999. There are many excellent SCN-related resources available on the web. Many are accessable through our links section, or are available as the following ISU Extension Nematology Publications.
Here at ISU, we have two management recommendation for SCN-infested fields. The recommendation given is based on the SCN egg population density (egg count) of the sample submitted.
Recommendation #1 - for fields with egg densities up to 5,000 eggs per 100 cc soil
We recommend that growers follow a six-year crop rotation scheme as illustrated below:
Here at ISU, we have two management recommendation for SCN-infested fields. The recommendation given is based on the SCN egg population density (egg count) of the sample submitted.
Recommendation #1 - for fields with egg densities up to 5,000 eggs per 100 cc soil
We recommend that growers follow a six-year crop rotation scheme as illustrated below:
It is impossible to provide such precise information about the potential for yield loss because the amount of damage caused by SCN is very dependent on numerous interrelated factors including:
