Determine the type of SCN in your fields.

Right now, the growing of SCN-resistant varieties is the best method we have to keep yields raised while still growing a soybean crop. But since most resistant varieties we are planting are derived from one source of resistance, by nature, we are selecting a few nematodes out of a hundred that can reproduce on a resistant variety. After several years of growing resistant varieties, eventually a field can have a population that is resistant to a certain line of resistance. To identify this population change we have also implemented a brand new test titled the SCN Type test.

What is the SCN Type test and what does it tell you?

The SCN Type test is similar to the new HG Type test and race test, but is more streamlined for farmers because it only tests samples against lines of resistance available in commercial varieties. The way the test works is cysts from your field are analyzed on three different lines of resistance (lines of resistance, or source lines of resistance, are those parental lines used in breeding programs that contain the genes responsible for resistance against SCN). Eggs from those cysts are extracted, and equal numbers are used to infect plants with resistance, as well as plants that are susceptible. After we let these grow hydroponically for 30 days, theses plants will eventually grow cysts. We will then count the number of cysts, and determine from these numbers what the SCN Type of your field is.

What you will then know once you get the results is which type of resistant soybean variety or varieties will work best in your field, saving you years of variety trials and possible unnecessary yield losses that occur. Once you know your SCN Type, you can then choose varieties with the best yield history that have the appropriate source of resistance. Make sure to also address disease issues that field may have.

The test itself will take at least a month to perform because of the 30 day life cycle of SCN, and because this is a greenhouse assay. If egg numbers are not high enough in the sample provided, cysts will be extracted and used to infect susceptible lines to raise egg numbers enough so that the test can be completed. If this is the case, an additional month is needed to conduct the test.