By Greg Tylka
Growing resistant soybean varieties is key to profitable soybean production in fields infested with the soybean cyst nematode (SCN). Available SCN-resistant varieties change from year to year. To help Iowa farmers and those who advise them battle SCN, Iowa State University annually compiles a list of SCN-resistant soybean varieties for each upcoming season. This effort is supported by soybean checkoff funds from the Iowa Soybean Association, and the information is available in ISU Extension and Outreach publication CROP1649, “Soybean Cyst Nematode-resistant Soybean Varieties for Iowa.”
The publication was recently updated and is available from the ISU Extension Store.
Hundreds of choices, two sources of genetic resistance
There are 796 SCN-resistant varieties across maturity groups 0, 1, 2, and 3 listed in the publication. The varieties are from 30 different seed brands sold by 22 different companies.
All but eight varieties in the list possess resistance from the breeding lines PI 88788 or Peking. The list also contains information on two varieties possessing resistance from both PI 88788 and Peking and six blends, or physical mixtures, of varieties with PI 88788 and Peking resistance.
In addition to company and variety name and source of resistance for each variety, other details provided in the publication include relative maturity, herbicide resistance or tolerance (if any), and iron deficiency chlorosis (IDC) tolerance score. SCN is frequently present in alkaline soils, where IDC also occurs, making IDC tolerance an important defensive trait for SCN-resistant soybean varieties grown in such soils.
Source : iastate.edu