Breeders have identified soybean varieties with genetic resistance to the nematodes and have used them to create new resistant varieties. Resistant varieties yield more than susceptible ones when soybean cyst nematode (SCN) is in the soil, but until now, it wasn't clear whether that yield advantage held up at low SCN infestation rates.
"In the last decade, the University of Illinois has collected data on agronomic performance, including yield, but also data on the resistance of the lines as well as on SCN pressure in the field. We've built up a massive dataset from these tests," says University of Illinois soybean breeder Brian Diers.
By looking at 11 years of data from 408 sites around the Midwest, the researchers found that there was a yield advantage for SCN resistance even at low infestation levels--as low as 20 eggs per 100 cubic centimeters of soil. In environments with no SCN infestation, the team saw evidence of yield drag, where resistant varieties yielded slightly less than susceptible ones.
"But most fields in the Midwest do have at least some infestation," Diers says. "So, in most cases, there's little justification in planting susceptible varieties to avoid that potential yield drag." | READ MORE
February 27, 2017 By University of Illinois