Research funded by the United Soybean Board and soy checkoff has made a breakthrough that could strengthen the soybean plant's resistance to soybean cyst nematode. This disease causes more than $1 billion worth of soy yield losses annually.
"SCN has been devastating soybeans ever since I've been involved in the industry," says Jim Schriver, chair of USB's production program and a farmer from Indiana. "This is a great use of biotechnology that can help farmers break through yield barriers so we can continue to increase production and meet demand."
Farmers have been planting soybeans containing a genetic structure called Rhg1, the top defense against SCN. But ways to further improve that resistance have eluded plant scientists.
In a study recently published in the journal Science, however, researchers reveal that Rhg1 is actually three genes located next to each other on the chromosome, that work together to make a plant more resistant to SCN. SCN-resistant varieties carry multiple copies of this multi-gene block.
This discovery allows researchers to quickly find soybean varieties that include these repeated three-gene blocks. It also allows researchers to work with those genes to develop new SCN-resistant varieties.
Andrew Bent, professor of plant pathology at the University of Wisconsin-Madison, said the finding "opens the gate for us to walk in" and take SCN resistance to the next level.
"It's been a goal of biologists for nearly 20 years to identify this Rhg1 gene," says Bent, who has been working on the project for about six years. "The United Soybean Board knew it was important work, and they were very supportive. The real value of the work will be seen in the next few years."
Bent collaborated on the study with several other researchers, including Matthew Hudson of the University of Illinois.