By Shannon Beck
Soybean cyst nematodes (SCN) cost American farmers an estimated $2 billion in yield losses each year. Since the pest’s discovery in 1954, plant scientists have worked to combat its destructive impact. Now, researchers at the University of Missouri are on the verge of a breakthrough in SCN resistance technology.
“We are at the point now where we have a gene identified that we believe contains a new resistance to SCN, and, hopefully, this will lead to a new breakthrough,” said Sushil Chhapekar, post-doctoral fellow in the College of Agriculture, Food and Natural Resources’ Division of Plant Science and Technology.
Chhapekar is part of a new generation of plant scientists at Mizzou working to protect U.S. soybean crops. Under the mentorship of Henry Nguyen, professor of plant science and technology, he continues the university’s long legacy of soybean cyst nematode research.
“ The University of Missouri boasts a remarkable legacy in soybean genetics and breeding that dates back to the 1980s.,” Nguyen said. “Dr. Sam Anand evaluated more than 9,000 exotic soybean germplasm for SCN resistance Many of those lines, along with hundreds more developed by Mizzou’s soybean program in the last 15 years, have contributed to the SCN resistance currently available.
According to Nguyen and Chhapekar, 95% of soybeans currently on the market with resistance are derived from limited genetic resources, and that means that the nematodes are adapting and steadily becoming resistant to this genetic source.
“Resistance from the existing mechanism is starting to break down,” Nguyen said, “so the next several years, that is going to continue, and that makes this crucial to find additional resistance genes and incorporate them into new varieties for the farmers.”
With support from a $749,985 USDA National Institute of Food and Agriculture grant, Nguyen and his team have identified what they believe is a new resistance mechanism — an alternative genetic source. They are now using gene-editing techniques to express this gene, with hopes to understand the alternate genetic mechanism of SCN resistance which will be integrated into soybean breeding program to develop new SCN-resistant soybean varieties . The project is carried out in collaboration with Gunvant Patil, Assistant Professor at Texas Tech University — a former post-doctoral scientist in Nguyen’s lab.
“Because we’re using gene-editing methods, regulatory hurdles are lower, allowing us to accelerate this critical work,” Nguyen explained. “This will expand the genetic diversity of soybean breeding pools. Eventually, we can stack this new gene with existing resistance genes to create more durable plants, making it much harder for SCN to adapt and overcome.”
Source : missouri.edu