BLACKSBURG, Oct. 2, 2002. - Mother Nature put it in the humble soybean. Well-intentioned humans, in our quest to create the perfect bean, somehow took it out. Now, a team of Virginia Tech scientists will spend millions trying to track down the genes that give wild soybeans the strength to fight off root rot - hoping to restore that natural disease-resistance in commercial soybeans.
The National Science Foundation has awarded $6.7 million to researchers at the Virginia Bioinformatics Institute, several other Tech departments and Ohio State University to study the genes that give some varieties of soybeans a natural resistance to root rot.
"In many cases, it's actually been bred out of the crops as we've improved the plants," said Brett Tyler, the Virginia Bioinformatics Institute professor leading the multidisciplinary group. The grant, which is spread out over five years, is one of the largest received by the institute since it opened two years ago.
Caused by a pathogen known as Phytophthora sojae, root rot costs farmers worldwide an estimated $1 billion to $2 billion in damage annually, with much of that loss incurred in the United States. As its common name implies, root rot chews away at adult soybean plants' roots, significantly reducing the yield. The pathogen also kills soybean seedlings soon after planting. Farmers and plant breeders have tried many approaches to prevent the disease in recent years, but with minimal success. Unlike some pests, which can be fought off by introducing a single gene into a crop, root rot can be deterred only by a combination of genes acting together. Figuring out the right combination is the difficult part, Tyler said.
Tyler estimates that about 10 of the soybean's 30,000 genes are probably responsible for the plant's natural resistance to root rot. Such a task would have been near impossible before the recent rise of bioinformatics, the use of supercomputers to make sense of vast amounts of data.
The group hopes its work can eventually be used to breed the natural defenses into commercial soybean stocks, thereby making U.S. farmers more competitive and reducing the need for fungicides. If successful in isolating the genes, the team's work could help researchers fight off related pathogens that cause up to $20 billion in damage to everything from potatoes and tomatoes to cocoa trees.
Tyler says he believes his group - which includes plant pathologists, mathematicians and soil scientists - was chosen by the National Science Foundation because of its varied composition.
"We all bring different areas of expertise to the project," Tyler said. "The project probably wouldn't be possible at all without all of those pieces."
October 01, 2002