When disease threatened Missouri’s biggest cash crop, MU researchers realized they had to build a better, stronger soybean.
“Right now we really don’t have any practical way to treat (soybean rust),” said Paul Beuselinck, an MU adjunct professor of agronomy and a member of the National Center for Soybean Biotechnology, located in MU’s Life Sciences Center.
The center’s researchers, most of whom are MU professors, are trying to create a soybean plant resistant to Asian soybean rust, a disease they expect Missouri farmers will have to battle for the first time in May. It was discovered in southeastern Missouri in November.
“We really don’t know how bad the disease is going to be,” Beuselinck said. “This is a new thing for all of us.”
Although rust is a new challenge, MU professors have been experimenting with plants’ genetic composition for roughly 100 years, Beuselinck said. Soybeans — with uses ranging from animal feed to bio-diesel fuel — is a relatively recent crop.
Beuselinck said the changes necessary to produce resistance wouldn’t affect the bean’s taste or usefulness.
Plants infected with soybean rust develop small, yellow pustules on their leaves, which can burst and further spread the disease. It thrives on moisture and moderate temperatures, and infected plants cannot be harvested. MU professor of Agronomy David Sleper, also a member of the NCSB, said the effects can be debilitating.
“It’s a very troubling disease,” he said. “There’s a potential loss of 80 percent of your crop if you have a severe infestation.”
MU Extension plant pathologist Laura Sweets said with hot, dry weather conditions that inhibit the spread of rust, less than 20 percent of a farmer’s crop could be affected.
“It’s that uncertainty that has everyone concerned,” she said.
Dale Ludwig, the executive director and CEO of the Missouri Soybean Association and the Missouri Soybean Merchandising Council, doesn’t foresee a massive blow to soybean farmers.
“To start saying the sky is falling, where we could see 50 percent reductions in yield, is not very likely,” he said.
There are fungicides that can kill the rust, but Beuselinck said they wouldn’t be practical in the event of a serious infestation. Spraying one acre of soybean crops with fungicide costs roughly $20.
Missouri has 5 million acres of soybean crops, making it one of the top states for soybean farming. Missouri’s soybeans are worth roughly $1 billion, Sleper said.
Missouri farmers harvested an average 46 bushels per acre in 2004, a state record.
In February, scientists from the NCSB will send samples of soybean seeds to Vietnam to be planted. The growing season starts earlier there, and rust is also a problem. The exercise is designed to see whether any existing strands are resistant. Sleper is pessimistic.
“I don’t think we’re going to get lucky,” he said.
Without a resistant strain, Sleper and the NCSB will continue trying to create a soybean that is resistant.
Ludwig said rust is a serious problem, but that a resistant strain of plants probably won’t come in time for the 2005 growing season.
“I think those things are something you should do, although we’re talking about a best-case scenario of maybe seven years in order to have varieties that are resistant to rust,” he said.
Sleper acknowledged that the project could take years and said the cost of such an effort is nearly impossible to estimate.
“It depends how many dead ends we go down,” he said.