URBANA Approximately 55 percent of the horseradish produced in the United States is grown in the Collinsville, Ill., area, the self-proclaimed "Horseradish Capital of the World." The product is of such high quality that Europeans import it for gourmet and industrial use. But when crop sciences professor Mohammad Babadoost first arrived at the University of Illinois in 1999, he was told that growers had been experiencing significant yield reductions due to internal discoloring and root rot.
"If the roots are discolored, they are not accepted for processing," Babadoost said.
U of I researchers have been looking at various bacteria and fungi for more than 30 years, trying to identify the agents causing the problem. In the 1980s, they isolated a fungus called Verticillium dahlia, which was linked to horseradish disease at many locations in the United States.
Babadoost, however, was not convinced that this fungus alone was responsible for all the damage.
"When I came here, I realized that it's a serious problem, and I thought it could be a complex problem rather than a single-pathogen/single-disease problem," he said.
He was right. In 2004, he and his team determined that internal discoloration of horseradish roots is due to a disease complex caused by at least three fungi: Verticillium dahlia, Verticillium longisporum, and Fusarium solani.
"But I was still not completely convinced that that was the end of the story," he said. He was seeing a lot of root rot that did not appear to be caused by the identified pathogens.
He and his graduate student, JunMyoung Yu, carried out fungal isolations from horseradish roots from commercial fields in Illinois and Wisconsin. They first identified isolates to genus; those identified as Fusarium were further identified to species based on their morphological and molecular characteristics.
They selected 11 isolates that t
|Contact: Susan Jongeneel|
University of Illinois College of Agricultural, Consumer and Environmental Sciences