On Tap: Genomic Sequence Of An Enemy Of Beer And Bread

The genomic sequence of the fungal plant pathogen, Fusarium graminearum, has been completed, providing scientists a roadmap to combating a fungus that infects wheat and barley crops, rendering them unusable.

"We have enough to do a tremendous amount of good work," said Frances Trail, MSU associate professor of plant biology. "Now we can begin to unravel mechanisms to combat this fungus which is a devastating problem in Michigan, the Midwest and all over the world."

This fungus is a serious pathogen of wheat and barley in Michigan and throughout the Midwest. It causes Fusarium head blight, which reduces grain yields, and taints grain with mycotoxins that have been found to be detrimental to human and animal health.

F. graminearum also is a pox to beer producers. Malting creates a fungus friendly environment, and barley infected with the fungus produces beer with a vast excess of foam. As a result, the malting barley industry has a zero tolerance for this fungus.

The fungus comes with a steep price tag – rendering crops worthless. For example, head blight outbreaks in the 1990s cost U.S. agriculture $3 billion.

F. graminearum begins its blighting ways as pinprick-sized pods that spit spores into the air. The spores float over grain fields, landing on flowering wheat and barley. The spores grow into the wheat flowers. The often cool, wet weather of the U.S. Midwest provides an ideal environment for the fungus to take hold.

The result:: fields of blight, identified by withered, bleached heads of grain. At harvest, many of the grains are shrunken and white, and harbor the mycotoxins.

"Classical control methods for blight just aren't working," Trail said. "Sequencing this fungus can be the beginning of designing new methods of control."

The F. graminearum sequencing project represents a partnership between MSU and the Whitehead Institute Center for Genome Research at the Massachusetts Institute of Technology, H. Corby Kistler at the U.S. Department of Agriculture, ARS Cereal Disease Lab of University of Minnesota and Jin-Rong Xu at Purdue University.

Researchers now will work to understand and annotate specific gene function within the sequence. In Trail's lab, work already has begun on specific genes that appear to control the firing mechanisms of the spore pods.

The project was funded by the National Research Initiative in the USDA's Cooperative State Research Education and Extension Service, and reviewed through the USDA/National Science Foundation Microbial Genome Sequencing Project.

The results of the project can be viewed at http://www.genome.wi.mit.edu/annotation/fungi/fusarium/index.html