|Fusarium head blight in the U.S.|
During the past decade, Fusarium head blight or scab of wheat and barley has been the plant disease with arguably the greatest impact on U.S. agriculture and society. The disease, caused by the fungal pathogen Fusarium graminearum, has reached epidemic proportions in the United States causing yield losses and price discounts resulting from reduced seed quality. Over 2.6 billion dollars have been lost to US agriculture during wheat scab epidemics in the 1990s (McMullen et al., 1998) having a devastating effect on farm communities in the upper Midwest (Windels, 2000). Moreover, the disease is increasingly becoming a threat to the world's food supply due to recent head blight outbreaks in Asia, Canada, Europe and South America (Dubin et al., 1997). The pathogen poses a two-fold threat: first, infested cereals show significant reduction in seed quality and yield due to discolored, shriveled "tombstone" kernels, and secondly, scabby grain is often contaminated with trichothecene and estrogenic mycotoxins (McMullen, et al., 1998), making it unsuitable for food or feed.