International Team Uncovers How Wheat Lost Battle Against Blast

Researchers, including a plant pathologist from the University of Kentucky (UK) have uncovered an important link to wheat blast, a devastating disease. Wheat in North America has not been susceptible to wheat blast, but in 2011, UK researchers discovered a single diseased wheat head in a research plot at the UK Research and Education Center in Princeton, Kentucky. Wheat blast epidemic swept through Bangladesh in 2016, and again this year.

Research conducted at the UK Department of Plant Pathology revealed that the pathogen collected in 2011 is genetically distinct from South American wheat blast. It is very closely related to strains found on annual ryegrass and tall fescue in the U.S., suggesting that the 2011 incident arose via a ‘"host jump" from forage grasses to wheat. The group also found that the 2016 Bangladeshi epidemic very likely arose through the introduction of a South American strain of the fungus.

UK plant pathologist Mark Farman, together with collaborators from Japan, found that the 2011 wheat blast strain experienced a mutation in a key gene that codes for a protein that is normally recognized by wheat cultivars possessing a key blast resistance protein. The mutation compromises the "good" protein, and allows the fungus to escape the wheat resistance response by avoiding recognition. "This information will help spur the development of crop varieties with more durable resistance," Farman said.

For more, read the University of Kentucky News.