Widespread Occurrence of Ergot in Upper Midwestern U.S. Barley, 2005

Ergot, caused by Claviceps purpurea (Fr.) Tul., occurs every year on cereals and grasses in North Dakota, but the occurrence on barley (Hordeum vugare L) is generally sporadic with a very low incidence of sclerotia. Disease surveys conducted during the 2005 growing season revealed an unusually widespread occurrence. This is of concern since barley production in North Dakota was estimated at 1.25 million metric tons, 27% of the total 2005 U.S. production. Barley samples (n = 304, ~0.50 kg) collected in all crop-reporting districts of North Dakota, northwestern Minnesota, and northeastern Montana, as part of an annual regional survey of barley crop quality (4), were examined for sclerotia. All barley samples were cleaned for dockage, and ergot (% [w/w]) was estimated on subsamples of ~100 g from a sample divider. Of all barley samples collected, 62% contained ergots. The regional average for ergot infested kernels was 0.06%, and samples ranged from