First Report of Ustilago bullata on Meadow Bromegrass in Saskatchewan, Canada. B. D. Gossen, Agriculture Canada Research Station, Saskatoon, Sask. S7N 0X2. G. D. Jesperson, Saskatchewan Agriculture and Food, Regina, Sask, S4S 0B1. Plant Dis. 74:615. Accepted for publication 22 March 1990. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/PD-74-0615E.
Meadow bromegrass (Bromus riparius Rehm.) has been introduced
recently into the Canadian prairies and is rapidly gaining acceptance
as a pasture grass for use in the northern grain belt and under irrigation.
In 1989, head smut caused by Ustilago bullata Berk. in Hook. was
noted in Saskatchewan seed fields at Big River, Nipawin, and Lashburn,
grown from seed (cv. Regar) imported fron the United States.
Seed fields of Paddock, a recently released Canadian cultivar, at Saskatoon,
Melfort, and Nipawin were also infested with the pathogen.
All the meadow bromegrass cultivars registered in Canada (Regar,
Fleet, and Paddock) are derived from susceptible parental lines, and
there are no fungicides registered for control of this pathogen in
Canada. The presence of this pathogen may jeopardize the expansion
in utilization of this promising forage grass. Head smut has been
noted on native and weedy grasses in Saskatchewan (1), but this is
the first report of its occurrence on an economically important species
in western Canada, and it may represent the introduction of a new
race of the pathogen into Canada.