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a smut species that resembles ergot of rye in its metabolic action; its black spores on the ears of corn are dispersed by wind and can cause contamination of laboratory cultures.
a mold which grows commonly on the foliage and ears of the maize plant. Possibly related to cornstalk poisoning of cattle. The related smut on barley (Ustilago hordei) is suspected to cause abortion in ruminants.