black rust

American  

noun

Plant Pathology.

1. any of several diseases of plants caused by rusts and characterized by black discoloration resulting from the fungal teliospores.

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black rust British  

noun

1. a stage in any of several diseases of cereals and grasses caused by rust fungi in which black masses of spores appear on the stems or leaves

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Etymology

Origin of black rust

An Americanism dating back to 1780–90

Example Sentences

See Examples For:

black rust

Reports last week were that black rust and weather conditions had cut the Canadian yield from last year's 400 million bushels to 200 or 225 million.

From Time Magazine Archive

Next day, however, despite reports of black rust in Kansas, the price of July wheat dropped from $1.11 to $1.08 per bu.

From Time Magazine Archive

In some spots there had been drought, in others black rust, in still others grasshoppers.

From Time Magazine Archive

War demands, the unfavorable United States Government report and rumors of black rust are making for a bullish condition.

From Deep Furrows by Moorhouse, Hopkins

J, part of a corn leaf, with black rust, natural size.

From Elements of Structural and Systematic Botany For High Schools and Elementary College Courses by Campbell, Douglas Houghton