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

In Flint, high blood levels of lead have been found in children in the mostly poor, black Rust Belt city of 100,000, where the crisis has led to allegations of environmental racism.

From US News

Colors tend to be white, gray, black, rust and dusty pink, with occasional forays into red, yellow or deep green.

From New York Times

And because Black Rust had impaired the spring wheat yield those thousands of bushels he raised, he had sold at a price so high that he had sufficient to redeem at last the land he was about to lose and money left for future development into the bargain.

From Project Gutenberg

Soon, the plant is enveloped in reddish-brown or black pustules, leading to the disease's other name, black rust.

From Nature

Hope on this score plus rumors of black rust last week jumped prices on the Chicago wheat exchange 4�� a bu. day after the report was issued.

From Time Magazine Archive