black rust

noun

, Plant Pathology.

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

black rust

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

Word History and Origins

Origin of black rust¹

An Americanism dating back to 1780–90

Example Sentences

Dreadful effects are said to be produced by a species of black rust which attacks the large South of Europe reed, Arundo donax.

From Project Gutenberg

In Britain it has been almost universally banished from hedgerows, owing to its connection with the black rust of wheat.

From Project Gutenberg