black rot

American  

noun

Plant Pathology.

1. any of several diseases of fruits and vegetables, characterized by black discoloration and decay of affected parts, caused by fungi, as Guignardia bidwellii, or bacteria, as Xanthomonas campestris.

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black rot British  

noun

1. any of various plant diseases of fruits and vegetables, producing blackening, rotting, and shrivelling and caused by bacteria (including Xanthomonas campestris ) and fungi (such as Physalospora malorum )

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Etymology

Origin of black rot

An Americanism dating back to 1840–50

Example Sentences

This wild grape is known for its naturally high sugar content, low acidity, and resistance to fruit cracking, as well as its tolerance to diseases such as black rot and ripe rot.

From Science Daily • Nov. 3, 2025

It is caused by excess soil moisture, characterized by a black rot that spreads from the roots and eventually kills the tree.

From Seattle Times • Jan. 10, 2023

We start shoveling, tipping clods of black rot into 16-gallon plastic bins, then relay the full buckets, man to man, to a 20-foot-long, five-and-a-half-foot-tall metal dumpster outside.

From Salon • May 30, 2020

He was, like the others, unsuccessful due to attacks of black rot and phylloxera.

From Salon • Jun. 3, 2018

One of the enemies we had to fight in the vineyard was the rot, the black rot, an imported disease of the grape that for a few years swept everything.

From My Boyhood by Burroughs, John