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definitions

black root rot

noun Plant Pathology.
  1. any of several diseases of plants characterized by black or brown lesions on the root.
  2. a common disease of the apple caused by the fungus Xylaria mali.
  3. a disease of tobacco caused by the fungus Thielaviopsis basicola and characterized by retarded growth and wilting.

Origin of black root rot

First recorded in 1905–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018