Identification Symptoms

  • One or more berries of a cluster show signs of decay just before harvest. The decay may progress to include most of the berries in a cluster. The infected fruit may become covered with a grayish-tan powder containing the spores of the fungus.
  • Berry stems and cluster stems may be invaded, causing them to shrivel.
  • When the fungus decays berries low in sugar, the rotting berry has a sour odor and taste.
  • If the berries are nearly mature and have a high sugar content, the decaying berry is quite firm, dry, and somewhat sweetish to the taste. Berries that have split or have been punctured often are attacked by other organisms, resulting in a sour or moldy decay.