Grey leaf spot (Pseudocercospora mori)

Period of occurrence

The disease occurs generally during the winter months from September and continues up to next February.

Identification of the disease

  1. The disease is characterized by small to medium size velvety gray to black spots appearing on the lower surface of the older leaves.
  2. The spots are indistinct on upper surface, more conspicuous on the lower surface.
  3. The spots are brown, angular or spreading (particularly along leaf margins) and restricted by the larger veins, up to 7mm wide.
  4. Later, the spots cover whole lower surface. 
  5. Severely infected leaves turn yellowish/ dark and defoliate prematurely.
  6. Conidia are pale olivaceous, straight or curved and septate.


                                                 Infected leaf                      Enlarged spots                      Conidia and conidiophores



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