Sclerotium wilt/ Collar rot (Sclerotium rolfsii Sacc.)

Period of occurrence

The disease in very common in the mulberry nurseries during the rainy season (July- September)

Identification of the disease

  1. The disease is characterized by presence of dark brown to black water soaked spots on the collar region of the stem.
  2. The black water soaked spots encircle the stem and eventually more upward and downward regions.
  3. White mycelial mat with a large number of chocolate brown sclerotial bodies  will develop over the infected tissues.
  4. Sclerotia are ellipsoidal in shape and vary from 0.5 to 1.5 mm in size.
  5. Once the stem base is affected, the entire shoot drops down. 


 Infected plant                                    Mature sclerotia

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