For the isolation of the collar rot pathogen, sclerotia of
S. rolfsii were collected from pseudostems of
Amorphophallus showing typical symptoms of collar rot
in the field, surface sterilized in 0.1% mercuric chloride
solution, washed thrice thoroughly with the distilled
sterilized water and placed in petriplates having PDA
medium at room temperature (28±4oC ).