Nucleic acid spot hybridization based species-specific detection of Sclerotium rolfsii associated with collar rot disease of Amorphophallus paeoniifolius.

Collar rot is one of the most destructive and prevalent disease of Amorphophallus paeoniifolius, resulting in heavy yield losses. The causative organism, Sclerotium rolfsii is a soil-borne polyphagous fungus characterized by prolific growth and ability to produce persistent sclerotia. The pathogen propagules surviving in soil and planting material are the major sources of inoculum. This study presents the suitability of DNA hybridization technique for species specific detection of S. rolfsii in soil and planting material. The detection limit of the probe was 10-15 pg of pure pathogen DNA. The developed probe was found to be highly specific and could be used for accurate identification of pathogen up to the species level. The protocol was standardized for detection of the pathogen in naturally infected field samples.