Isolation, Identification, and Pathogenicity of Sclerotium rolfsii (Sacc.) Causing Collar Rot in Chickpea

Sclerotium rolfsii (Sacc.) is a detrimental soil-borne fungus responsible for collar rot in chickpea. We conducted an experiment including the isolation, purification, identification, and pathogenicity assessment of fungi from infected plant materials. The plants appear typical symptoms such as complete leaf abscission, browning, desiccation, and often remain attached to the dead stem. The mycelium of the pathogen proliferates over the affected tissue and adjacent soil, creating a white mat of mycelial threads interspersed with characteristic sclerotia, ranging from brown to dark brown and resembling mustard seeds in size. Collar rot samples were collected and sent to the laboratory for isolation. The fungus was isolated and grown on Potato Dextrose Agar (PDA) media. The pathogenicity tests were validated by adhering to Koch's postulates and used three inoculation techniques. The seed and soil inoculation approach demonstrated significant efficacy, resulting in the greatest disease incidence (71.05%) and reduced seed germination (74.90%). This research highlights the impact of S. rolfsii on chickpea crops, offering insights into its pathogenicity and management strategies. Understanding its infection mechanisms can help develop effective control measures to enhance chickpea yield and sustainability.