Vol. 11, Issue 11 (2022)

Inflorescence die-back and leaf spot disease is an economically important disease of areca nut across the world. The causal agent of the disease i.e., Colletotrichum gloeosporioides has often been confused with other Colletotrichum species, especially C. acutatum. To confirm the disease roving survey was conducted in major areca nut growing districts viz. Chikkamagaluru, Shivamogga and Davanagere of Karnataka state. Among the different pathogen isolates isolated, four isolates were characterized through morphological and molecular means. The data revealed that, all the isolates were found to be C. gloeosporioides and exhibited greyish white colony colour, whereas the reverse side appeared white to dark grey as well as orange colour. The conidia were cylindrical with both apices rounded or with one apex rounded and the other end partly pointed. The polymerase chain reaction (PCR) assay with the C. gloeosporioides using species-specific primer (Cg INT) with ITS4 yielded a single band of 450bp. Nucleotide sequences of the Cg INT region of the ribosomal DNA of all isolates had 99% homology with C. gloeosporioides. Thus, the present study proved the association of C. gloeosporioides in causing inflorescence die-back and leaf spot disease through detached leaf technique under In-vitro.