PHYLOGENETIC ANALYSIS OF COLLETOTRICHUM FALCATUM ISOLATES CAUSING RED ROT IN SUGARCANE

Abstract

The fungal pathogen Colletotrichum falcatum, causing red rot, exhibits enormous variation. Representative isolates of C. falcatum collected from major red rot endemic regions in the country were characterized by cultural, pathological and molecular methods using the 5.8s-ITS region. Phylogenetic analysis of ITS sequences confirmed the divergent and unique nature of C. falcatum from other Colletotrichum spp. and separated the Indian isolates under three distinct molecular groups as Group I, II, and III. Although the dark coloured, non-sporulating least virulent types similar to isolates of other countries were distinguished in Group III, diversity among Group I and II was not much supported by cultural or pathogenicity patterns. However, overall correlation could be made with respect to phenotypic and genotypic characters based on their predominance in each group. This is the first attempt to group a large collection of C. falcatum isolates using molecular approach and correlate with other traits.