Phenotypic and Molecular Characterization of Endophytic Bacteria Isolated from Banana

Several species of endophytic bacteria has been reported from various plants. In the present study, samples of roots, rhizome, pseudostem, petiole and leaves of healthy Banana plant were collected from variety Yangambi km5 (AAA). In total, 38 endophytic bacteria were isolated. Amongst 16 isolates were selected based on compatibility by cross streak method. The 16 strains tested by paper disc method, Lf4, Lf5, Lf10, Pt4 and Ps7 showed inhibitory effects against Pectobaterium carotovorum subsp. carotovorum under in vitro conditions. The Lf4 and Lf5 showed similar results for the biochemical characteristics studied. The isolate Lf10 showed a slight difference with regard to oxidase test, Methyl red, Urease test and H2S production. The isolates Pt4 and Ps7 showed similar result except nitrate reduction, KOH test and Pigment production. Bacillus subtilis (Bs) strain (culture collected from Department of Plant pathology, TNAU) was used as reference culture. The total DNA extracted from selected five isolates was identified by partial sequencing of the 16S rRNA gene and phylogenetic tree was constructed using MEGA 6.0. The results confirmed that isolates Lf4 and Lf5 were Bacillus subtilis, isolate Lf10 was an Ochrobactrum daejeonense, isolate Pt4 was an Achromobacter xylosoxidans and Ps7 was a Pseudomonas aeruginosa. The study revealed that all the five strains have biocontrol potential against soft rot pathogen.