ENDOPHYTES OF CATHARANTHUS ROSEUS: A POTENTIAL SOURCE OF PLANT GROWTH PROMOTERS AND ANTIMICROBIAL COMPOUNDS

Abstract

The present study was undertaken to isolate bacterial and fungal endophytes from medicinal plant- Catharanthus roseus (Periwinkle). A total of 13 endophytic bacterial isolates were obtained. The bacterial isolates were screened for the production of plant growth promoters (Indole Acetic Acid, nitrogen fixation & phosphate solubilization) as well as antimicrobial agents against potent human pathogens. Among the isolates, 11 bacterial isolates produced Indole-3-acetic acid (concentration ranging 11-74 μg/ml), 3 isolates were able to fix nitrogen and 3 solubilize insoluble tri-calcium phosphate in vitro. In primary screening, the extracts of 5 endophytic isolates appeared to have antimicrobial activity against 3 pathogens ( E.coli, Staphylococcus sp., Vibrio sp. ) in vitro assayed by agar well diffusion method.