The epiphytic bacterial community prevalent on ethnomedicinal plant surfaces were studied
for their diversity, niche localization and colonization using the micrographical and
molecular approaches. Scanning electron microscopy (SEM) revealed the presence of large
aggregates of bacterial communities. The bacterial localization was observed in the grooves
along the veins, stomata and near the trichomes of leaves and along the root hairs. A total of
20 cultivable epiphytes were characterized which were analyzed for richness, evenness and
diversity indices. Species belonging to the genera Bacillus and Pseudomonas were the most
abundant. Bacillus thuringiensis was the most prevalent epiphyte with the ability to form
biofilm, as a mode of adaptation to environmental stresses. Biofilm formation explains the
potential importance of cooperative interactions of epiphytes among both homogeneous
and heterogeneous populations observed under SEM and influencing the development of
microbial communities. The study has revealed a definite pattern in the diversity of culturable
epiphytic bacteria, host-dependent colonization, microhabitatlocalization and biofilm
formation which play a significant role in plant–microbe interaction