Open Access Library Journal 2018, Volume 5, e4388 ISSN Online: 2333-9721 ISSN Print: 2333-9705 DOI: 10.4236/oalib.1104388 Mar. 5, 2018 1 Open Access Library Journal Epiphytic Bacterial Communities in Seagrass Meadows of Oligotrophic Waters of Andaman Sea Amrit Kumar Mishra * , Raju Mohanraju Department of Ocean Studies and Marine Biology, School of Life Sciences, Pondicherry University, Brookshabad Campus, Port Blair, India Abstract The epiphytic microbial communities of seagrass (Cymodocea rotundata and Thalassia testudinum) along with sediments and seawater of the seagrass eco- system of Andaman Sea were assessed for heterotrophic bacterial communi- ties. Young leaves of C. nodosa and T. testudinum sediments and water sam- ples were collected from two different locations at Burmanala and Havelock island. Young leaves were swabbed and transferred into Alkaline peptone wa- ter along with 1 gm of sediments and 1 ml of seawater for initial microbial en- richments, followed by culture of microbes in Salt Yeast Extract Agar. Thi- osulphate Citrate Bile Salt agar was used for seagrass leaves, sediments and water for culturing of Vibrio like microbes. The observed colonies were mor- phologically (colour) identified first and then further identification was done by Gram staining and various biochemical tests. Sediment bacterial count was 10-fold higher than seagrass and water column communities. Morphologically 29% of total bacterial colonies identified were of grey and white colour. T. testudinum bacterial epiphytes were 2-fold higher than C. rotundata commu- nities. Gram negative bacterial isolates of Pseudomonas, Vibrios and Aero- monas dominated the bacterial colonies than gram positive bacteria of Bacil- lus and Micrococcus. Vibrios were only observed on seagrass leaves. Seagrass harboured more gram positive bacterial colonies than gram negative, which were dominated in the sediments of seagrass ecosystem. The bacterial com- munities of landward site of Burmanala and Havelock were similar whereas 2-fold higher communities were observed at the seaward site of Havelock site on T. testudinum. Seagrass ecosystem bacterial epiphytic communities are di- verse in oligotrophic waters. Subject Areas Marine Biology How to cite this paper: Mishra, A.K. and Mohanraju, R. (2018) Epiphytic Bacterial Communities in Seagrass Meadows of Oligotrophic Waters of Andaman Sea. Open Access Library Journal, 5: e4388. https://doi.org/10.4236/oalib.1104388 Received: January 31, 2018 Accepted: March 2, 2018 Published: March 5, 2018 Copyright © 2018 by authors and Open Access Library Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access