Seasonal variations in the culturable diversity and population density of the total heterotrophic and pathogenic bacteria, in the coastal waters of the Andaman Sea, India

摘要

Present study examined the seasonal variations of total heterotrophic and pathogenic bacterial diversity of the coastal waters of the Andaman Sea in the Havelock island. In the non-moonson season, 22 strains of total hetrotrophic bacteria (TUB) belonging to 8 genera, were isolated from water. Escherichia (23%) was dominant, followed by Pseudomonas (18%), Vibrio (14%), Enterococcus (14%), Salmonella (9%), Aeromonas (9%), Klebsiella (9%) and Cornebacterium (4%). In the monsoon season, 29 strains of THB belonging to 12 genera, were isolated. Vibrio (14%), Micrococcus (14%) and Klebsiella (14%) were dominant and contributed equally to the percent composition followed by Escherichia (10%), Streptococcus(10%), Enterococcus (10%), Pseudomonas (7%), Aeromonas (7%), Salmonella (4%), Shigella (4%), Flavobacterium (3%) and Staphylococcus (3%). Population density of THB varied from 43 X10(5) CFU mL(-1) to 182 X10(5) CFU mL(-1) in the non-monsoon season. In the monsoon season, it varied from 93 X10(5) CFU mL(-1) to 365 X10(5) CFU mL(-1). In the monsoon, THB diversity including pathogens was higher as monsoon would provide with a favourable microenvironment for the higher growth of THB and pathogenic bacteria.