Pyrosequencing-Based Seasonal Observation of Prokaryotic Diversity in Pneumatophore-Associated Soil of Avicennia marina.

Pneumatophores are aerial roots developing from the main roots of mangrove plants away from the gravity. The below ground pneumatophore-associated soil prokaryotic community of Avicennia marina was studied by amplicon pyrosequencing (39,378 reads) during monsoon and summer seasons. Apart from the most dominant phylum Proteobacteria in both seasons, the second most were Acidobacteria (summer) and Cyanobacteria/Chloroplast (monsoon). Similarly, Acidobacteria_Gp10 and Cyanobacteria were the second most abundant at class level during summer and monsoon, respectively. Archaeal phylum Thaumarchaeota was the most abundant followed by Crenarchaeota and Euryarchaeota. The classes detected in our study were Thermoprotei, Halobacteria, and Methanomicrobia. The highest richness and diversity were observed during summer for bacteria, whereas the same phenomena for archaea in monsoon at 97% sequence similarity. To the best of our knowledge, this is the first attempt to catalog the prokaryotic diversity of pnueumatophore-associated soil.