Rhizospheric metagenome of the medicinal fern Christella dentata from saline environment of Indian Sundarbans
Vineet Vishal and Sabdar Rahaman*
Department of Botany, Bangabasi Evening College, Kolkata - 700009 {India} *Corresponding author: drsrahaman@gmail.com
ABSTRACT
The soil microbiome plays a key role in controlling carbon and nutrient cycle in terrestrial ecosystems, affecting plant productivityand stress tolerance. Over time, bacterial communities have evolved mechanisms to endure stresses. However, the mechanism governing these strategies is not entirely known. A cloud-based microbial bioinformatics approach was utilized to investigate the diversity and probable ecological roles of uncultured bacterial communities in the active rhizospheric zone of the medicinal fern Christella dentata {Forssk {Brownsey} & Jermy. The rhizospheric soil samples were collected from the farthest island village Kumirmari, in the Gosaba block of Indian Sundarbans {22° 13' 11.0" N, 88° 55' 03.3" E}. Uncultured bacteria in medicinal ferns were detected using the V3-V4 hypervariable amplicon region of the 16S rRNA gene and mapped using the SI LVA 138.1 Small Subunit rRNA Database. Acloud-based microbial bioinformatics study indicated a high richness of operational taxonomic units {673 OTUs}, with Proteobacteria {35.46%}, Actinobacteriota {25.54%}, Firmicutes {20.86},Acidobacteriota {4.13%}, andBacteroidota {3.14%} clusteredand over-distributed in the rhizosphere. Gammaproteobacteria {28.27%}, Actinobacteria {23.42}, and Bacilli {19.78%} displayed substantial phylogenetic redundancy. The most abundant pathways were membrane transporter, ATP-binding cassette transporter, and signal transduction. This plant promotingrhizospheric bacteria trigger osmolyteaccumulation, maintain ion homeostasis, boost oxidative stress resilience, biofilm development, and phytohormone secretion whenever they are exposed to an adverse environment like salinity.