Bacterial diversity studies in hypersaline soil often yield novel organisms and contribute to our understanding of this extreme environment. Soil from Mad Boon is previously uncharacterized, with dense mangrove forest in one side and hypersaline soil in another side of backwater located in Southeast coast of Tamil Nadu, India. We surveyed to characterize the structure and diversity of the bacterial community. Samples were collected in a partially vegetated upland, exposed backwater sedimentation and water-logged location. In this study, we investigate the bacterial community structure using pyrosequence analysis of the V5- V9 gene region. After quality checks a total of 3919, 7298 and 7399 reads were obtained. About 42 phyla were observed, among them Proteobacteria were dominant phylum followed by Acidobacteria, Firmicutes and Chloroflexi. Classes including Deltaproteobacteria and Gammaproteobacteriawere observed. All sequences generated in this study were submitted to NCBI SRA under the accession numbers SRR627695, SRR63011 and SRR631012.

We have created barcode library for common Argulus spp. infecting Carassius auratus, which could also be used to identify premature forms of Argulus spp. even by non-professionals. Infected C. auratus was examined and purchased from ornamental fish-trading centers and the adult life stage of Argulus spp. was identified and DNA barcoded. The eggs of Argulus spp. were collected using bottle implants. The collected eggs are barcoded and precisely identified by matching with the adult sequences. Four species of adult Argulus spp. were identified, namely Argulus japonicus, Argulus indicus, Argulus siamensis, and Argulus foliaceus. Precise identification of egg samples was done by two different analyses, namely (i) BLAST analysis and (ii) phylogenetic clustering of adults and eggs. All egg samples including the control were precisely identified by BLAST analysis and the results are consistent with phylogenetic clustering of adult and egg’s DNA barcodes. In order to establish the DNA barcode technology for the identification of all Argulus spp and its premature forms, the development of full-fledged barcode library that includes all species of this genus is very important for the benefit of ornamental fish industries.

Strengthening the DNA barcode database is important for a species level identification, which was lacking for seaweeds. We made an effort to collect and barcode seaweeds occurring along Southeast coast of India. We barcoded 31 seaweeds species belonging to 21 genera, 14 family, 12 order of 3 phyla ( viz. , Chlorophyta, Phaeophyta and Rhodophyta). We found 10 species in 3 phyla and 2 genera ( Anthophycus and Chnoospora ) of Phaeophyta were barcoded for the first time. Uncorrected p-distance calculated using K2P, nucleotide diversity and Tajima’s test statistics reveals highest values among the species of Chlorophyta. Over all K2P distance was 0.36. The present study revealed the potentiality of rbcL gene sequences in identification of all 3 phyla of seaweeds. We also found that the present barcode reference libraries (GenBank and BOLD) were insufficient in seaweeds identification and more efforts were needed for strengthening local seaweed barcode library to benefit rapids developing field such as environmental DNA barcoding. We also show that the constructed barcode library could aid various industrial experts involved in seaweed bio-resource exploration and taxonomy/non-taxonomic researches involved in climate, agriculture and epigenetics research in precise seaweed identification. Since the rise of modern high-throughput sequencing technologies is significantly altering bio-monitoring applications and surveys, reference datasets such as ours will become essential in ecosystem’s health assessment and monitoring.