Can the diversity of Singapore Marine Planktonic Eukaryotes be uncovered using culture methods?

Phytoplankton have key ecological significance and are suited to be bioindicators. There is a need to improve conventional morphology-based biomonitoring approaches and evaluate metabarcoding as a biomonitoring tool. This study aims to understand the culturable diversity of phytoplankton from Singapore waters. Several isolation strategies were used, including serial dilution, flow cytometry cell-sorting and single-cell pipette isolation, on marine samples collected from Singapore and Johor Straits. Isolated strains were genetically characterized by 18s rRNA sequencing and sequences were phylogenetically analyzed. Sequences obtained were compared against environmental metabarcoding data. A total of 22 strains were isolated, spanning 4 divisions- Chlorophyta, Cryptophyta, Dinoflagellata, Ochrophyta. Phylogenetic analysis revealed that several strains represented uncultured sequences in databases. Comparison with metabarcoding data demonstrated that culture methods uncover diversity not detected by metabarcoding. Culture methods can uncover the diversity of phytoplankton in Singapore waters and should be a continuous effort, to improve biomonitoring approaches and applicability.Bachelor of Science in Biological Science