Spatial distribution of toxic Alexandrium tamiyavanichii (Dinophyceae) in the southeastern South China Sea-Sulu Sea: A molecular-based assessment using real-time quantitative PCR (qPCR) assay

摘要: In this study, a quantitative real-time PCR (qPCR) assay targeting the second internal transcribed spacer (ITS2) of nuclear-encoded ribosomal RNA gene (rDNA) was developed for Alexandrium tamiyavanichii, harmful tropical marine dinoflagellate. This species is concern because it produces toxins that cause paralytic shellfish poisoning (PSP). The qPCR employed hydrolysis probe technology and showed high specificity, with detection limit 102 copies (less than one cell equivalent). Using assay, spatial distribution A. tamiyavanichii assessed, first time, in southeastern South China Sea Sulu Sea. Plankton samples were collected from 71 stations during scientific cruise Research Vessel Sonne as part joint EU project on Stratosphere ozone: Halogens Varying Atmosphere (SHIVA), conducted November 2011. highest densities detected offshore Kuching, southern Borneo (150 cells l−1) exceeded threshold level 20–40 l−1 where bioaccumulation PSP by concern. patchy horizontally concentrations found mainly Borneo, heterogeneous vertical observed above pycnocline. proved its applicability, specificity sensitivity, provides an alternative implementation tool microalgae monitoring programs.