Identification and characterisation of the dominant Pseudo-nitzschia species (Bacillariophyceae) along the NE Spanish coast (Catalonia, NW Mediterranean)

摘要: Potentially toxic species of the genus Pseudo-nitzschia were studied along Spanish NW Mediterranean coast from January 2005 to May 2006. Observation in electron microscopy revealed presence brasiliana, P. calliantha, delicatissima, fraudulenta, multistriata and pungens. Several strains isolated coastal waters their clonal cultures compared by combined techniques, including light internal transcribed spacer (ITS-1, 5.8S ITS-2) rDNA sequencing. Cultured isolates submitted HPLC analysis pigments evaluate possibility taxonomic discriminations means a simple chemotaxonomic approach. The showed high cell concentrations during most year, but population initiated sharp decline at all stations period between April May. delicatissima with calliantha found northern February April, southern August November. brasiliana only occasionally detected region. None environmental variables considered was significant explain observed spatial temporal distributions area studied. Differences growth rate yield indicate that biotic factors may play role distributional patterns.