Effects of Water Temperature, Salinity and Irradiance on the Growth of the Toxic Dinoflagellate, Gymnodinium catenatum (Graham) Isolated from Yeosuhae Bay, Korea

摘要

A chain-forming toxic din flagellate, Gymnodinium catenatum (Graham) was known as a paralytic toxin-producer among Gymnodinoid group. In the study, the effects of water temperature, salinity and irradiance on the growth of G. catenatum isolated from Yeosuhae Bay, Korea were investigated. Water temperature range in which G. catenatum showed specific growth rate higher than 0.3 day were above about 18 . However, salinity did not have such an effect on growth of G. catenatum. The maximum growth rate (0.5 day ) was obtained at 25 and 30 psu. The specific growth rate (u) expressed as a polynomial equation as functions of temperature (T; ) and salinity (S; psu) was = 0.005·T - 0.0001164 T - 0.063-S + 0.005-S - 0.00007608-S - 0.003-T-S + 0.00005308-T -S. Thus, in aspects of water temperature and salinity, the species may be expected to survive in most Korean coastal waters from early summer to autumn. The irradiance-growth curve was described as = 0.16 (I - 10.4)/(1 + 21.8) at 18 and 30 psu, indicating a half-saturation (Ks) photon flux density (PFD) of 42.6 mol m and compensation PFD (I ) of 10.4 mol m . These characteristic responses to irradiance suggest that G. catenatum can reside at the sub-surface.