STUDY ON THE GROWTH OF ALEXANDRIUM TAMARENSE BALECH

The present study was to determine the effects of water temperature, nitrogen and phosphorus concentrations, vitamin and antibiotic concentrationson the growth of toxic Alexandrium tanarense(Hong Kong Chain ò-under experimental conditions.The strains of Alexandrium tamarense was isolated in 1998 from Hong Kong sea area where harmful algal blooms(HAB-had frequently occurred, some of which were highly toxic.The results showed that its optimum growth condition was at 21-25℃, 882-1765Lmol N/L and 18-72Lmol P/L respect ively.When temperature was 21℃, nitrogen concentration was 1765Lmol/L and phosphorus concentration was 72Lmol/L, the specific growth rate calculated from microscopic cell counts over the exponential phase of growth attained the higher value of 0.21, 0.28 and 0.28 d-1 respectively.Incorporated vitamin made up of B1, B6 and B12 had positive effect on the growth of Alexandrium tamarense when the contents of them ranged from 0, 0 and 0Lg/L to 500, 500 and 110Lg/L.The dinoflagellate got their maximal growth rate 0.26 d-1 at the highest vitamin concentrations.While the antib-i otic( liquid of ampicillin-exceeded 50U/mL had obviously inhibition on it.The cellule algae of Alexandrium tamarense was observed in the culture containing ant ibiotic, and the forming mechanism required extended studies.