Permalink : http://hdl.handle.net/2115/44760

KEYWORDS : Red tide;Dinoflagellate;Hetrocapsa circularisquama;Heterocapsa triquetra;Karenia mikimotoi;Selenium requirement;Selenite;Selenate;Growth

Trace elements are known to restrict phytoplankton growth in the sea. Selenium is one of important trace elements and known to be an essential element for certain harmful algae. In this study,we investigated selenium requirements for the growth of harmful algal boom forming three dinoflagellates, Heterocapsa circularisquama, H. triquetra and Karenia mikimotoi about two chemical forms of inorganic selenium (selenite and selenate)using an artificial synthetic medium of remodified ASP7. These three dinoflagellate species required selenium for growth as a form of selenite,but could not grow under a form of selenate. Morphological changes with selenite depletion like selenium requiring centric diatom were not detected so far by microscopic observation.