THE GROWTH OF UNICELLULAR ALGAE IN ARTIFICIAL AND ENRICHED SEA WATER MEDIA

Abstract

The growth of pure cultures of Dutialiella euchlora strains WHOI-1 and WHOI-2, Platymonas subcordiformis, Phaeodactylum tricormitum, Chlorella vulgaris, and Cyclotella meneghiniana was compared in two enriched sea water media and two artificial marine media. Three general patterns of growth were observed; the green flagellates grew the same in all media, Phaeodactylum and Chlorella grew more slowly in the artificial media, and Cyclotella did not grow in the artificial medium without organic supplements. The addition of vitamin B₁₂ to the artificial medium promoted good growth of Cyclotella, and of the species studied this alga was the only auxotroph. Growth in the enriched sea water medium was not affected by a precipitate, but removal of the precipitate markedly affected the rate of growth and the total number of cells obtainable.