Ecology and taxonomy of yeasts isolated from various marine substrates

Yeasts wcrc observed to be of common occurrence in subtropical marine waters and scdimcnts and with indwelling plants and anilnals. The most prevalent types prcscnt in all environments were oxidative, asporogcnous forms which expressed a growth requircmcnt for one or more vitamins. Certain distinctive metabolic attributes of yeasts were associated with environmental distribution. The incidental yeast flora on marine vegetation was uni-formly low in number and consistent with the spccics isolated from surrounding waters and scdimcnts. The species found within the intestinal contents of fish appcarcd to be of transitory nature and restricted in population density. Yeasts have been found in significant numbers in the waters of those oceans and seas that have been systematically studied. The enumeration and taxonomy of yeasts in Atlantic subtropical marine waters and sedi-ments has been reported by Fell, et nl. ( 1960) wherein the influence of terrestrial run-off on the yeast populations of estuarine areas and the presence of yeasts in plank-tonic masses and benthic sediments was established. As a further and continuing study of the ecology and systcmaties of marine fungi, selected aquatic habitats were examined intensively for the occurrence of yeasts to establish possible sites of active growth and reproduction of these micro-organisms. In this work, quantitative and qualitative studies of the indigenous yeast flora isolated from diverse marine waters, sediments, and associated plants and ani-mals were undertaken