EFFECTS OF NUTRIENTS AT DIFFERENT SALINITIES ON GROWTH OF THE FRESH-WATER GREEN-ALGA SCENEDESMUS-BIJUGATUS IN WATER OF NARENDRA POND, PURI,ORISSA

The growth and biochemical composition of Scenedesmus bijugatus grown in normal and nutrient enriched Narendra Pond water was evaluated at d ifferent levels of salinity. In normal pond water (NPW) the growth was enhanced when the initial salinity of the water was doubled (to 7.2 m mol/l) but further salinity increase caused growth retardation. In nut rient enriched pond water (NEW), however, the maximum growth occurred in the culture containing 29 mmol/l of NaCl. At growth retarding salt concentrations the chlorophyll, carbohydrate, protein and lipid conten ts per cell decreased in both NPW and NEW while the proline content fi rst increased and was then reduced. All nutrients, taken separately or in combination, caused growth enhancement of the alga ar the three se lected salinity levels. The alga showed a better halotolerance when en riched with nitrogen or phosphorus.