Subcellular adaptation to salinity and irradiance in Dunaliella salina

Abstract

Dunaliella salina V-63 was cultivated in different concentrations of NaCl (0.5, 1.0, 2.5, 3.0, or 4.0 M) and at two irradiances (170 or 220 umol m -2s-1). Concentration-dependent suppression of growth was observed above 1 M NaCl, and elevated salinity induced formation of salt-containing vacuoles. However, the changes in the chloroplast ultrastructure following changes in salinity and irradiance (increase of invaginations and protuberances, numerous grana with low number of thylakoids, less number of starch grains, etc.) appeared to be of primary importance.