The Effect of Salinity Changes Upon the Physiology of Eulittoral Green Macroalgae from Antarctica and Southern Chile: II INTRACELLULAR INORGANIC IONS AND ORGANIC COMPOUNDS

• Published in: Journal of Experimental Botany
• Main Authors: KARSTEN, ULF, WIENCKE, CHRISTIAN, KIRST, GUNTER O.
• Format: Text
• Language: English
• Published: Oxford University Press 1991
• Subjects: Articles; Antarc*; Antarctica
• Online Access: http://jxb.oxfordjournals.org/cgi/content/short/42/12/1533; https://doi.org/10.1093/jxb/42.12.1533

The effects of hypo- and hypersaline treatments ranging from 7–68% on the intracellular inorganic ion and organic solute concentrations were determined in the eulittoral green macroalgae Ulothrix implexa, Ulothrix subflaccida, Enteromorpha bulbosa, Acrosiphonia arcta , and Ulva rigida from Antarctica and Southern Chile. The main inorganic cations were K+, Na+, and Mg2+ in all species. The major osmolyte in E. bulbosa, A. arcta , and U. rigida was K+ at increasing salinities. In both Ulothrix species, however, K+ levels declined during hypersaline stress and Na+ concentrations rose significantly. The main inorganic anions were Cl-, SO2 4- , and PO3 4- in all algae, while E. bulbosa and U. rigida also contained NO+ 3 . A. arcta showed an extremely high SO2- 4 content. The organic solutes proline, sucrose, and β-dimethylsulphoniopropionate (DMSP) played an important role in osmotic acclimation. The occurrence of three organic osmolytes suggests an additional function of these solutes as cryoprotectants in the cold-water macroalgae investigated.