Effect of salinity on ion content, plant pigments, soluble sugars and starch of halophyte plant (Aeluropus littoralis)

In this research some of physiological parameters and ion uptake and accumulation of halophyte plant Aeluropus littoralis were investigated. Experiment design was randomized complete block design in greenhouse condition in Genetics and Agricultural Biotechnology Institute of Tabarestan, Sari Agricultural Sciences and Natural Resources Universitywith with five salt levels (0, 20, 40, 60 and 80 dS/m) and three replicates in 2010. Some parameters such as plant pigments٫ soluble sugar concentrations and starch and sodium and potassium content in three parts of plant (leaves, stems and roots) were determined. Results indicated that increasing of salinity significantly decreased chlorophyll a٫ b٫ a+b and carotenoeids content. Starch amount increased up to 20 dS/m and then markedly declined. By contrast٫ soluble sugars decreased up to 20 dS/m and then significantly increased. Salinity also significantly affected sodium and potassium content in plant organs so that with increasing salinity, sodium content significantly increased but potassium content declined. Results also showed that in high levels of salinity, sodium concentrations in roots are more than shoots. Under salt stress, sodium might returns from aerial organs to roots or maybe it is because of limiting transfer of sodium from roots to shoots and save it in roots as a mechanism of salt resistance. These results showed that Aeluropus littoralis as a halophyte plant could resistants salinity up to 20 dS/m and then with increasing salt stress, starch was broken down and produce soluble sugars to help osmotic adjustment to tolerate against salinity.