Chloroplast Implication in the Tolerance to Salinity of the Halophyte Cakile maritima

Abstract

In this study, the response of the chloroplastic antioxidant system of the halophyte Cakile maritima Scop. and its tolerance to NaCl stress have been studied using purified chloroplasts. Seedlings were grown in different salt concentrations (0, 100, 200 and 400 mmol/L NaCl) and plants were harvested after 40 days. Isolated chloroplasts were purified by centrifugation in density-gradients of Percoll. The evaluation of the oxidative stress was analysed measuring lipid peroxidation, carbonyl protein, $${\text{O}}_{2}^{ - }$$ and H2O2 contents and the antioxidant status by measurement of the activities of superoxide dismutase, catalase, peroxidase and enzymes of the ascorbate–glutathione cycle as well as the antioxidants ascorbate and glutathione, in the purified chloroplasts. Results revealed that the best growth response of C. maritima under moderate salt stress was associated with a low oxidative stress, the highest activities of SOD, POD and APX and the highest glutathione content. The interaction between the water status of the plant and mineral nutrition seems to be strongly involved in the plant performance under salinity.