Effect of NaCl, copper and cadmium ions on halophytes with different types of salt resistance: accumulation, physiological and biochemical reactions

The capacities of the euhalophyte SaLi-Cornia perennans Willd. and glycohalophyte Artemisia santonica L. to accumulate NaCl, Cu, and Cd, as well as their physiological and biochemical responses to these compounds, was investigated. Seeds were germinated in distilled water for 1-3 days and then sown in containers with sand. Plants were watered with Robinson's nutrient solution. After 3 months, plants were divided into two groups: experimental and control. In the experimental group, soil was treated with 1M NaCl, 10 mM Cu(NO3)2, and 10 mM Cd(NO3)2 for 24 h. The exposure to high concentration of NaCl in the experiment did not affect the baseline level of Na, which was twice as high in S. perennans as in A. santonica. Plant exposure to Cu and Cd caused their accumulation in the aboveground parts of both species. The accumulation capacity of the euhalophyte was many times higher than that of the glycohalophyte. We analysed functional parameters of leaves by measuring photosynthetic pigments, structural parameters of membranes by assessing the lipid profile, and the balance of pro/antioxidant processes. Using data on changes in several biochemical parameters, the sensitivity of the two different halophytes to metal ions was as follows: for S. perennans - Cu > Na > Cd; for A. santonica - Na > Cu > Cd. Our findings suggest that S. perennans can be used for heavy metal extraction from soil in phytoremediation, whereas A. santonica will be more effective for greening of polluted territories.