Evaluation of biochemical and physiological responses of salsola spp at their natural habitats

Abstract

Halophytes are naturally salt-tolerant plants that are useful for soil remediation applications. Biochemical and physiological responses of Salsola species, namely; S. ruthenica, S. dendroides and S. crassa were evaluated at their natural habitats for their salt tolerance in which the biochemical responses such as peroxidase (POX, EC.1.11.1.7) and catalase (CAT, EC.1.11.1.6) enzymes, inorganic ion accumulation, proline (Pro), malondialdehyde (MDA), chlorophyll contents (Chl-a, Chl-b) were measured. The results showed that variation existed in Salsola spp. in their response to salinity. Although all Salsola spp. showed similar trends, S. ruthenica expressed higher activities of antioxidant enzymes along with the higher accumulation of proline, MDA contents than those of S. dendroides and S. crassa spp. Leaves of all three species exhibited high Na+ content while K+, Ca++ and Mg++ contents are low. S. ruthenica accumulated 94.5 g kg-1 DW of Na+ ions while S. dendroides and S. crassa accumulated 82.1 g kg-1 DW and 71.4 g kg-1 DW Na+ ions, respectively. The increase in enzymatic activities and higher metabolic contents and lower MDA levels in Salsola spp., especially in S. ruthenica, suggested that these species could well be used for phytoremediation purposes. With moderate height and root-length, these plants have high potentials to be used as companion plants with glycophytes to reduce salt stress in moderately saline conditions.