Assessment of phytoremediation capacity of three halophytes: Suaeda monoica, Tamarix indica and Cressa critica.

Halophyte is a distinctive group of plants that can survive, even well flourish, at a concentration of Na+ and Cl- ions along with heavy metals that would be lethal to most of the agricultural crop species. These capabilities make certain halophytes good contenders for phytoremediation through phytoextraction or phytostabilization of the salt and heavy metals (HMs) in polluted soils. Thus, the present study elucidates the phytoextraction capacity of three halophytes (Suaeda monoica, Tamarix indica and Cressa critica) growing in saline soil (EC 112 ds m-1), with higher level of HMs rather than a cultivated soil. The accumulation of ions in above-ground tissue was determined in the all three studied plants, considering the fact that maintaining a stable cytosolic Na+/K+ ratio has become a crucial salinity tolerance mechanism. The higher salinity of soil resulted in high level of Na+ ions in leaves, increased synthesis of osmolyte components and robust antioxidant activities to combat the oxidative stress. As whole, changes in cellular metabolites were determined by using FT-IR spectroscopy, evident as differential FT-IR profiles in both leaves and stem specific to these metabolites. The considerable amounts of HMs accumulation including Zn, Fe, Mn, Cu, Cr, and Cd with highest being Fe in above-ground tissue of all three studied halophytes were obtained. These preliminary findings represent S. monoica, T. indica and C. cretica as potent phytoremediation plant using phytosequestration to accumulate HMs. The present study project a light on the use of these three plants in reclamation of degraded saline soils.