Phytoremediation potential of some halophytic species for soil salinity

ABSTRACT

Phytoremediation potential of six halophytic species i.e. Suaeda nudiflora, Suaeda fruticosa, Portulaca oleracea, Atriplex lentiformis, Parkinsonia aculeata and Xanthium strumarium was assessed under screen house conditions. Plants were raised at 8.0, 12.0, 16.0, and 20.0 dSm⁻¹ of chloride-dominated salinity. The control plants were irrigated with canal water. Sampling was done at vegetative stage (60–75 DAS). About 95 percent seed germination occurred up to 12 dSm⁻¹ and thereafter declined slightly. Mean plant height and dry weight plant⁻¹ were significantly decreased from 48.71 to 32.44 cm and from 1.73 to 0.61g plant⁻¹ respectively upon salinization. Na⁺/K⁺ ratio (0.87 to 2.72), Na⁺/ Ca²⁺ + Mg²⁺ (0.48 to 1.54) and Cl⁻/SO₄^2– (0.94 to 5.04) ratio showed increasing trend. Salinity susceptibility index was found minimum in Suaeda fruticosa (0.72) and maximum in Parkinsonia aculeata (1.17). Total ionic content also declined and magnitude of decline varied from 8.51 to 18.91% at 8 dSm⁻¹ and 1.85 to 7.12% at 20 dSm⁻¹ of salinity. On the basis of phytoremediation potential Suaeda fruticosa (1170.02 mg plant⁻¹), Atriplex lentiformis (777.87 mg plant⁻¹) were the best salt hyperaccumulator plants whereas Xanthium strumarium (349.61 mg plant⁻¹) and Parkinsonia aculeata (310.59 mg plant⁻¹) were the least hyperaccumulator plants.

KEYWORDS:

• phytoremediation potential
• phytoextraction
• salt hyperaccumulator
• salt tolerance
• salinity

Acknowledgment

The receipt of research grant from University Grants Commission (UGC), New Delhi, under the project of Post Doctoral Fellowship for Woman entitled “Physiological and Molecular characterization of some salinity phytoremediating species” is gratefully acknowledged.