Phytoremediation of fluoride with garden ornamentals Nerium oleander, Portulaca oleracea, and Pogonatherum crinitum

Nursery grown plants of Nerium oleander , Pogonatherum crinitum , and Portulaca oleracea were observed to remove fluoride up to 92, 80, and 73%, respectively, from NaF solution at the concentration of 10 mg L −1 within 15 days. Concentration range of 10–50 mg L −1 of fluoride revealed a constant decrease of removal from 92 to 51% within 15 days by N. oleander , while the biomass (one to five plants) showed enhancement in removal from 74 to 98% in 10 days. Translocation and bioaccumulation factors calculated after fluoride contents in roots and leaves of N. oleander , P. crinitum , and P. oleracea were 1.85, 1.19, and 1.43, and 9.8, 3.6, and 2.2, respectively. P . oleracea , P. crinitum , and N. oleander showed reductions in chlorophyll contents by 40, 57 and 25 and 8%, carbohydrates by 50, 44, and 16%, and proteins by 38, 53, and 15%, respectively. Activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) in the roots of P. oleracea , P. crinitum , and N. oleander were observed to be induced by 400, 383, and 500%; 80, 105, and 424%; and 153, 77, and 71%, respectively, while the leaves showed induction in SOD, CAT, and GPX activities by 550, 315, and 165%; 196, 227, and 243%; and 280, 242, and 184%, respectively. Results endorsed the superiority of N. oleander for fluoride removal over other plant species.