Phytoremediation of iron from red soil of tropical region by using Centella asiatica.

The accumulation and removal efficiency of Fe by Centella asiatica was carried out at various Fe concentrations in soil treatments (0, 50, 100, 150 and 200 mg Fe/kg soil). Iron accumulation in different parts of C. asiatica (leaf, stem and root) was analyzed by atomic absorption spectrophotometer (AAS). Factorial experiment with a completely randomized design and Duncan's test were used for data analyses. The results revealed that C. asiatica have the ability to uptake and accumulate Fe significantly (p < 0.05; r  =  0.977) in the aerial parts. The different soil treatments had significant effect on the total Fe accumulations in C. asiatica (p < 0.05). The potential of C. asiatica as a metal hyperaccumulator plant, harvested for analysis, shows efficient accumulation of Fe at high concentration (p < 0.05; r  =  0.977). The root showed the highest accumulation of Fe followed by the leaves (p < 0.05) and the stem (p < 0.05). The Pearson correlation coefficient between leaves and root have showed highly significant correlation (p < 0.01; r  =  0.785) as compared to the leaves and stem (p < 0.01; r  =  0.780). The efficiency of Fe removal by C. asiatica from the contaminated soil has been evaluated by bioconcentration factor and translocation factor, found to be >1 and <1, respectively, further supporting its metal hyperaccumulator properties.