Phytoremediation of cadmium and nickel using Vetiveria zizanioides

Phytoremediation is a well known heavy metals remediation technique for contaminated soils and water. The present study was aimed to evaluate the uptake and dry weight response of vetiver grass (Vetiveria zizanioides L.) subjected to different levels of cadmium (Cd) (0, 3, 6 and 12 mg/kg soil) and nickel (Ni) (0, 50, 100 and 200 mg/kg soil) stress. The experiment was conducted in pots using a completely randomized design with four replications for three months. Concentration of Ni and Cd was determined using atomic absorption spectrophotometer. The dried weight of aerial and underground parts of Vetiver grass individuals at the end of the experiment were used to compare plant weight response to different stresses. Statistical analysis was performed using version 18 of SPSS software and analysis of variance (ANOVA) and mean comparisons were completed through Tukey method. No restrictions on Cd uptake was observed in root and shoot of Vetiver grass, but in the case of Ni, its concentration in shoots of vetiver grass decreased with higher metal levels.The highest transfer factor (TF) among Ni treatments was observed at the lowest concentration (50 mg/L) and the highest TF among Cd treatments was observed at the highest concentration (12 mg/L). Results revealed that Ni and Cd had a significant (p 0.05) positive effect on shoot and root dry weight of Vetiver grass. Our results suggest capability of this plant for use in phytoextraction of Ni and phytostabilisation of Cd contaminated soils.