EDTA enhances lead uptake and facilitates phytoremediation by vetiver grass

Vetiver grass (Vetiveria zizanioides) has strong and dense root system and is a potential phytoremediator plant since it can tolerate a wide range of climatic conditions and grow well in soils contaminated with heavy metals. Soil was artificially contaminated by lead (20 mgl(-1)) during field trials. Four concentration of EDTA (Ethylene diamine tetra acetic acid-disodium salt) solution i.e. 0, 3, 5 and 10 mmol kg(-1) were added to soil prior to harvesting, to study the influence of EDTA solution on phytostabilization by vetiver grass. Results showed that the concentration of lead in roots of vetiver is significantly increased after EDTA solution (5 mmol kg(-1)) application. However, high concentration of EDTA (10 mmol kg(-1)) does not show such significant increase. The toxicity of highly contaminating metal did not affect the growth of vetiver grass significantly but a slight decrease in parameters studied was noticed. No stress symptoms were observed in vetiver plants. Results of present study reveal that vetiver could be considered as a potential phytoremediator for lead contamninated site.