Phytoextraction of cadmium and lead by three vegetable-crop plants

Abstract

Phytoextraction, is an effective and promising means to cure soil contamination with heavy metals. The present study investigates the ability of three vegetables plants for removal of heavy metals from the contaminated soil and metal mobilization to different plant parts. The three plants selected for the study, Momordica charantia, Vigna unguiculata and Solanum melongena were grown for 90 days in soils artificially contaminated with cadmium (Cd) and lead (Pb) (50mg metal/kg of soil). The concentrations of the two metals were observed to be higher in roots of M. charantia and V. unguiculata than in soil, but root Pb level of S. melongena was slightly lower than that of soil after 90 days. Translocation potential of the heavy metals indicated higher accumulation of Cd in roots of M. charantia and S. melongena than in leaves while the pattern was completely opposite in V. unguiculata.  Lead accumulation was higher in roots than in leaves for all the three plant species studied. The Translocation Factor (TF) of Cd for the three plants was in the range of 1.16 to 2.29 whereas, TF values of Pb remained <1, indicating that only small amount of Pb was translocated from roots to aerial parts.