Phytoextraction of Pb and Cd; the effect of Urea and EDTA on Cannabis sativa growth under metals stress

Abstract

Contamination of soil with toxic heavy metals is a wide spread environmental problem. Heavy metals adversely affect plant growth, productivity and ultimately human health. A pot experiment was conducted to evaluate the effect of two different concentrations of urea (1500 and 2500 ppm) and single concentration of ethylenediaminetetra acetic acid (EDTA ) (100 ppm) on growth and metal (Pb and Cd) Phytoextraction potential of Cannabis sativa in metals polluted soil. The T2 (Urea 2500 ppm) showed highly significant increase in plant growth and dry biomass, followed by T1 (Urea 1500 ppm) on metals contaminated soil as compared to control (C1). Similarly T4 ( Urea 2500 ppm+ EDTA 100 ppm ) showed higher plant growth, biomass and highly enhanced the uptake of Pb and Cd in different parts of the plant than T3 ( Urea 1500 ppm + EDTA 100 ppm) in metal polluted soil, While T2 (Urea 2500 ppm) alone produced maximum plant growth and biomass than T1 (Urea 1500 ppm) when compared with C1.The application of EDTA alone (T5) (100 ppm EDTA ) increased the Pb and Cd uptake but declined plant growth and biomass which subsequently reduced the total phytoextraction of Pb and Cd. Conclusively,Plant growth and biomass really reduced in metal polluted soil but was increased in metals combination with urea .Addition of EDTA considerably enhanced metals (Pb and Cd) phytoaccumulation.