Effect of biodegradable chelant nitrilotriacetic acid on lead (pb) phytoextraction efficiency of coronopus didymus grown in pb-contaminated soil

Abstract

The current study investigated the use of nitrilotriacetic acid (NTA), a biodegradable chelating agent, on the phytoextraction of lead (Pb) from soil using Coronopus didymus. The plants were exposed to three different Pb concentrations: 3500, 4500, and 5500 mg kg-1 alone and in combination with 10 mM kg-1 of NTA. The morphological traits such as plant growth and biomass, the Bioconcentration Factor (BCF) values, and Pb accumulation in roots, stems, and leaves were measured. The plant growth and dry biomass were found to be maximum at 3500 mg kg-1 Pb and minimum at 5500 mg kg-1 Pb as compared to the control under Pb alone treatments and in combination with NTA. The supplementation of NTA significantly enhanced the Pb accumulation in different plant parts and was in the order: roots > stems > leaves. Compared to the BCF values of stems and leaves, the BCFroots values, which ranged from 89.3 to 257, were highest for all the treatments. NTA application resulted in the highest BCF value at 3500 mg kg−1 Pb concentration in roots. The present study suggests that the use of NTA as a chelating agent significantly increased the ability of C. didymus plants to remove Pb from the environment. This approach can be widely used for efficient remediation of contaminants from the metal-contaminated soils.