PHYTO-REMEDIATION OF LEAD-CONTAMINATED SOIL USING AMARANTHUS CRUENTUS

Previous studies have shown that some vegetables have the ability to absorb metals from soil. Since they are early maturity species, they possess the potential to be used as phytoremediating agents. Also, synthetic chelates have been found to induce lead desorption from soil matrix, thereby enhancing uptake into plant tissues. Therefore, a study was carried out to determine the potential of Amaranthus cruentus as a soil lead remediating plant. The experiment was carried out using a randomized block design. Soil samples were subjected to five levels of lead contamination namely control, 600ppm, 600ppm + EDTA, 1800ppm and 1800ppm + EDTA, each treatment had five replicates. Three plants each were carefully transplanted from nursery to experimental pots and grown for 32 days. Ethylenediaminetetra acetic(EDTA) (3.0 mmole EDTA/kg soil) was applied to EDTA amended treatment 8 days before harvesting. The result showed that EDTA has some effect on lead solubility in soil as well as lead absorption by A.cruentus. However, there were variable increases in lead uptake from the contaminated soil to the plants. Lead contamination did not have significant effect on growth and yield parameters of A cruentus. Since the transfer factor (TF) of the plant is greater than one, it may be a promising species for phytoremediation.