Abstract :
ABSTRACT: Influence of phosphorus (P) levels and ethylene diamine tetra acetic acid (EDTA) addition on lead (Pb) phytoremediation by maize was investigated in a greenhouse experiment on a Pb-polluted calcareous soil. Results showed that EDTA addition increased Pb concentration and uptake in maize root and shoot in all P levels. Addition of P levels, however, decreased Pb concentration in maize root and both Pb concentration and uptake in maize shoot in the presence or absence of EDTA. In all P levels, Pb uptake and Pb phytoextraction efficiencies were higher in maize grown on EDTA-treated soil as compared to the EDTA-untreated soil. Addition of P levels, however, decreased the amount of Pb uptake efficiency and Pb phytoextraction efficiency. Addition of EDTA, however, drastically decreased Pb translocation efficiency. Decrease in the Pb translocation efficiency in maize grown on EDTA-treated soil was attributed to higher increase in Pb uptake in maize roots as compared to maize shoots following EDTA addition. The addition of EDTA increased the Pb remediation factor, the percentage of Pb removed by maize shoot from the total Pb content in the soil. The percentage of Pb removed by maize shoot from the total Pb content of the studied polluted soil was, however, lower than the extent which is desired for the remediation of such soils.
