Phytoremediation of heavy metals (lead and zinc) by three plant species; grass pea (Lathyrus sativus),

This study was carried out to analyze the amount of heavy metals uptake by three agricultural plants (grass pea, Vetch flower cluster, Alfalfa) and compare these three species with each other at the research greenhouse of the College of Agriculture, Islamic Azad University, Karaj Branch. Factorial experiment with a completely randomized design was used for data analysis, and the Duncan’s approach was used for mean comparison. The analyses showed that as lead and zinc increased the amount of all contaminants in the root and shoot of plants increased significantly. Also, alfalfa is the most capable in absorption of the elements. The sample was taken from the agricultural contaminated soil of the land near the zinc concentrate factory and lead and zinc mines located 10 kilometers out of Zanjan Province. The examined plants had a relatively better capability in storing elements in their shoots than in their roots. Measuring transfer factor (TF) revealed that vetch had a higher capability than the other two in transferring lead from root to shoot, and species of vetch and alfalfa had higher capabilities in root-to-shoot transfer of zinc than grass pea. Mycorrhiza increases uptake of heavy metals from soil. This happens when there is a high amount of heavy metals in the soil.