Effect of indole-3-acetic acid, kinetin, and ethylenediaminetetraacetic acid on plant growth and uptake and translocation of lead, micronutrients, and macronutrients in alfalfa plants
International Journal of Phytoremediation
Alfalfa plants germinated and grown for 15 d in soil containing 80 mg Pb kg-1 were treated with ethylenediaminetetraacetic acid (EDTA) at 0.8 mM and indole-3-acetic acid-kinetin (IAA-KN) at 100 μM. Fifteen days after the treatment application, the concentration of lead (Pb), macronutrients, and micronutrients was determined using inductively coupled plasma/optical emission spectroscopy. The chlorophyll content and plant growth were also measured. Roots of plants exposed to Pb alone, Pb-EDTA, and Pb-EDTA-IAA-KN had 160, 140, and 150 mg Pb kg-1 DW, respectively. Pb was not detected in the stems of plants exposed to Pb alone; however, stems of plants treated with EDTA and EDTA-IAA-KN had 78 and 142 mg Pb kg-1 DW, respectively. While the Pb concentration in leaves of plants treated with EDTA and EDTA-IAA-KN was 92 and 127 mg kg-1 DW, respectively. In addition, EDTA and EDTA-IAA-KN significantly increased the translocation of zinc and manganese to leaves. The x-ray absorption spectroscopic studies demonstrated that Pb(II) was transported from roots to leaves without a change in the oxidation state. Copyright © Taylor & Francis Group, LLC.