Document Type : Research Paper
Department of Biology, Faculty of Science , Payame Noor University, Tehran, Iran
Department of Biology, Faculty of Science and Technology, University of Isfahan, Isfahan , Iran
Lead is one of the most abundant and toxic heavy metals which can have lethal effects on plants. The Pb contamination be generated by mining, industrial, activities and fossil fuel burning. Some metallophytes plants which belongs to Brassicaceae family are able to grow in soils contaminated with heavy metals. The purpose of this study is to evaluate the resistance and lead accumulation of the metallicolous species Matthiola flavida collected from the vicinity of the Irankouh Pb/Zn mine in Isfahan, Iran, which is compared with its non- metallicolous species Matthiola incana to used Pb phytoremediation. Non-metallicolous (Matthiola incana) and metallicolous plants (Matthiola flavida) were transferred to hydroponic mediums and after proper vegetative growth, they were exposed to 0, 10, 50, 100, 150 mg/L treatments of lead for 14 days. The results showed that with the increasing lead concentration, the growth of both species significantly decreased, but this reduction in growth was always greater in the non-metallicolous species, so that at the highest stress level, the dry weight of shoots and roots decreased in the metallicolous to %7.1 and % 28.8, but in the non-metallicolous to %69.9 and %60.8 in comparison with their control respectively. With the increasing the concentration of Pb in the medium, the accumulation of lead in the roots of both species enhanced, but Pb concentration roots and translocation factor of the metallicolous species compared to the non-metallicolous species was more than 4-folds at the lowest stress level, which decreased with the increasing lead concentration. Then, the compatible mechanisms of the metallicolous species are the ability to control the transfer of lead to the shoot in different concentrations, which makes it suitable for growing in lead-contaminated areas.