Investigating the effect of heavy metals like lead and cadmium on absorption of high consumption nutrients in (Glycyrrhiza glabra)

 Toxicity of heavy metals and their accumulation in soil, plant and food chains is one of the main environmental and health problems of today's societies. In this regard, the impact of these metals on valuable medicinal plants and forages that enter into the food chain through human and animal consumption is of particular importance. Glycyrrhiza glabra L. is one of the most valuable species which is important in the world due to the presence of important medicinal and nutritional compounds in its roots and rhizomes and has been considered by the pharmaceutical and food industries. The purpose of this study is to investigate the effect of heavy metals of lead and cadmium on the absorption of high consumption nutrients and also the accumulation of these elements in the tissues of the lichen plant.

  This research was carried out in a completely randomized design with two treatments of lead and cadmium in 4 replicates and 6 concentrations in pot culture (a total of 48 pots). The treatments consisted of concentrations of 0, 10, 20, 40, 80 and 160 (ppm) for cadmium and zero, 50, 100, 200, 400 and 800 (ppm) for lead. After preparing bedding and spraying a heavy metal salts solution of lead and cadmium with the above concentrations, rhizomes were cultivated in pots and placed in the greenhouse for 7 months under irrigation and care. Finally, samples of soil and plant (in two parts of the air and underground organs) were prepared and transferred to the laboratory for acid digestion and extraction of lead and cadmium. To assess the plant's ability, TF, BCF and BAC indices were also used to evaluate the accumulation capacity of these elements.

  The results of the comparison of the mean of lead and cadmium in the studied concentrations showed that increasing the concentration of these two elements in the soil did not have a significant effect on the amount of potassium, sodium, magnesium, calcium and organic matter in the aerial and underground parts of this plant. While the increase in the concentration of cadmium in the soil has a significant reducing effect on the amount of this metal in the air and underground organs and the amount of nitrogen in the air. Also, the increase in lead concentration has a significant effect on the amount of this metal in the air and underground organs and the amount of phosphorus and nitrogen in the air.

 The results of the study on the accumulation and transfer of cadmium and lead in the lichen plant showed that the plant could play the role of stabilizing plant and extractive plant in these two heavy metals, respectively