Fitoremediation method and removal of lead accumulation: Example of rosemary (Rosmarinus officinalis)

Heavy metals are among the most important factors causing soil pollution and have toxic effects even at very low doses. Heavy metal pollution has increased rapidly since the industrial revolution. Today, metal pollution is cleaned by using plant material with the green breeding method. In addition, the phytoremediation technique does not harm natural resources. The aim of this study was to remove lead (Pb) heavy metal accumulated in contaminated soils by using phytoremediation method with Rosemary (Rosmarinus officinalis) plant and to determine the hyperacumulator capacity of this plant. The research was carried out in Tekirdağ Namık Kemal University Agriculturel Faculty Soil Science and Plant Nutrition Laboratory. It was carried out using 5 different doses of Pb pollutant and control pots in 3 repetitions according to the "Complete Blocks Based on Chance" trial design. Pb doses applied as a contaminant were given as 10 mgkg-1, 20 mgkg-1, 40 mgkg-1, 80 mgkg-1, 100 mgkg-1 Pb (PbNO3). EDTA chelator (10 mmol/kg) was applied to the pots with contaminants. Then, the pollutant parameter was kept in the soil under natural conditions for 30 days. It was planted with 3 plants in each pot. The plants were harvested at the end of a two-months growth period and the measurements of the plant in each pot were made, and the plant samples were grinded and Pb heavy metal analysis and N, P, K, Ca, Mg, Fe, Cu, Zn, Mn nutrient element were made. In addition, the necessary physical and chemical analyzes of the trial soil were made. As a result of this study, the plant wet weight of rosemary plant in pots with different doses of lead was 26,3 g in pots with a dose of 100 mgkg-1, the dry weight of the plant was 8,6 g at a dose of 100 mgkg-1, the root wet weight was 17,6 g at a dose of 100 mgkg-1. dry weight was determined as 6,6 at a dose of 100 mgkg-1. While the plant height, root length, and branch number decreased in pots where the highest lead doses of rosemary plant were applied, the changes in SPAD values were not found to be statistically significant. The lead values were determined as 2,25 mgkg-1 in the stem and 24,85 mgkg-1 in the root in pots with the highest dose (100 mgkg-1) applied to the rosmarinus (Rosmarinus officinalis) plant. The use of medicinal and aromatic plants to clean the pollution in soils contaminated with heavy metals has produced positive results in terms of economy and without harming the nature. It is an important option, especially in terms of its easy applicability.