Risk Assessment of some Heavy Metals on Tomato (Solanum lycopersicum L.)

Abstract

In recent decades, serious contamination of soils by heavy metals has been reported, which in turn transmitted to humans through the food chain. It is therefore a matter of urgency to develop a new and efficient technology for removing contaminants from soil. Another aspect to this problem is that environmental pollution decreases the biological quality of soil, which is why pesticides and fertilizers are being used in ever-larger quantities. The environmentally friendly solutions to these problems are phytoremediation, which is a technology that cleanses the soil of heavy metals, a process that helps to protect crops using natural plant compounds. A greenhouse experiment was conducted to determine the effect of some heavy metals such as Zn and Pb (individual and mixture) on Solanum lycopersicum L. (Tomato): on the seed germination, root/shoot growth (plant were grown for 30 days before transferring to experimental pots) and uptake of these metals and determined their concentration in different plant parts by Atomic Absorption Spectrophotometer at the end of this study. The selected metals were dosed at various concentrations ranging from 5, 10, 20 and 50 ppm in addition distilled water for control, to Irrigate plant. Data were statistically analyzed. Result shown that, the seed germination of Solanum lycopersicum L. (Tomato) was found significantly affected by these metals, where it was decreased with increase of concentration this heavy metals. Root and shoot growth of Solanum lycopersicum L. (Tomato) were found not significantly affected by these metals, concentration of both Zn and Pb in different parts of plant increased with increase the concentration of these metals in treatments, where Zn concentration was: Shoot > Root >Fruit but Pb concentration was: Root > Shoot > Fruit.