摘要：Disturbance of natural ecosystems is assumed serious purpose and in the region of central Kosovo, particularly in the industrial areas of lead and zinc mining in the Kisnica mine and the thermal power plant, Obilic. Deposits of tailings from these industrial zones near the villages Gracanica and Plemetina have led to pollution of the soil and river water flows of the area and surrounding regions. Residents who live in the outskirts of these villages use domestic wells for water supply and eat homegrown food, especially early vegetable crops from their small gardens. In stress conditions, such as heavy metal toxicity and fly ash pollutants, an increase in antioxidant enzyme activities are important for plants to tolerate the stress. The antioxidant defense system in plant cells is composed of an enzymatic defense, such as catalase (CAT), and a non-enzymatic defense such as organic acids. Although the seeds are tolerant to the presence of all metals, the percentage of germinated seeds depends on the concentration and type of heavy metal, and the seed species. Lettuce seeds sown in the acidic soil (pH 2.74) from Kisnica with very high concentrations of Cr, Ni, Pb, Al and Fe were completely inhibited at the germination stage. An increased catalase activity in different organs of plants under conditions of environmental pollution is a mechanism of detoxification and of acquiring stress resistance. Catalase activity in radish and lettuce, particularly in the early development stage (7 and 14 days) was measured in seedlings of soil substrate from Plemetina, which is dominated by sulfur pollutants. The highest content of organic acids in the above-ground organs was observed in plants of radishes grown in soil originating from Gracanica, with a several-fold increase compared to control. Taken together, the increased catalase activity and organic acid content in the radish and lettuce plants grown in soil heavy with deposits of tailings is most likely a plant defense mechanism to toxicants.
