Seasonal Changes in the Antioxidant System in the Leaves of the Ornamental Tree Paulownia Tomentosa Introduced for Urban Landscaping in Tashkent

At present, one of the fundamental problems is the study of cellular and molecular mechanisms of plant adaptation to adverse environmental conditions. The formation of an adaptive response to abiotic stressors in a plant organism occurs as a result of many metabolic changes. It is known that all living organisms have the ability to adapt to biotic and abiotic environmental factors and protect themselves from adverse conditions. The article provides information on the state of the antioxidant system of Paulownia, an ornamental plant growing in Tashkent, from June to September. The studies were carried out for 5 years and studied the activity of antioxidant enzymes in paulownia leaves - catalase and SOD, as well as the amount of free proline and malondialdehyde. In addition to the impact of environmental factors, the anthropogenic impact in the form of additional roads was also studied. In July, in the leaves of Paulownia tomentosa growing in the Botanical Garden, a sharp decrease in the content of malondialdehyde was observed, at this time catalase activation was observed, and by August also SOD activation. In connection with the activation of lipid peroxidation in the highway, it can be seen that the amount of proline also has high values during the season, which in turn controls the formation of reactive oxygen species.