Today, the resistance of plants to stress is one of the most basic and important problems. Plants are sufficiently resistant to oxidative disorders that occur with sudden changes in the physiological state of the organism. This suggests that plant cells have an antioxidant system that can protect against oxygen radicals and singlet oxygen. They are different from animals that have an immune system. The article describes the state of the antioxidant system of the Platanus orientalis tree in the urban semiarid zone from June to September. In addition to the impact of climatic conditions, the impact of an additional man-made stress factor in the form of a highway was also assessed. 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 describes the state of the antioxidant system of the plane tree plant growing in Uzbekistan in the summer. During the season, the amount of malondialdehyde and proline was studied.

Proline, malondialdehyde, antioxidant system, stress-resistant plants, an active form of oxygen

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