Аннотация:Hypoxia is one of the common abiotic stresses that negatively affects the development andproductivity of agricultural crops. Quercetin is used to protect plants from oxidative stress whenexposed to environmental stressors. O2 deficiency leads to impaired development and morphometricparameters in wheat varieties Orenburgskaya 22 (Triticum aestivum L.) and varieties Zolotaya (Triticumdurum Desf.). Cytological analysis revealed various types of changes in the cytoplasm under conditionsof hypoxia and treatment with quercetin. The most critical changes in the cytoplasm occur in theZolotaya variety during pretreatment with quercetin followed by hypoxia, and in the Orenburgskaya22 variety during hypoxia. Quercetin has a protective effect only on the Orenburgskaya 22 variety,and also promotes a more effective recovery after exposure to low O2 content. Hypoxia causes anincrease in reactive oxygen species and activates the antioxidant system. It has been shown that themost active components of the antioxidant system in the Orenburgskaya 22 variety are MnSOD andCu/ZnSOD, and in the Zolotaya variety GSH.We have shown that quercetin provides resistance onlyto the wheat genotype Orenburgskaya 22, as a protective agent against abiotic stress, which indicatesthe need for a comprehensive study of the effects of exogenous protectors before use in agriculture.