Effect of Salicylic Acid on Antioxidant Enzymes and Cold Tolerance of Cucumber Plants

The effect of salicylic acid (SA) on the reaction of cucumber plants (Cucumis sativus L.) on the effect of low positive temperatures has been studied. It was found that treatment with SA promotes a decrease in the release of electrolytes from the tissues of cotyledonous leaves of seedlings exposed to subdamaging (12°C) and damaging (4°C) temperatures. In the leaves of seedlings treated with SA and exposed to cold, a higher activity of superoxide dismutase, catalase, and guaiacol-specific peroxidase was recorded as well as an increase in the accumulation of transcripts of the genes encoding them (CuZnSOD and CAT) compared to the control variant (without SA treatment). Under the action of low temperatures (12 and 4°C) on seedlings, SA also reduced the formation of one of the end products of lipid peroxidation, malondialdehyde, in seedling leaves. It was concluded that SA has a protective effect on cucumber seedlings when exposed to low positive temperatures, which is expressed in the activation of antioxidant enzymes and a decrease in the level of oxidative stress.