In plants, excess selenium causes general toxic symptoms. However, salicylic acid plays an important role in alleviating toxic effects of various stresses. This study aimed to clarify the role of exogenous foliar salicylic acid on alleviating selenium toxicity of pak choi exposed to moderately and highly Se-excessive soils (4 mg·kg⁻¹ Se and 10 mg·kg⁻¹ Se, respectively). The results showed that Se stress caused severe lipid peroxidation, desynchronization of the antioxidant enzymatic system, and significant decreases in the measures of photosynthetic activity and shoot biomass. Under Se stress conditions, exogenous foliar salicylic acid significantly increased measures of photosynthetic activity and shoot biomass, increased catalase activity, and decreased measures of oxidative stress. Moreover, exogenous salicylic acid significantly enhanced Se accumulation in shoots under Se stress conditions. We demonstrate here that foliar spraying with salicylic acid is an effective measure to alleviate the adverse effects of Se stress and enhance Se accumulation for optimizing crop Se biofortification in Se-excessive soil.

在植物中，过量的硒会导致一般的中毒症状。然而，水杨酸在减轻各种压力的毒性作用方面起着重要作用。本研究旨在阐明外源叶面水杨酸对减轻白菜在中度和高度硒过量土壤（4 mg·kg ^-1 Se和10 mg·kg ^-1Se，分别）。结果表明，硒胁迫导致严重的脂质过氧化、抗氧化酶系统的不同步以及光合活性和枝条生物量的显着降低。在硒胁迫条件下，外源叶水杨酸显着增加了光合活性和枝条生物量的测量值，增加了过氧化氢酶活性，并降低了氧化应激的测量值。此外，外源水杨酸在硒胁迫条件下显着增强了芽中硒的积累。我们在这里证明，叶面喷洒水杨酸是减轻硒胁迫的不利影响和增强硒积累以优化硒过量土壤中作物硒生物强化的有效措施。