Exogenous salicylic acid alleviates the accumulation of pesticides and mitigates pesticide-induced oxidative stress in cucumber plants (Cucumis sativus L.)

• Published in: Ecotoxicology and environmental safety Vol. 208; p. 111654
• Main Authors: Liu, Tingting, Li, Tongtong, Zhang, Lingyan, Li, Haolin, Liu, Shangke, Yang, Song, An, Quanshun, Pan, Canping, Zou, Nan
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 15-01-2021; Elsevier
• Subjects: Accumulation; Antioxidants - metabolism; Chlorophyll - metabolism; Cucumber; Cucumis sativus - drug effects; Cucumis sativus - metabolism; Lipid Peroxidation - drug effects; Oxidative stress; Oxidative Stress - drug effects; Pesticides; Pesticides - metabolism; Pesticides - toxicity; Plant Leaves - drug effects; Plant Leaves - metabolism; Proline - metabolism; Reactive Oxygen Species - metabolism; Salicylic acid; Salicylic Acid - pharmacology; Salicylic acid; Oxidative stress; Cucumber; Accumulation; Pesticides
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2020.111654

Salicylic acid (SA) is an important signal molecule, regulating oxidative stress response in plants. In this study, we evaluated the influences of SA (1 mg L−1, 10 mg L−1 and 50 mg L−1) on the accumulation of clothianidin (CLO), dinotefuran (DFN) and difenoconazole (DFZ) (5 mg L−1) and pesticide-induced (CLO-10 mg L−1, DFN-20 mg L−1, and DFZ-10 mg L−1) oxidative stress in cucumber plants. Exogenous SA at 10 mg L−1 significantly reduced the half-lives of three pesticides in nutrient solution and prevented the accumulation of pesticides in roots and leaves. And the role of SA in reducing residues was related to the major accumulation sites of pesticides. By calculating the root concentration factor (RCF) and translocation factor (TF), we found that SA at 10 mg L−1 reduced the ability of roots to absorb pesticides and enhanced the translocation ability from roots to leaves. Roots exposed to high concentrations of three pesticides could reduce biomass, low chlorophyll content, increase the accumulation of reactive oxygen species (ROS) and proline, promote lipid peroxidation, and alter the activities of a range of antioxidant enzymes, respectively. Exogenous SA at low concentrations (1 mg L−1 and 10 mg L−1) significantly mitigated these negative effects. Hence, application of exogenous SA at 10 mg L−1 could effectively alleviate the accumulation of pesticides and induce stress tolerance in cucumber planting systems.
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•Salicylic acid accelerates dissipation of pesticide in nutrient solution.•Salicylic acid blocks the accumulation of pesticide in plants.•Salicylic acid weakens the uptake ability of roots to pesticide in plants.•Low concentration of salicylic acid mitigates oxidative stress caused by pesticide.