Work

Exogenous Spermidine Induces Cadmium Stress Tolerance in Cucumber Seedlings by Promoting Plant Growth and Defense System

Year: 2025

Type: article

Abstract: This study aims to investigate the role of exogenous spermidine (Spd) in mitigating the adverse effects of cadmium (Cd) stress on the growth and development of cucumber (Cucumis sativus). The cucumber cultivar “Xintaimici” was used as the experimental material, and a hydroponic experiment was carried out. Based on a baseline Cd concentration of 10 mg·L−1, Spd was supplemented at concentrations of 0.05, 0.1, 0.2, 0.4, and 0.5 mM, resulting in seven treatment groups: control group (CK), S0 group (Cd-only treatment, 10 mg·L−1 Cd + 0 mM Spd), S1+ Cd group (10 mg·L−1 Cd + 0.05 mM Spd), S2+ Cd group (10 mg·L−1 Cd + 0.1 mM Spd), S3+ Cd group (10 mg·L−1 Cd + 0.2 mM Spd), S4+ Cd group (10 mg·L−1 Cd + 0.4 mM Spd), and S5+ Cd group (10 mg·L−1 Cd + 0.5 mM Spd). This study analyzed the regulatory effects of Spd on the growth and development, antioxidant capacity and cadmium accumulation characteristics of cucumber seeds and seedlings. It was found that cadmium stress significantly inhibited their growth process and led to a decline in multiple physiological indicators. Under a Cd concentration of 10 mg·L−1, the application of 0.2 mM Spd significantly improved these parameters. During the seedling stage, the application of 0.2 mM Spd under Cd stress significantly enhanced the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), as well as the content of soluble proteins, while significantly reducing malondialdehyde (MDA) levels. Cd content analysis revealed that 0.2 mM Spd promoted Cd accumulation in roots while suppressing its translocation to young leaves, thereby reducing Cd accumulation in aboveground tissues. Gene expression analysis demonstrated that this treatment significantly upregulated the expression levels of the phytochelatin synthase gene (CsPCS1) and the gene associated with reduced glutathione synthesis (CsGSHS). In conclusion, the exogenous application of 0.2 mM Spd effectively alleviates oxidative damage and osmotic stress induced by Cd stress in cucumber, promotes plant growth, and significantly enhances Cd tolerance.

Source: Toxics

DOI: 10.3390/toxics13100822

Authors: Guangchao Yu, Ming Wei, Zhipeng Wang, Lian Jia, Yue Qu

Institution: Anshan Normal University

Language: English

Topic: Plant Stress Responses and Tolerance

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $3,137