Yan Guochao, Zhao Shuaijing, Dong Jiaqi, Qiu Haiying, Li Baoyu, Cao Long, Yuan Tiantian, Zhu Xuyongjie, Mao Shengming, Wang Peiwen, Xu Yunmin, He Yong, Liang Yongchao, Zhu Zhujun
Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable of Ministry of Agriculture and Rural Affairs, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, Zhejiang, China.
Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China.
Plant Physiol Biochem. 2025 Jun 13;227:110156. doi: 10.1016/j.plaphy.2025.110156.
Salt stress induces potassium (K) leakage and deficiency, thereby limiting plant growth. The decrement of K leakage (also called K retention) plays a key role in plant salt tolerance. Silicon (Si) can alleviate salt stress and promote K nutrition status in plants, however the mechanisms behind remain unclear. In this study, the regulatory effects and related mechanisms of Si on root K retention in cucumber were investigated. The results showed that salt stress induced significant growth inhibition, Na accumulation and K deficiency in cucumber, while Si decreased Na content and promoted K content, thereby promoting Na/K homeostasis and cucumber growth under salt stress. Moreover, Si ameliorated the K leakage induced by both salt and simulated oxidative stress, which was further confirmed by the results of selective ion electrolyte technique (SIET). Meanwhile, Si enhanced antioxidant enzyme activity, total antioxidant capacity, and the expression of genes related to antioxidant system in cucumber root under salt stress. In addition, Si treatment enhanced root Na exclusion under salt stress, which could be based on the upregulated expression of SOS and NHX genes. Overall, our results show that Si can enhance root K retention in cucumber by promoting root Na exclusion and antioxidant capacity, thereby alleviating salt stress.
盐胁迫会导致钾（K）泄漏和缺乏，从而限制植物生长。钾泄漏的减少（也称为钾保留）在植物耐盐性中起关键作用。硅（Si）可以缓解盐胁迫并促进植物的钾营养状况，但其背后的机制仍不清楚。在本研究中，研究了硅对黄瓜根系钾保留的调节作用及相关机制。结果表明，盐胁迫显著抑制黄瓜生长，导致钠积累和钾缺乏，而硅降低了钠含量，促进了钾含量，从而在盐胁迫下促进了钠/钾稳态和黄瓜生长。此外，硅改善了盐胁迫和模拟氧化胁迫诱导的钾泄漏，选择性离子电解质技术（SIET）的结果进一步证实了这一点。同时，硅增强了盐胁迫下黄瓜根系的抗氧化酶活性、总抗氧化能力以及与抗氧化系统相关基因的表达。此外，硅处理增强了盐胁迫下根系对钠的外排，这可能基于SOS和NHX基因表达的上调。总体而言，我们的结果表明，硅可以通过促进根系对钠的外排和抗氧化能力来增强黄瓜根系的钾保留，从而缓解盐胁迫。
