Salt stress as one of main abiotic stresses damaged plant growth and development. In this study, the effects of ethylene on Ca²⁺-regulated rooting index, Na⁺ and K⁺ concentration, Na⁺ transportation and cell ultrastructure during adventitious rooting in cucumber (Cucumis sativus L.) under salt stress were investigated. The results showed that ethylene might play a positive role in Ca²⁺-regulated rooting index during adventitious rooting under salt stress. Moreover, CaCl₂ treatment significantly decreased the intracellular Na⁺ level but increased K⁺ content of cucumber explants under salt stress. However, the Na⁺ and K⁺ concentration which treated with Ca²⁺ treatment was significantly influenced by ethylene inhibitors under salt stress. Our results also showed that ethylene might be involved in Ca²⁺-affected cell ultrastructure of cucumber explants under salt condition. Further analysis showed that ethylene might be responsible for Ca²⁺-regulated Na⁺ transport through enhancing the transcriptional and protein levels of Na⁺/H⁺ antiporter as well as H⁺-ATPase for alleviating the negative effects of NaCl stress. Therefore, ethylene might act as a downstream signaling molecule of Ca²⁺ to maintain Na⁺ and K⁺ homeostasis via regulating Na⁺ transport and preserve the integrity of cellular ultrastructure of cucumber explant during adventitious rooting under salt condition.

中文翻译：

---

乙烯在盐胁迫下不定根中参与Ca 2+调控的Na +稳态，Na +转运和细胞超微结构

盐胁迫作为主要的非生物胁迫之一，破坏了植物的生长发育。本研究研究了乙烯对盐胁迫下黄瓜（Cacumis sativus L.）不定根生根过程中Ca ²⁺调节生根指数，Na ⁺和K ⁺浓度，Na ⁺转运和细胞超微结构的影响。结果表明，乙烯在盐胁迫下不定根生根过程中可能对Ca ²⁺调控的生根指数起积极作用。此外，CaCl ₂处理可显着降低细胞内Na ⁺水平，但增加K ⁺盐胁迫下黄瓜外植体的含量 然而，在盐胁迫下，乙烯抑制剂显着影响了用Ca ²⁺处理的Na ⁺和K ^+的浓度。我们的研究结果还表明，在盐条件下，乙烯可能参与了Ca ²⁺介导的黄瓜外植体细胞超微结构。进一步分析显示，乙烯可能负责钙²⁺ -调节的Na ⁺运输通过提高Na组成的转录和蛋白质水平⁺ / H ⁺反向转运体，以及以H ⁺-ATPase减轻NaCl胁迫的负面影响。因此，乙烯可能作为Ca ²⁺的下游信号分子，通过调节Na ^+的运输来维持Na ⁺和K ^+的稳态，并在盐条件下不定根期间保持黄瓜外植体细胞超微结构的完整性。