Hassan Muhammad Jawad, Najeeb Atiqa, Zhou Min, Raza Muhammad Ali, Ali Ummar, Cheng Bizhen, Ling Yao, Li Zhou
College of Grassland Science and Technology, Sichuan Agricultural University, Chengdu, China.
Institute of Soil Fertilizer and Water Saving Agriculture, Gansu Academy of Agricultural Sciences, Lanzhou, China.
Front Plant Sci. 2024 Oct 11;15:1430752. doi: 10.3389/fpls.2024.1430752. eCollection 2024.
Diethyl aminoethyl hexanoate (DA-6) serving as a non-toxic and low-cost plant growth regulator is used for improving plant growth and stress tolerance, but the DA-6-mediated organic metabolites remodeling in relation to drought tolerance is not well documented in crops. The aims of the present study were to evaluate impacts of DA-6 on physiological functions including osmotic adjustment, photochemical efficiency, oxidative damage, and cell membrane stability as well as organic metabolites remodeling in white clover () leaves based on the analysis of metabolomics. Plants were foliarly treated with or without DA-6 and subsequently exposed to drought stress for 8 days. Results demonstrated that foliar application of DA-6 (1.5 mM) could significantly ameliorate drought tolerance, which was linked with better leaf water status, photosynthetic performance, and cell membrane stability as well as lower oxidative injury in leaves. Metabolic profiling of organic metabolites identified a total of 59 metabolites including 17 organic acids, 20 sugars, 12 alcohols, and 10 other metabolites. In response to drought stress, the DA-6 induced accumulations of many sugars and sugar alcohols (erythrulose, arabinose, xylose, inosose, galactose, talopyranose, fucose, erythritol, and ribitol), organic acids (propanoic acid, 2,3-dihydroxybutanoic acid, palmitic acid, linolenic acid, and galacturonic acid), and other metabolites (2-oxazoline, silane, and glycine) in white clover. These altered metabolites induced by the DA-6 could perform critical functions in maintenances of osmo-protection, osmotic adjustment, redox homeostasis, cell wall structure and membrane stability when white clover suffered from water deficit. In addition, the campesterol and stigmasterol significantly accumulated in all plants in spite of the DA-6 pretreatment under drought stress, which could be an important adaptive response to water deficit due to beneficial roles of those two metabolites in regulating cell membrane stability and antioxidant defense. Present findings provide new evidence of DA-6-regulated metabolic homeostasis contributing to drought tolerance in leguminous plants.
己酸二乙氨基乙醇酯（DA-6）作为一种无毒且低成本的植物生长调节剂，用于促进植物生长并提高其胁迫耐受性，但在作物中，关于DA-6介导的与耐旱性相关的有机代谢物重塑的研究报道较少。本研究的目的是基于代谢组学分析，评估DA-6对白三叶叶片生理功能的影响，包括渗透调节、光化学效率、氧化损伤和细胞膜稳定性，以及有机代谢物重塑。对植株进行叶面喷施DA-6或不喷施DA-6处理，随后使其遭受8天的干旱胁迫。结果表明，叶面喷施1.5 mM的DA-6能显著提高耐旱性，这与叶片更好的水分状况、光合性能和细胞膜稳定性以及较低的氧化损伤有关。对有机代谢物的代谢谱分析共鉴定出59种代谢物，包括17种有机酸、20种糖类、12种醇类和10种其他代谢物。响应干旱胁迫，DA-6诱导白三叶中许多糖类和糖醇（赤藓酮糖、阿拉伯糖、木糖、肌醇、半乳糖、塔罗糖、岩藻糖、赤藓醇和核糖醇）、有机酸（丙酸、2,3-二羟基丁酸、棕榈酸、亚麻酸和半乳糖醛酸）以及其他代谢物（2-恶唑啉、硅烷和甘氨酸）的积累。当白三叶遭受水分亏缺时，DA-6诱导的这些代谢物变化在维持渗透保护、渗透调节、氧化还原稳态、细胞壁结构和膜稳定性方面发挥关键作用。此外，尽管在干旱胁迫下进行了DA-6预处理，但所有植株中的菜油甾醇和豆甾醇均显著积累，这可能是对水分亏缺的一种重要适应性反应，因为这两种代谢物在调节细胞膜稳定性和抗氧化防御方面具有有益作用。目前的研究结果为DA-6调节的代谢稳态有助于豆科植物耐旱性提供了新证据。
