Kumari Asha, Fatnani Dhara, Seth Chandra Shekhar, Parida Asish Kumar
Plant Omics Division, CSIR- Central Salt and Marine Chemicals Research Institute (CSIR-CSMCRI), Gijubhai Badheka Marg, Bhavnagar, Gujarat, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
Physiol Plant. 2025 Jan-Feb;177(1):e70114. doi: 10.1111/ppl.70114.
Soil salinization and alkalization are the foremost abiotic stresses adversely affecting plant growth and yield worldwide. Salvadora persica is an important facultative halophyte that has been reported for its high salinity tolerance ability. The present study undertakes the growth, photosynthetic efficiency, chlorophyll fluorescence, antioxidative defense, ionomic adjustments, and metabolomic responses of S. persica to understand its resilience mechanisms under saline-alkali stress. Our findings reveal that S. persica undergoes substantial physiological, ionomic, and metabolic modulations for endurance under saline-alkali stress. Under saline-alkali stress, metabolomic analysis identified 75 differentially accumulated metabolites (DAMS), including amino acids, sugars, sugar alcohols, organic acids, polyphenols, and phytohormones. Notable upregulated metabolites included quercetin (+4-fold), naringenin (+2.6-fold), glycerol (+2.4-fold), and proline (+1.7-fold), whereas D-mannitol (-3.8-fold), D-talose (-2.9-fold), and GA3 (-2.8-fold) were significantly downregulated. Pathway enrichment analysis revealed alterations in key metabolic pathways, such as amino acid metabolism, starch and sucrose metabolism, tricarboxylic acid cycle (TCA cycle), glycolysis/gluconeogenesis, and photosynthetic carbon fixation. A 2-fold reduction in glucose indicated an enhanced glycolytic flux to support energy needs under stress. The study highlights S. persica's adaptive strategy of slower nitrogen metabolism, increased glycolysis, and downregulated TCA cycle, giving an indication towards a slower growth rate under saline-alkali stress to reallocate energy for osmolyte biosynthesis. The amino acids, sugars, and sugar alcohols emerged as major contributors to osmotic adjustment. A robust antioxidant defense system exists in S. persica to mitigate ROS under saline-alkali stress. These findings provide insights into the mechanisms of saline-alkali tolerance in the halophyte S. persica, offering valuable direction for developing saline-alkali-tolerant crops.
土壤盐碱化是全球范围内对植物生长和产量产生不利影响的首要非生物胁迫因素。海巴戟是一种重要的兼性盐生植物，据报道具有较高的耐盐能力。本研究对海巴戟的生长、光合效率、叶绿素荧光、抗氧化防御、离子组学调节和代谢组学响应进行了研究，以了解其在盐碱胁迫下的适应机制。我们的研究结果表明，海巴戟在盐碱胁迫下经历了显著的生理、离子组学和代谢调节以实现耐受。在盐碱胁迫下，代谢组学分析鉴定出75种差异积累代谢物（DAM），包括氨基酸、糖类、糖醇、有机酸、多酚和植物激素。显著上调的代谢物包括槲皮素（+4倍）、柚皮素（+2.6倍）、甘油（+2.4倍）和脯氨酸（+1.7倍），而D-甘露醇（-3.8倍）、D-塔罗糖（-2.9倍）和赤霉素3（-2.8倍）则显著下调。通路富集分析揭示了关键代谢通路的变化，如氨基酸代谢、淀粉和蔗糖代谢、三羧酸循环（TCA循环）、糖酵解/糖异生作用以及光合碳固定。葡萄糖减少2倍表明在胁迫下糖酵解通量增强以满足能量需求。该研究突出了海巴戟在盐碱胁迫下氮代谢减缓、糖酵解增加和TCA循环下调的适应策略，这表明其在盐碱胁迫下生长速率较慢，以便为渗透调节物质的生物合成重新分配能量。氨基酸、糖类和糖醇是渗透调节的主要贡献者。海巴戟存在强大的抗氧化防御系统以减轻盐碱胁迫下的活性氧。这些发现为盐生植物海巴戟的耐盐碱机制提供了见解，为培育耐盐碱作物提供了有价值的指导。
