Plant Omics Division, CSIR- Central Salt and Marine Chemicals Research Institute (CSIR-CSMCRI), Gijubhai Badheka Marg, Bhavnagar, 364002, Gujarat, India.
Academy of Scientific and Innovative Research (AcSIR), Gaziabad, 201002, India.
Planta. 2023 Nov 1;258(6):109. doi: 10.1007/s00425-023-04263-4.
Arsenic tolerance in the halophyte Salvadora persica is achieved by enhancing antioxidative defense and modulations of various groups of metabolites like amino acids, organic acids, sugars, sugar alcohols, and phytohormones. Salvadora persica is a facultative halophyte that thrives under high saline and arid regions of the world. In present study, we examine root metabolic responses of S. persica exposed to individual effects of high salinity (750 mM NaCl), arsenic (600 µM As), and combined treatment of salinity and arsenic (250 mM NaCl + 600 µM As) to decipher its As and salinity resistance mechanism. Our results demonstrated that NaCl supplementation reduced the levels of reactive oxygen species (ROS) under As stress. The increased activities of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR) maintained appropriate levels of ROS [superoxide (O) and hydrogen peroxide (HO)] under salinity and/or As stress. The metabolites like sugars, amino acids, polyphenols, and organic acids exhibited higher accumulations when salt was supplied with As. Furthermore, comparatively higher accumulations of glycine, glutamate, and cystine under combined stress of salt and As may indicate its role in glutathione and phytochelatins (PCs) synthesis in root. The levels of phytohormones such as salicylate, jasmonate, abscisic acid, and auxins were significantly increased under high As with and without salinity stress. The amino acid metabolism, glutathione metabolism, carbohydrate metabolism, tricarboxylic acid cycle (TCA cycle), phenylpropanoid biosynthesis, and phenylalanine metabolism are the most significantly altered metabolic pathways in response to NaCl and/or As stress. Our study decoded the important metabolites and metabolic pathways involved in As and/or salinity tolerance in root of the halophyte S. persica providing clues for development of salinity and As resistance crops.
在盐生植物沙柳树中，砷耐受性是通过增强抗氧化防御和调节各种代谢物群来实现的，如氨基酸、有机酸、糖、糖醇和植物激素。沙柳树是一种兼性盐生植物，在世界上高盐和干旱地区生长旺盛。在本研究中，我们研究了沙柳树根在单独暴露于高盐（750 mM NaCl）、砷（600 µM As）和盐和砷联合处理（250 mM NaCl + 600 µM As）下的代谢反应，以破译其砷和耐盐机制。我们的结果表明，NaCl 补充降低了砷胁迫下活性氧（ROS）的水平。抗氧化酶如超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPX）和谷胱甘肽还原酶（GR）的活性增加，在盐和/或砷胁迫下维持 ROS [超氧阴离子（O）和过氧化氢（HO）]的适当水平。当盐与砷一起供应时，糖、氨基酸、多酚和有机酸等代谢物的积累更高。此外，在盐和砷联合胁迫下，甘氨酸、谷氨酸和半胱氨酸的积累较高，这可能表明它们在谷胱甘肽和植物螯合肽（PCs）合成中的作用。在高砷胁迫下，水杨酸、茉莉酸、脱落酸和生长素等植物激素的水平显著升高，无论是否存在盐胁迫。氨基酸代谢、谷胱甘肽代谢、碳水化合物代谢、三羧酸循环（TCA 循环）、苯丙烷生物合成和苯丙氨酸代谢是对 NaCl 和/或 As 胁迫反应中变化最大的代谢途径。我们的研究解码了盐生植物沙柳树根中涉及砷和/或耐盐性的重要代谢物和代谢途径，为开发耐盐和砷的作物提供了线索。
