Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, 58 Renmin Avenue, , Haikou, 570228, Hainan, China.
College of Animal Science and Technology, Yangzhou University, 88 South Daxue Road, Yangzhou, 225009, Jiangsu, China.
BMC Plant Biol. 2023 Jun 24;23(1):337. doi: 10.1186/s12870-023-04358-w.
Soil salinization is a growing issue that limits agriculture globally. Understanding the mechanism underlying salt tolerance in halophytic grasses can provide new insights into engineering plant salinity tolerance in glycophytic plants. Seashore paspalum (Paspalum vaginatum Sw.) is a halophytic turfgrass and genomic model system for salt tolerance research in cereals and other grasses. However, the salt tolerance mechanism of this grass largely unknown. To explore the correlation between Na accumulation and salt tolerance in different tissues, we utilized two P. vaginatum accessions that exhibit contrasting tolerance to salinity. To accomplish this, we employed various analytical techniques including ICP-MS-based ion analysis, lipidomic profiling analysis, enzyme assays, and integrated transcriptomic and metabolomic analysis. Under high salinity, salt-tolerant P. vaginatum plants exhibited better growth and Na uptake compared to salt-sensitive plants. Salt-tolerant plants accumulated heightened Na accumulation in their roots, leading to increased production of root-sourced HO, which in turn activated the antioxidant systems. In salt-tolerant plants, metabolome profiling revealed tissue-specific metabolic changes, with increased amino acids, phenolic acids, and polyols in roots, and increased amino acids, flavonoids, and alkaloids in leaves. High salinity induced lipidome adaptation in roots, enhancing lipid metabolism in salt-tolerant plants. Moreover, through integrated analysis, the importance of amino acid metabolism in conferring salt tolerance was highlighted. This study significantly enhances our current understanding of salt-tolerant mechanisms in halophyte grass, thereby offering valuable insights for breeding and genetically engineering salt tolerance in glycophytic plants.
土壤盐渍化是一个日益严重的问题，限制了全球的农业发展。了解盐生植物耐盐性的机制可以为工程植物耐盐性提供新的思路，盐生植物耐盐性的工程植物。海滨雀稗（Paspalum vaginatum Sw.）是一种盐生草坪草，也是禾本科和其他禾本科植物耐盐性研究的基因组模式系统。然而，这种草的耐盐机制在很大程度上尚不清楚。为了探讨不同组织中钠积累与耐盐性的相关性，我们利用了两个耐盐性差异较大的海滨雀稗品系。为此，我们采用了多种分析技术，包括基于 ICP-MS 的离子分析、脂质组学分析、酶活性测定以及整合的转录组学和代谢组学分析。在高盐胁迫下，耐盐性海滨雀稗植株的生长和 Na 吸收优于盐敏感植株。耐盐性植株在根部积累了更高水平的 Na，导致根源性 HO 的产生增加，从而激活了抗氧化系统。在耐盐性植株中，代谢组学分析揭示了组织特异性的代谢变化，根部的氨基酸、酚酸和多元醇增加，叶片中的氨基酸、类黄酮和生物碱增加。高盐诱导了根部的脂质组适应，增强了耐盐性植株的脂质代谢。此外，通过整合分析，强调了氨基酸代谢在赋予植物耐盐性方面的重要性。本研究显著提高了我们对盐生禾本科植物耐盐机制的认识，为培育和遗传工程耐盐性提供了有价值的见解。
