Acharya Biswa R, Gill Satwinder Pal, Kaundal Amita, Sandhu Devinder
US Salinity Laboratory, USDA-ARS, Riverside, CA, United States.
College of Natural and Agricultural Sciences, University of California Riverside, Riverside, CA, United States.
Front Plant Sci. 2024 Jul 15;15:1406913. doi: 10.3389/fpls.2024.1406913. eCollection 2024.
Global climate change and the decreasing availability of high-quality water lead to an increase in the salinization of agricultural lands. This rising salinity represents a significant abiotic stressor that detrimentally influences plant physiology and gene expression. Consequently, critical processes such as seed germination, growth, development, and yield are adversely affected. Salinity severely impacts crop yields, given that many crop plants are sensitive to salt stress. Plant growth-promoting microorganisms (PGPMs) in the rhizosphere or the rhizoplane of plants are considered the "second genome" of plants as they contribute significantly to improving the plant growth and fitness of plants under normal conditions and when plants are under stress such as salinity. PGPMs are crucial in assisting plants to navigate the harsh conditions imposed by salt stress. By enhancing water and nutrient absorption, which is often hampered by high salinity, these microorganisms significantly improve plant resilience. They bolster the plant's defenses by increasing the production of osmoprotectants and antioxidants, mitigating salt-induced damage. Furthermore, PGPMs supply growth-promoting hormones like auxins and gibberellins and reduce levels of the stress hormone ethylene, fostering healthier plant growth. Importantly, they activate genes responsible for maintaining ion balance, a vital aspect of plant survival in saline environments. This review underscores the multifaceted roles of PGPMs in supporting plant life under salt stress, highlighting their value for agriculture in salt-affected areas and their potential impact on global food security.
全球气候变化和优质水资源的减少导致农业土地盐碱化加剧。这种不断上升的盐度是一种重要的非生物胁迫因素，对植物生理和基因表达产生不利影响。因此，种子萌发、生长、发育和产量等关键过程受到负面影响。鉴于许多农作物对盐胁迫敏感，盐度严重影响作物产量。植物根际或根表的植物促生微生物（PGPMs）被视为植物的“第二基因组”，因为它们在正常条件下以及植物处于盐度等胁迫状态时，对促进植物生长和提高植物适应性有显著贡献。PGPMs在帮助植物应对盐胁迫带来的恶劣条件方面至关重要。通过增强水分和养分吸收（这往往因高盐度而受阻），这些微生物显著提高了植物的恢复力。它们通过增加渗透保护剂和抗氧化剂的产生来增强植物的防御能力，减轻盐诱导的损害。此外，PGPMs提供生长素和赤霉素等促生长激素，并降低胁迫激素乙烯的水平，促进植物更健康地生长。重要的是，它们激活负责维持离子平衡的基因，这是植物在盐碱环境中生存的一个重要方面。本综述强调了PGPMs在盐胁迫下支持植物生命的多方面作用，突出了它们对盐碱化地区农业的价值及其对全球粮食安全的潜在影响。
