Stefanov Martin A, Rashkov Georgi D, Yotsova Ekaterina K, Borisova Preslava B, Dobrikova Anelia G, Apostolova Emilia L
Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria.
Plants (Basel). 2023 Feb 13;12(4):832. doi: 10.3390/plants12040832.
In this study, the impacts of the foliar application of different sodium nitroprusside (SNP, as a donor of nitric oxide) concentrations (0-300 µM) on two sorghum varieties ( L. Albanus and L. Shamal) under salt stress (150 mM NaCl) were investigated. The data revealed that salinity leads to an increase in oxidative stress markers and damage of the membrane integrity, accompanied by a decrease in the chlorophyll content, the open photosystem II (PSII) centers, and the performance indexes (PI and PI ), as well as having an influence on the electron flux reducing photosystem I (PSI) end acceptors (REo/RC). Spraying with SNP alleviated the NaCl toxicity on the photosynthetic functions; the protection was concentration-dependent, and greater in Shamal than in Albanus, i.e., variety specific. Furthermore, the experimental results revealed that the degree of SNP protection under salt stress also depends on the endogenous nitric oxide (NO) amount in leaves, the number of active reaction centers per PSII antenna chlorophylls, the enhanced electron flux reducing end acceptors at the acceptor side of PSI, as well as the stimulation of the cyclic electron transport around PSI. The results showed better protection in both varieties of sorghum for SNP concentrations up to 150 µM, which corresponds to about a 50% increase in the endogenous NO leaf content in comparison to the control plants. Our study provides valuable insight into the molecular mechanisms underlying SNP-induced salt tolerance in sorghum varieties and might be a practical approach to correcting salt intolerance.
在本研究中，研究了在盐胁迫（150 mM NaCl）下，叶面喷施不同浓度（0 - 300 µM）的硝普钠（SNP，作为一氧化氮供体）对两个高粱品种（阿尔巴努斯高粱和沙马尔高粱）的影响。数据显示，盐度导致氧化应激标志物增加和膜完整性受损，同时叶绿素含量、开放的光系统II（PSII）中心和性能指标（PI和PI）降低，并且对还原光系统I（PSI）末端受体的电子通量（REo/RC）有影响。喷施SNP减轻了NaCl对光合功能的毒性；这种保护作用具有浓度依赖性，在沙马尔高粱中比在阿尔巴努斯高粱中更显著，即具有品种特异性。此外，实验结果表明，盐胁迫下SNP的保护程度还取决于叶片中内源性一氧化氮（NO）的含量、每个PSII天线叶绿素的活性反应中心数量、PSI受体侧还原末端受体的增强电子通量以及PSI周围循环电子传递的刺激。结果表明，对于高达150 µM的SNP浓度，两个高粱品种均表现出更好的保护作用，与对照植株相比，这相当于叶片内源性NO含量增加了约50%。我们的研究为高粱品种中SNP诱导的耐盐性潜在分子机制提供了有价值的见解，并且可能是纠正盐不耐受的一种实用方法。
