Search Results (3)

Fatsia japonica (Thunb.) Decne. et Planch. is an important woody landscape plant, and its distribution is commonly limited by salt stress. Although the application of exogenous nitric oxide (NO) has been known to be effective in alleviating abiotic stress in plants, the underlying mechanism by which NO induces salt resistance in F. japonica remains unknown. In this study, the physiological and metabolic characteristics of F. japonica seedlings with the application of NO under salt stress conditions were investigated. We demonstrated that exogenous NO (0.1 mM sodium nitroprusside, SNP) mitigated the growth inhibition caused by 0.4% NaCl. This alleviation could be attributed to NO-induced enhancement in photosynthesis, osmotic adjustment, antioxidant enzyme activities, and a reduction in oxidative damage when exposed to salt stress. Furthermore, the metabolomic analysis revealed that salt stress significantly disrupts the growth of F. japonica by downregulating sugars, sugar alcohols, amino acids, and organic acids. However, the application of exogenous NO improves sugar metabolism, enhancing the levels of fructose, glucose, mannose, galactose, xylose, ribose, inositol, and sorbitol, as well as the metabolism of amino acids and organic acids. These findings provide new insights into the physiological and metabolic homeostasis adjustments induced by NO that promote salt stress tolerance in F. japonica, enhancing our understanding of plant resilience mechanisms. Full article

Cyclocarya paliurus is commonly used to treat diabetes in China. However, the natural habitats of C. paliurus are typically affected by salt stress. Previous studies showed that nitric oxide (NO) level was related to salt tolerance of C. paliurus, and its synthesis was induced by exogenous hydrogen sulfide. However, the effects of different NO donors in alleviating the negative effect of salt stress are still unclear. In the present study, C. paliurus seedlings pretreated with three NO donors (S-nitroso-N-acetylpenicillamine, SNAP and S-nitrosoglutathione, GSNO and sodium nitroprusside, SNP) were exposed to salt stress, and then, the total biomass, chlorophyll fluorescence parameters, NO and glutathione levels, oxidative damage, and antioxidant enzyme activities were investigated. The results showed that pretreatment of NO donors maintained chlorophyll fluorescence and attenuated the loss of plant biomass under salt stress, and the best performance was observed in C. paliurus under SNP treatment. We also found that pretreatment of NO donors further increased the endogenous NO content and nitrate reductase (NR) activity compared with salt treatment. Moreover, pretreatment with NO donors, especially SNP, alleviated salt-induced oxidative damage, as indicated by lowered lipid peroxidation, through an enhanced antioxidant system including glutathione accumulation and increased antioxidant enzyme activities. The supply of NO donors is an interesting strategy for alleviating the negative effect of salt on C. paliurus. Our data provide new evidence contributing to the current understanding of NO-induced salt stress tolerance. Full article

Salinity is one of the major abiotic factors that limit rice production worldwide. Previous trends show that salt concentration in rivers is increasing consistently, posing potentially adverse threats in the near future. Thus, crops currently being cultivated, particularly in small-scale farming systems, are under high threat from salinity. In this study, we investigated the mitigating effect of nitric oxide (NO) on salt stress in rice based on the assessment of changes in the transcript levels of different genes and the phenotypic response of rice genotypes. We observed that exogenously applied NO increased the expression levels of OsHIPP38, OsGR1, and OsP5CS2 in the susceptible genotype of rice, whereas in the tolerant genotype, the effect of NO was mainly in counteracting the salt-induced gene expression that diverts cellular energy for defense. Moreover, seedlings that were pretreated with NO showed high biomass production under salt stress conditions, indicating the positive role of NO against salt-induced leaf chlorosis and early senescence. The effect of NO-mediated enhancement was more pronounced in the salt tolerant genotype. Therefore, the use of NO with the integration of tolerant genes or genotypes will enhance salt tolerance levels in rice. Full article