结论:硝普钠通过调节亚硝酸和氧化途径介导番茄的干旱胁迫反应,强调一氧化氮之间的相互作用,硫化氢,和抗氧化系统,以增强耐旱性。而一氧化氮(NO),一个信号分子,增强植物对非生物胁迫的耐受性,尚未完全了解其通过调节氧化物-亚硝基过程对提高番茄对干旱胁迫(DS)的耐受性的确切贡献。我们的目的是检查NO和亚硝基信号的相互作用,揭示了硝普钠(SNP)如何减轻DS对西红柿的影响。DS幼苗在10%营养液(NS)中忍受12%聚乙二醇(PEG)2天,然后与对照植物一起过渡到半强度NS10天。DS降低了植物总干重,叶绿素a和b,Fv/Fm,叶水势(ΦI),和相对含水量,但改善了过氧化氢(H2O2),脯氨酸,没有内容。SNP通过还原硫醇(-SH)和羰基(-CO)基团来减少DS诱导的H2O2生成。SNP不仅增加NO,而且增加L-半胱氨酸脱硫水解酶(L-DES)的活性,导致H2S的产生。S-亚硝基谷胱甘肽还原酶(GSNOR)和NADPH氧化酶(NOX)的降低提示了一种潜在的调节机制,其中S-亚硝基化[S-亚硝基硫醇(SNO)的形成]可能会影响DS期间的蛋白质功能和信号通路。此外,SNP改善了干旱下番茄植株中抗坏血酸(AsA)和谷胱甘肽(GSH)的水平,并降低了氧化谷胱甘肽(GSSG)的水平。此外,NO和H2S的相互作用,由L-DES活性介导,可能是影响植物对DS反应的重要串扰机制。了解这些信号相互作用对于开发作物的创新抗旱策略至关重要。
CONCLUSIONS: Sodium nitroprusside mediates drought stress responses in tomatoes by modulating nitrosative and oxidative pathways, highlighting the interplay between nitric oxide, hydrogen sulfide, and antioxidant systems for enhanced drought tolerance. While nitric oxide (NO), a signalling molecule, enhances plant tolerance to abiotic stresses, its precise contribution to improving tomato tolerance to drought stress (DS) through modulating oxide-nitrosative processes is not yet fully understood. We aimed to examine the interaction of NO and nitrosative signaling, revealing how sodium nitroprusside (SNP) could mitigate the effects of DS on tomatoes. DS-seedlings endured 12% polyethylene glycol (PEG) in a 10% nutrient solution (NS) for 2 days, then transitioned to half-strength NS for 10 days alongside control plants. DS reduced total plant dry weight, chlorophyll a and b, Fv/Fm, leaf water potential (ΨI), and relative water content, but improved hydrogen peroxide (H2O2), proline, and NO content. The SNP reduced the DS-induced H2O2 generation by reducing thiol (-SH) and the carbonyl (-CO) groups. SNP increased not only NO but also the activity of L-cysteine desulfhydrase (L-DES), leading to the generation of H2S. Decreases in S-nitrosoglutathione reductase (GSNOR) and NADPH oxidase (NOX) suggest a potential regulatory mechanism in which S-nitrosylation [formation of S-nitrosothiol (SNO)] may influence protein function and signaling pathways during DS. Moreover, SNP improved ascorbate (AsA) and glutathione (GSH) and reduced oxidized glutathione (GSSG) levels in tomato plants under drought. Furthermore, the interaction of NO and H2S, mediated by L-DES activity, may serve as a vital cross-talk mechanism impacting plant responses to DS. Understanding these signaling interactions is crucial for developing innovative drought-tolerance strategies in crops.