Integrated signaling network involving abscisic acid (ABA), nitric oxide (NO), and indole-acetic acid (IAA) controls root morphogenesis during salt stress by a mechanism still poorly understood. The present data unveiled an ABA-NO-IAA interaction underlying radicular morphological responses to salinity. Three Solanum lycopersicum genotypes were analyzed: wild type, ABA-insensitive mutant (sitiens), and auxin-responsive (DR5::GUS) plants. Nitric oxide fluorescence, nitrate reductase activity, auxin signaling, and some molecular analyses were performed. Pharmacological inhibitors and NO donor sodium nitroprusside were also used to evaluate NaCl-induced root morphological responses. Sodium nitroprusside inhibited primary root length, increased lateral root emergence, and rescued salt inhibited lateral root growth. The results showed that NO integrates the ABA-IAA signaling network of root system responses under salt stress, involving: (a) ABA and molybdenum-dependent enzymes as responsible for salt-induced NO production; (b) modulations of the plasma membrane H⁺-ATPase coupling and isoforms differential expression; and (c) ABA-mediated and NO-dependent antioxidative enzymes activities.

涉及脱落酸（ABA），一氧化氮（NO）和吲哚-乙酸（IAA）的综合信号网络通过一种尚不清楚的机制来控制盐胁迫期间的根系形态发生。目前的数据揭示了对盐度的放射形态响应的ABA-NO-IAA相互作用。分析了三种茄属番茄的基因型：野生型，对ABA不敏感的突变体（sitiens）和对植物生长素的响应型（DR5 :: GUS）植物。一氧化氮荧光，硝酸还原酶活性，生长素信号传导和一些分子分析进行了。药理抑制剂和NO供体硝普钠也用于评估NaCl诱导的根系形态反应。硝普钠抑制初生根的长度，增加侧根的出苗，并抢救盐抑制侧根的生长。结果表明，NO整合了盐胁迫下根系响应的ABA-IAA信号网络，涉及：（a）ABA和钼依赖性酶负责盐诱导的NO产生；（b）调节质膜H ⁺ -ATPase偶联和同工型差异表达；（c）ABA介导的和NO依赖性的抗氧化酶活性。