盐胁迫下硫化氢信号系统调控加工番茄耐盐性机理研究

Processing tomato was one of the main pillar industries in the economic development of Xinjiang. But the climate conditions of drought, less rain and high evaporation have caused the secondary salinization of soil to threaten the development of processing tomato industry in Xinjiang. H2S plays an important role in regulating plant growth and environmental stress response. In this project, two processed tomato varieties with different salt tolerance were used as materials, the response mechanism of H2S and NO, CO and Ca2+ signal molecules to salt stress and the role of H2S signal transduction in improving salt resistance of plants by regulating photosynthetic carbon assimilation and ion microdomain distribution were researched under salt stress.The signal transduction pathway and resistance mechanism of salt stress between H2S and NO, CO , Ca2+, plant hormones (ABA and SA) by regulate photosynthetic carbon assimilation and ion microdomain distribution were realed. The research is expected to establish a new H2S signal transduction interaction network in salt tolerance . It provides feasible measures and new ways to reduce the harm of salt stress to processing tomato.

加工番茄是新疆发展地区经济的主要支柱产业之一，但新疆干旱少雨、蒸发量大的气候条件导致土壤次生盐渍化却威胁着加工番茄产业的发展。H2S在调控植物生长发育与环境因子胁迫响应过程中发挥重要作用。本项目以耐盐性强弱不同的两个加工番茄品系为材料，结合盐胁迫因子，研究H2S与NO、CO和Ca2+信号分子对盐胁迫的响应机制及H2S信号转导调控光合碳同化和离子的吸收微域分布在提高植物抗盐性中的作用。重点揭示盐胁迫下H2S与NO、CO和Ca2+信号分子交叉互作，与植物激素（ABA和SA等）相互应答通过调控光合碳同化和离子微域分布提高加工番茄耐盐性中的信号转导通路和抗性机理。研究有望建立新的H2S信号转导交互网络参与植物抗盐性，为减轻盐分胁迫逆境对加工番茄的危害，提高加工番茄耐盐性提供可行性措施和新的途径。

针对新疆大面积盐渍化土地导致加工番茄光合受抑、生长不良、产量和品质降低等问题，以加工番茄为试材，利用H2S与Ca2+、CO、NO信号分子供体（NaHS、CaCl2、Hemin、SNP）和植物激素SA及其清除剂或抑制剂（HT、EGTA、LaCl3、TFP、W7、ZnPPIX、cPTIO、ABT）等，探讨盐胁迫下H2S与Ca2+、CO、NO信号分子及SA信号互作调控加工番茄光合与抗盐性机理。结果表明：. （1）外源H2S、Ca2+、CO、NO和SA均能促进盐胁迫下加工番茄幼苗生长，提高渗透调节物质含量、抗氧化酶活性和光合参数维持较高光能转换，提高耐盐性。. （2）H2S和Ca2+可上调盐胁迫下加工番茄幼苗抗氧化酶基因表达、改善光合能力。清除钙会减弱H2S缓解盐胁迫作用，H2S清除剂削弱Ca2+对盐胁迫缓解效应。. （3）H2S、CO和NO均能提高盐胁迫下加工番茄幼苗Fv/Fm、Y(Ⅱ)、NPQ/4，降低Y(NO)和qL，提高非光化学淬灭降低光化学淬灭，降低光损伤提高叶绿素荧光量子产量，提高活性反应中心天线尺寸和稳定性缓解盐胁迫对光系统的伤害。H2S清除剂不影响CO缓解盐胁迫的作用，CO清除剂降低H2S对盐胁迫缓解效应。NO提高了盐胁迫下加工番茄幼苗H2S含量，H2S不能提高NO含量，NO清除剂降低H2S含量且对H2S缓解盐胁迫无影响，H2S清除剂对NO含量无影响且降低NO对盐胁迫缓解效应。. （4）H2S减少盐胁迫下加工番茄幼苗Na+的积累缓解盐胁迫，SA增加Ca2+、K+、Mg2+的吸收和减少Na+在体内积累来缓解盐胁迫损伤。H2S清除剂减弱SA缓解盐胁迫作用效果，SA抑制剂对H2S缓解盐胁迫的作用无明显影响。.可见，H2S作为信号系统调控加工番茄耐盐性，Ca2+与H2S具有互作效应，NO和SA作为H2S的上游信号，而CO作为H2S的下游信号参与调控盐胁迫下加工番茄光合和耐盐性。