独脚金内酯参与富氢水增强番茄幼苗根系的耐盐性

nvolvement of strigolactone in hydrogen-rich water enhanced salt tolerance in tomato seedling roots

【目的】研究盐胁迫下氢气(H2)和独脚金内酯(SLs)在番茄幼苗根系中的调控作用及其相互关系。【方法】以番茄(Solanum lycopersicum L.‘Micro-Tom’)为试材,采用人工培养室基质栽培方式,确定最适浓度富氢水(75%)的基础上,设置如下处理:100%霍格兰营养液(CK)、盐胁迫(NaCl)、NaCl+HRW、NaCl+GR24(独脚金内酯合成类似物)、NaCl+HRW+TIS108(独脚金内酯合成抑制剂)。测定根系相关指标以及SLs含量及其相关合成基因表达量。【结果】盐胁迫下,75%HRW处理能显著增加番茄根系的长度、鲜质量和干质量。同时,GR24和HRW促进了盐胁迫下番茄幼苗的根系形态参数(根长、根表面积、根体积、平均直径等)和根系活力。然而,HRW的积极作用被SLs合成抑制剂TIS108所抑制。所以H2调节的番茄幼苗根系耐盐性可能SLs与有关。此外,HRW处理增加了盐胁迫下番茄幼苗根系的内源SLs含量。在盐胁迫下,HRW处理也显著上调了SLs生物合成相关基因SlCCD7、SlCCD8、SlD14和SlMAX1的表达水平。【结论】SLs可能参与了H2诱导的番茄幼苗根系的耐盐性。

【Objective】 To investigate the regulatory roles of hydrogen(H2) and strigolactones(SLs) and their interaction in the roots of tomato seedlings under salt stress.【Method】 Tomato(Solanum lycopersicum L.‘Micro-Tom') was used as the experimental material,and was grown in an artificial culture chamber substrate.Based on the optimum concentration of hydrogen-rich water(75%),the treatments are as follows:100% Hogland(CK),salt stress(NaCl),NaCl + HRW,NaCl + GR24(SLs synthesis),NaCl +HRW+ TIS108(SLs synthesis).Root related parameters,SLs content,and the expression of SLs biosynthesis related genes were determined.【Result】 Under salt stress,75% HRW treatment significantly increased root length,fresh weight,and dry weight of tomato seedling roots.Meanwhile,GR24 and HRW promoted root morphological parameters(root length,root surface area,root volume,root/shoot ratio,etc.) and root activity of tomato seedlings under salt stress.However,the beneficial roles of HRW were blocked by TIS108(SLs inhibitor).Thus,SLs may be responsible for H2-regulated salt stress tolerance in the root of tomato seedlings.Additionally,HRW treatment increased endogenous SLs levels in tomato seedling roots under salt stress.HRW treatment significantly up-regulated the expression levels of SLs biosynthesisrelated genes SlCCD7,SlCCD8,SlD14 and SlMAX1 under salt stress.【Conclusion】 SLs may be involved in H2-induced salt tolerance in the root of tomato seedlings.