盐胁迫对长穗偃麦草根系分泌有机酸的影响

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中图分类号：S543.9 文献标识码：A 文章编号：1007-0435（2026）01-0001-09

Abstract：To elucidate the responses of organic acids secreted by the roots of Thinopyrum ponticum under salt stress and their interactions with root traits and rhizosphere soil physicochemical properties，a controlld experiment with foursalinitytreatmentswas established：control，mild，moderateandseveresaltstress（withsoil salt contents of 0% ， 0.2% ， 0.4% ，and 0.6% w/w，respectively）.Untargeted metabolomics was employed to analyze relative abundance variations and regulatory mechanisms of organic acids in root exudates.The results demonstrated that salt stress significantly decreased the secretion of organic acids including 1-hydroxy-2-naphthoic acid， succinic acid， homogentisic acid， phenylpyruvic acid and indolelactic acid （ ⋅P<0.05 ，while significantly enhancing the secretion of phenoxyacetic acid （ P<0.05 ）.However，no significant effects on the secretionof 3-hydroxybutyric acid and shikimic acid.Principal coordinate analysis（PCoA）revealed significant differ ences in root-secreted organic acid profiles between control and salt-stressed treatments （mild，moderate and severe salinity）（ .Correlation analysis demonstrated that soil salinity，electrical conductivity，water content，and pH were key determinants influencing root organic acid secretion. Path analysis further revealed that salt stress promoted phenoxyacetic acid secretion through soil salinization-mediated suppression of root morphological traits.These findings provide a theoretical basis for the in-depth analysis of the physiological mechanisms of plant salt tolerance.

Key Words：Salinization;Salt tolerance mechanism;Rhizosphere effect;Root exudates

盐渍化是草地退化的标志之一[1]，据统计，我国盐渍土地面积约为 3.7×107hm2 ，占我国陆地总面积的 3.84% ，占全球盐渍化土地总面积的3.36%[2] 。（剩余17906字）