bHLH (basic helix-loop-helix)作为植物界第2大类转录因子，在植物应对环境胁迫响应中起着重要的调控作用。探究马铃薯(Solanum tuberosum L.) bHLH家族基因功能将为马铃薯改良和育种提供一定的理论依据。本研究克隆了马铃薯StFBH3基因(Gene ID: 102582309)，利用qPCR技术分析了不同逆境胁迫下StFBH3基因表达模式，结果表明，StFBH3基因在马铃薯根和叶中的表达量较高，且该基因的表达受渗透、高盐和脱落酸(abscisic acid, ABA)诱导；以过表达StFBH3基因的马铃薯试管苗为材料，在分别含有不同浓度甘露醇(mannitol)、NaCl和ABA的MS培养基中，过表达StFBH3马铃薯株系的叶绿素含量显著高于野生型，根长显著长于野生型。在干旱和高盐处理下，土壤栽培的过表达马铃薯株系较野生型表现较强的耐受性，叶片相对含水量、叶绿素含量和过氧化物歧化酶(SOD)酶活性显著高于野生型。qPCR分析发现，干旱和盐胁迫相关基因(KAT1)在过表达马铃薯株系中较野生型表达量显著降低。以上结果表明，StFBH3基因可能在马铃薯对渗透、干旱和高盐等胁迫响应中起正向调控作用。本研究也为StFBH3基因在马铃薯中的生物学功能深入理解提供了一定的参考依据。

The basic helix-loop-helix (bHLH) transcription factor family is the second largest family of transcription factors and plays a central regulatory role in enabling plants to defend against environmental stress. Investigating the function of bHLH family genes in potato can provide a theoretical foundation for potato improvement and breeding. In this study, the StFBH3 gene was cloned, and its tissue-specific expression patterns under different stress treatments were analyzed using qPCR. The relative expression level of StFBH3 was highest in potato roots and leaves, and its expression was induced by osmotic stress, high salinity, and abscisic acid (ABA) treatment. On MS medium containing various concentrations of mannitol, NaCl, and ABA, the chlorophyll content in the StFBH3 overexpressing potato lines was significantly higher than that of the wild type, and the root length was notably longer. Under drought and high salinity conditions, the StFBH3 overexpressing lines cultivated in soil exhibited stronger tolerance compared to the wild type, with significantly higher leaf relative water content, chlorophyll content, and superoxide dismutase (SOD) enzyme activity. Furthermore, qPCR analysis revealed that the expression levels of drought- and salt stress-related genes, such as KAT1, were significantly reduced in the StFBH3 overexpressing lines compared to the wild type. These results suggest that StFBH3 functions as a positive regulator, induced and specifically expressed in response to osmotic stress, drought, and high salinity. This study provides an important reference for further analysis of the biological function of the StFBH3 gene in potato.