以甘肃柽柳（Tamarix gansuensis H. Z. Zhang）、多枝柽柳（T. ramosissima Ledeb.）和细穗柽柳（T. leptostachys Bunge）为研究对象，采用液体培养法对100、200和300 mmol·L^-1 NaCl胁迫20 d后3种植物的生长和盐离子分布进行了比较；在此基础上，对300 mmol·L^-1 NaCl胁迫30 d后3种植物的生长和生理指标以及300 mmol·L^-1 NaCl胁迫0、3、6、12和24 h后3种植物地上部和根中SOS1基因的相对表达量进行了比较。结果表明：与0 mmol·L^-1 NaCl（对照）相比，3种植物的株高和单株干质量在100 mmol·L^-1 NaCl胁迫下升高，但在300 mmol·L^-1 NaCl胁迫下降低。随着NaCl浓度提高，3种植物地上部和根的Na+和Cl-含量和Na+／K+比逐渐升高，而K+含量逐渐下降，其中细穗柽柳地上部和根的Na+和Cl-含量及Na+／K+比较高。与对照相比，300 mmol·L^-1 NaCl胁迫下3种植物地上部表面泌盐明显增多，叶绿素a、叶绿素b、总叶绿素和类胡萝卜素含量基本上显著（P＜0.05）升高，但植株生长受到明显抑制，根系活力、地上部相对含水量和地上部离体失水率明显下降。总体来看，多枝柽柳的相对株高增长量最大，根冠比最小，地上部相对含水量和地上部离体失水率降幅均最小，说明其地上部生长受NaCl胁迫的抑制程度较小。300 mmol·L^-1 NaCl胁迫0 h，3种植物地上部和根中SOS1基因的相对表达量无明显差异，但在胁迫24 h不同程度升高，其中多枝柽柳地上部中SOS1基因的相对表达量增幅最大，其根中SOS1基因的相对表达量增幅也较大。总体来看，3种植物的耐盐能力均较强，NaCl胁迫对多枝柽柳的影响最小，因此，可将多枝柽柳作为柽柳属（Tamarix Linn.）植物耐盐生理和分子机制研究的备选材料。

Taking Tamarix gansuensis H. Z. Zhang， T. ramosissima Ledeb.， and T. leptostachys Bunge as research objects， growth and salt ion distribution of three species were compared under 100， 200， and 300 mmol·L^-1 NaCl stress for 20 d by using liquid cultivation method. On the basis， growth and physiological indexes of three species under 300 mmol·L^-1 NaCl stress for 30 d and relative expression of SOS1 gene in above-ground part and root under 300 mmol·L^-1 NaCl stress for 0， 3， 6， 12， and 24 h were compared. The results show that compared with 0 mmol·L^-1 NaCl （the control）， height and dry mass per plant of three species increase under 100 mmol·L^-1 NaCl stress， but decrease under 300 mmol·L^-1 NaCl stress. With the increase of NaCl concentration， contents of Na+ and Cl- and Na+／K+ ratio in above-ground part and root of three species increase gradually， while K+ content decreases gradually， in which， contents of Na+ and Cl- and Na+／K+ ratio in above-ground part and root of T. leptostachys are high. Compared with the control， salt excretion on surface of above-ground part of three species increase evidently under 300 mmol·L^-1 NaCl stress， and contents of chlorophyll a， chlorophyll b， total chlorophyll， and carotenoid basically increase significantly （P＜0.05）， but plant growth is markedly suppressed， and root vigor， relative water content in above-ground part and water loss rate of above-ground part in vitro decrease obviously. In general， relative height increment of T. ramosissima is the largest， root／shoot ratio is the smallest， and decreasing amplitude of relative water content in above-ground part and water loss rate of above-ground part in vitro are both the smallest， indicating that the suppression degree of growth of its above-ground part under NaCl stress is small. Under 300 mmol·L^-1 NaCl stress for 0 h， there is no significant difference in relative expression of SOS1 gene in above-ground part and root among three species， but there is an increament at different degrees when stress for 24 h， in which， increasing amplitude of relative expression of SOS1 gene in above-ground part of T. ramosissima is the largest， and that in its root is also large. In general， salt-tolerant ability of three species is strong, and the effect of NaCl stress on T. ramosissima is the least， so T. ramosissima can be used as alternative material for studying salt-tolerant physiology and molecular mechanism of Tamarix Linn. species.