中文摘要：

[目的]以金叶接骨木为试验材料,用电阻抗图谱（EIS）法和电解质渗透率法测定根系抗盐碱性并构建其根系K含量模型,为简单快速地预测盐碱胁迫下金叶接骨木根系的K含量提供技术支持。[方法]研究不同浓度盐碱胁迫下金叶接骨木根系EIS图谱、细胞膜透性以及K含量的变化,将根系EIS参数与相应的K含量进行线性和非线性回归分析,选取最佳的EIS参数构建估测模型,并对模型进行精度检验。[结果]在胁迫处理期间,各浓度处理金叶接骨木根系K含量均显著低于对照（P≤0.05）;随着盐碱胁迫时间延长,各浓度处理下金叶接骨木根系的相对电导率呈现上升趋势,且均显著高于对照（P≤0.05）;随着盐碱胁迫时间延长,各浓度处理下金叶接骨木根系的电阻抗图谱变化不同;弛豫时间τ为估测金叶接骨木根系K含量的最佳EIS参数,最佳估测模型为y=0.005 5x3-0.232 8x2＋2.638 8＋15.877,预测精度达到91.73%。[结论]利用EIS参数构建的金叶接骨木根系K含量模型y=0.005 5x3-0.232 8x2＋2.638 8x＋15.877预测精度高,可以用于快速准确预测盐碱胁迫下金叶接骨木根系K含量的变化。

英文摘要：

[Objective]Sambucus canadensis was used as experimental material in this study. To simply and fastly predict K content in roots of Sambucus canadensis under salinity and alkalinity stress,salinity and alkalinity resistance of this plant roots was measured by electrical impedance spectroscopy （ EIS ） and electrolyte permeability methods and the estimation model of K Content of their roots was establish. [Method]The electrical impedance spectroscopy, cell membrane permeability and the change of K content in roots during different concentrations of salinity-alkalinity stress were studied. The corrections between EIS parameters and K content were analyzed using linear and nonlinear regressions. The estimation model was constructed using the best EIS parameter and the model accuracy was tested.[Result]During the salinity and alkalinity stress,compared with control,the K content of Sambucus canadensis roots treated by different concentrations of salinity-alkalinity significantly decreased（P≤0. 05）. As the extension of salinity-alkalinity stress time, the relative conductivity of the roots under different stress tended to rise and significantly increased compared with control （ P≤0. 05 ） . The spectra of electrical impedance changed in roots of Sambucus canadensis during salinity-alkalinity stress;The EIS parameter τ was the best for assessing K content of root. The best model was y =0. 005 5x3 -0. 232 8x2 ＋2. 638 8x ＋ 15. 877 with the precision accuracy of 91. 73%.[Conclusion]The model y =0. 005 5x3 -0. 232 8x2 ＋2. 638 8 x＋ 15. 877 with best precision accuracy constructed with EIS parameter τ can be used to fastly and accurately forecast K content in roots of Sambucus canadensis under salinity and alkalinity stress.