中文摘要：

铁皮石斛是我国传统的中草药，多糖含量是衡量其品质优劣的一个重要指标。主要研究铁皮石斛多糖含量与光谱间的关系，旨在寻找铁皮石斛多糖含量的无损检测方法。研究方法：实验材料选自不同处理铁皮石斛组培苗和不同生长阶段的驯化苗。其中36个样本作为建模样本建立模型，11个样本作为检验样本对模型进行检验。分别采用偏最小二乘回归法和因子分析法建立样本光谱与多糖含量间的关系。结果表明：（1）光谱一阶微分与多糖含量的相关性优于光谱反射率，其中对多糖含量较敏感的波段主要集中在可见光区域。（2）偏最小二乘回归法的模型决定系数最高，但其预测能力较差。因子分析法模型具有较好预测能力，基于光谱反射率因子分析模型和基于光谱一阶微分因子分析模型的相对分析误差分别为2．269和2．305。

英文摘要：

The obj ectives in the present paper were to study the relationship between the polysaccharide content and the spec-trum,aimed at finding a non destructive testing method for the measurement of polysaccharide content.Materials in this study were from tissue culture seedlings under different treatments and domesticated plants in different growth stages.In the study,36 samples were used to build estimation models and another 11 as test samples to examine the models.The relationship between the spectrum and polysaccharide content was investigated by partial least squares regression （PLSR）and factor analysis.The re-sults show that （1 ）there was stronger correlation between derivative reflectance and polysaccharide content,and the sensitive wavebands mainly concentrated in the visible region.（2 ）The PLSR model has a high precision,while its prediction accuracy is lower.The models of factor analysis have higher prediction accuracy,the RPD of the model based on spectral reflectance is 2. 269 and that of derivative reflectance is 2. 305.