Confocal Raman microspectroscopy (CRM) is an important tool for analyzing the compositional distribution of cell walls in situ. In this study, we improved the sample preparation method using paraffin-embedded sections combined with hexane dewaxing to obtain high resolution Raman images. We determined that the cell wall components of fiber cells were different from those of ray cells and vessel cells in the xylem of Populus tomentosa. Acetyl bromide and CRM methods produced similar trends when the difference in lignin intensity in the xylem region was compared between transgenic PtrLac4 and wild-type P. tomentosa. However, CRM proved more useful to analyze the lignin distribution in each cell type and distinguished the detailed difference in lignin intensity at the cellular level. Thus, CRM proved to be a useful in situ method to rapidly analyze the spatial variation of lignin content in the xylem of woody plants.

共聚焦拉曼显微光谱 (CRM) 是原位分析细胞壁组成分布的重要工具。在本研究中，我们改进了使用石蜡包埋切片结合己烷脱蜡的样品制备方法，以获得高分辨率的拉曼图像。我们确定毛白杨木质部中纤维细胞的细胞壁成分与射线细胞和血管细胞的细胞壁成分不同。当比较转基因PtrLac4和野生型P. tomentosa木质部区域木质素强度的差异时，乙酰溴和 CRM 方法产生了相似的趋势. 然而，事实证明 CRM 更有助于分析每种细胞类型中的木质素分布，并在细胞水平上区分木质素强度的详细差异。因此，CRM 被证明是一种有用的原位方法，可以快速分析木本植物木质部木质素含量的空间变化。