可见光显微分光光度法测定毛竹发育过程中木素微区分布

运用光学显微镜和可见光显微分光光度计以及组织化学染色对毛竹发育过程中的木质素微区分布进行了研究。木质素在各组织中均有分布,其含量因竹龄,组织及细胞壁微区不同而有差异。细胞壁各微区中存在愈创木基(G)和紫丁香基(S)两种木质素组成单元。纤维次生壁,细胞角隅区和复合胞间层的木质素含量12个月内逐渐增加,而后变化较小,但是各微区的木质化速率因竹龄变化而变化。同一竹龄竹壁径向和纤维帽不同位置的木质素含量未有明显的规律性变化。薄壁组织次生壁,胞间层以及导管次生壁在12个月内木质化程度不断加强,而后变化较小。

Determination of lignin distribution during ageing of bamboo culms (Phyllostachys pubescens) with visible-light spectrophotometry

The lignin distribution in different anatomical regions of developing moso bamboo Phyllostachys pubescens f. lutea Wen was investigated by means of optical microscope and visible-light microspectrophotometry coupled with the Wiesner and Maule reaction. The lignin is widely distributed in different tissues, in which there is a difference in lignin content between different ages, tissues and anatomical regions. Guaiacyl lignin and Syringyl lignin unit can be found in cell wall of fibre, parenchyma and vessel. Lignin content of secondary wall, cell corner and compound middle lamellae of fibre increased gradually within 12 months, then almost remained in the same level or decreased slowly in the culms with an age from 12 to 78 months. The lignification rate in secondary wall, cell corner and compound middle lamellae of fibre changed with age until they reached a relative steady value. There is no regular variation in lignin content with different radial location of culms and different location in fibre strands within one age. The secondary wall, compound middle lamellae of parenchyma and vessel secondary wall lignified rapidly within 12 months, and then changed slowly.