Determination of Lignin Distribution during Ageing of Bamboo Culms (Phyllostachys pubescens) with Visible-Light Spectrophotometry
YANG Shu-min1, JIANG Ze-hui1*, REN Hai-qing1, FEI Ben-hua1, LIU Xing-e2
1. Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China 2. International Center for Bamboo and Rattan, Beijing 100102, China
Abstract：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.
Key words：Moso bamboo;Distribution of lignin;Lignification;Visible-light microspectrophotometry
