广西产四种竹材的比较解剖研究

THE COMPARATIVE ANATOMY OF FOUR BAMBOO CULMS IN GUANGXI

本文利用光学显微镜及计算机图像分析系统研究了广西产４种竹材马蹄竹、撑篙竹、车简竹、越南巨竹的解剖性质，其中包括表皮层、副表皮层、皮层、维管束、纤维、基本薄壁组织以及髓环等组织的结构特征。结果表明：４种竹秆的表皮细胞均为一层，副表皮细胞１－２层，竹秆横切面上维管束在单位面积内的数目以撑篙竹最多，平均为４．０８个／ｍｍ２，车简竹最少为２．０１个／ｍｍ２。导管直径由竹秆壁外侧向内逐渐增大，导管长度以竹秆壁中部最大，导管壁厚由竹秆壁外侧向内逐渐增大。纤维平均长度以越南巨竹最长，平均为 ２． ７２ｍｍ；纤维直径和壁厚最大，分别是撑篙竹（平均为１５．６８μｍ）和马蹄竹（平均为６．７２μｍ）。竹秆壁中输导组织所占比例以中部最多，如撑篙竹高达１２．１％；纤维组织在竹秆壁外侧最多，撑篙竹为６４．３９％。薄壁组织则以竹秆壁的中部和内侧较多，其中越南巨竹的薄壁组织以中部和内侧最多，分别占５９．７％和７４．７％，撑篙竹髓环细胞不特化为石细胞，马蹄竹髓环特化不明显，其余两种髓环细胞则高度特化。上述４种竹材的解剖特征与其物理机械特性及加工性质等均有密切关系，可为其开发利用提供重要依据。

The middle internode of four bamboo species culms from Guangxi autonomous region named Bambusa lapidea, B. sinospinosa, B. pervariabilis and Dendrocalamus yunnanensis were collected and cut. The bamboo section method,maceration technique and light microscope with computer image processing analysis system were used to investigate their anatomical structures, including epidermis, subepidermis, cortex, fiber and vascular bundle. The results showed that the number of vascular bundles per square millimeter across the bamboo culm wall was higher for B. pervariabilis (average 4.08),and lower for B. sinospinosa (average 2. 01). The diameter of vessel elements were larger gradually from the outer part to the inner part of the culm wall. The longest vessel elements were almost located in the middle part. The wall thickness of the vessel increased from the outer part to the inner part. The longest fiber of 2.72mm for D. yunnanensis,the largest cell diameter of 15.68μm for B. pervari abilis, the thickest cell wall of 6. 72 μm for B. lapidea. There were significant differences in the ratio of various tissue. Conducting tissue was the major element in the middle part of the culm, and B. Pervariabilis contained 12. 1% for such tissue, was higher than the other species. More fiber tissue was located in the outer culm wall, B. pervariabilis had the higher proportion of the fiber, average 64.39%, These anatomical properties provided the basic information for these four bamboos physical,mechanical and industrial utilization.