三倍体毛白杨纤维形态学参数及木质素微区分布的研究

STUDIES ON FIBER MORPHOLOGY AND LIGNIN DISTRIBUTION OF THE TRIPLOID OF POPULUS TOMENTOSA CARR.

利用显微镜技术对三倍体毛白杨(triploidofPopulustomentosaCarr.)各部位的纤维形态学参数进行了测定。发现其纤维平均长度较长,长度分布均一,纤维的长度、宽度、壁厚等项指标最优值都集中在中部,梢部最差。用扫描电子显微镜(SEM)、SEM EDXA、透射电镜观察(TEM)技术重点研究了三倍体毛白杨超微结构及木质素的微区分布,结果表明超微结构属典型的分层结构,细胞壁分为胞间层(ML)、初生壁(P)、次生壁外层(S1)、次生壁中层(S2)、次生壁内层(S3),特点是S1层较薄、S2层厚、S3层很薄甚至不明显。木质素在各形态区中的分布是不均一的,其密度大小依次为细胞角隅(CC)>复合胞间层(CML)>次生壁中层(S2)。

Fiber morphological properties of the triploid of Populus tomentosa Carr.were analyzed in this paper.It was known that morphological parameters of each part of the wood are of little difference.Fiber average length is 0.97 mm.Length/width ratio and Runkel ratio of the middle of trunk are superior to other part of trunk.Ultrastructure and lignin distribution in the cell wall were mainly studied by using SEM and TEM with their accessory tools and techniques.The results indicated that cell wall is typically composed of middle lamella(ML),primary wall(P),outer layer(S1),(middle) layer(S2) and inner layer(S3) of the secondary wall.Furthermore,lignin distribution in the middle lamella and cell wall of wood fiber has been found to be quite heterogenous.Lignin concentration in the cell wall is in the (order) of:cell corner(CC)>compounded middle lamella(CML)>middle layer of the secondary wall(S2).