甘蔗茎秆细胞壁结构特征对维管束力学性能的影响  

Effect of Cell Wall Structural Characteristics of Sugarcane Stem on Its Mechanical Properties of Vascular Bundle

作　　者：刘庆庭[1] 李桃 林志超 黄吉雷 罗政和 黄瑶 LIU Qingting;LI Tao;LIN Zhichao;HUANG Jilei;LUO Zhenghe(College of Engineering,South China Agricultural University,Guangzhou,510642)

机构地区：[1]华南农业大学工程学院,广州510642

出　　处：《基因组学与应用生物学》2024年第7期1163-1171,共9页Genomics and Applied Biology

基　　金：国家自然科学基金项目(32271995)资助。

摘　　要：作物的茎秆由细胞-组织-器官等多尺度结构构成,维管束是茎秆的主要机械支持组织,细胞是最基本的力学承载单元,细胞的力学性能取决于细胞壁的力学性能和细胞的形态结构。细胞壁的结构特征(微纤丝角、晶体尺寸等)逐级影响到细胞、维管束和茎秆的力学性能,对细胞壁结构特征的研究可以为培育抗倒伏性状良好的品种提供参考。本文以甘蔗(Saccharum officinarum)品种‘桂糖49号’为研究对象,采用X射线衍射技术检测甘蔗茎秆维管束厚壁细胞壁微纤丝角,分析微纤丝角和晶体尺寸对甘蔗茎秆维管束力学性能的影响,以揭示甘蔗超微结构与宏观力学性能之间的内在关系。研究结果表明,在茎秆横断面上,从蔗皮到蔗芯厚壁细胞的细胞壁微纤丝角呈增大的趋势;沿茎秆纵向从基部、中部到梢部的厚壁细胞的细胞壁微纤丝角的变化不明显。茎秆单根维管束的拉伸弹性模量与微纤丝角呈负相关,相关系数r=-0.655;与纤维素晶体尺寸呈正相关,相关系数r=0.604。单根维管束的拉伸强度差异的43%是由微纤丝角引起的。Crop stems are composed of multi-scale structures such as cells,tissues,and organs.Vascular bundle is the main mechanical supporting tissue of the stem.Cell is the basic mechanical supporting unit.The mechanical properties of cells depend on the mechanical properties of the cell wall and the morphological structure of the cells.The structural characteristics of the cell wall affect the mechanical properties of the cell,vascular bundle,and stem step by step.The study of cell wall structure characteristics can provide a reference for breeding varieties with good lodging resistance.In this study,the microfibril angle of sclerenchyma cell wall of sugarcane(Saccharum officinarum)variety‘Guitang No.49'vascular bundles of sugarcane stems was tested by X-ray diffraction technology.The effects of microfibril angle and crystal size on the mechanical properties of the vascular bundles of sugarcane stem were analyzed.The internal relationship between the ultrastructure and macroscopic mechanical properties of sugarcane was studied.The results showed that in the cross section of stalk,in the direction from skin to core,the microfibril angle of sclerenchyma cells increased.Along the stalk from its base,middle to top the microfibril angle of thick-walled cell wall did not change significantly.The tensile elastic modulus of a single vascular bundle of the stem was strong negative correlation with the microfibril angle.Its correlation coefficient r=-0.655.The tensile elastic modulus was strong positive correlation with the cellulose crystal size.Its correlation coefficient r=0.604.About 43%of the difference in tensile strength of a single vascular bundle was caused by the microfibril angle.

关 键 词：甘蔗 维管束 细胞壁 微纤丝角 晶体尺寸 力学性能 

分 类 号：S566.1[农业科学—作物学]