五节芒茎秆微观构造及结晶度研究

Microstructure and crystallinity of the Miscanthus floridulus culm

为更好地研究和利用五节芒Miscanthus floridulus茎秆,并为五节芒工业化利用奠定基础,研究了五节芒茎秆微观构造及茎秆去髓原料的纤维素相对结晶度。结果表明:五节芒茎秆皮部为茎秆最外层不含维管束的部分,木质部为皮部内圈维管束较多且紧密分布的部分,髓部为茎秆中部呈白色、含少量维管束的部分。茎秆表皮层由表皮膜、长细胞、短细胞和气孔器构成,长细胞长边边缘多呈锯齿形,且长、短细胞内含硅质。维管束由木质部、韧皮部、纤维细胞组成。原生木质部含环纹导管或螺纹导管。后生木质部的导管类型有网纹导管和孔纹导管。基本组织薄壁细胞主要特点是壁薄,壁上有纹孔,且内含淀粉粒。五节芒去髓茎秆梢部纤维相对结晶度为43.21%,中部为42.08%,基部为44.49%,基本相似,没有表现出明显的规律性。

The microstructure and crystallinity of the Miscanthus floridulus culm was studied to improve the research quality,to find possible new uses,and to lay a foundation for its industrial use.Results showed that the M.floridulus cortex was the portion of the outermost layer without vascular bundles,the xylem was the portion of the inner ring with comparatively more and closely distributed vascular bundles,and the pith was the portion of the central white culm with few vascular bundles.The culm epidermis were made up of epidermal membrane,long cells,short cells,and stomatal apparatus.Long cells were mostly serrated alongside the long edge.And the long and short cells containing silica.Vascular bundles were comprised of xylem,phloem,and fiber cells.Protoxylem contained circular grain vessels or spiral grain vessels,whereas metaxylem contained woven grain vessels or pitted vessels.The main features of the basic parenchyma cell tissue were thinwalls with pits and starch grains.The relative crystallinity of M.floridulus without pith for the upper culm cellulose was 43.21%,for the central part was 42.08%,and for the lower part was 44.49%.Thus,relative crystallinity was similar and did not show obvious regularity.