芒秆皮层的SEM-EDXA研究(Ⅱ)

用SEM-EDXA法研究芒秆叶鞘皮层的形态、超微结构及Si等矿质元素的分布.结果表明,叶鞘外表面皮层由颗粒物纵向规则排列区域和分散分布区域交替排列而成;每个颗粒物组由两个相对的"肾型"颗粒物纵向排列而成.与外表面皮层两种形态区域对应,皮层横切面由致密区域和疏松区域交替排列而成;致密区域的厚度大且质地较均一,Si元素的含量低,其内部主要是维管束组织;疏松区域的厚度小,Si元素的含量高,其内部则主要是近乎圆形的空腔.叶鞘皮层主要含C、O、Si、Cl、K、Ca等元素,C元素的含量低;外表面皮层的Si含量约为50%,内表面皮层的Si元素含量仅4%左右;叶鞘外表面皮层中的Si化合物主要是无机物.

Study on the Cuticle of Miscanthus Stem by Means of SEM-EDXA (part Ⅱ )

The morphologies, ultra-structure of the cuticle of Miscanthus leaf sheath and the distribution of mineral elements in the cuticle were studied by means of SEM-EDXA. The results showed that the outer-surface of the cuticle consists of two regions alternatively, the regular and dispersive distribution of the granules. Each group of the granules is made of two opposite kidney-like granules arranged longitudinally. In correspondence with two different shapes of the outer-surface cuticle, the transverse sections of the outer-surface cuticle consist of two zones by turns, i.e. the thick, homogeneous one with lower silicon content, and the thin, loose one with higher content of silicon. The inner organ of the former zone is mainly the bundle tissue, the key organ of the vein. However, there is a big circular hole in the later zone. The cuticle of Miscanthus leaf sheath contains five major elements, i.e. C, O, Si, K and Ca, the silicon content in outer-surface cuticle is up to 50%, but that in inner-surface cuticle is about 4%. Most of silicides in afore mentioned cuticle are inorganic silicides.