Studies on the Stiffness of Culms in Barley Plants (Hordeum sativum, JESSEN) : 13. Histochemical observations on the thickness-part in the nodes.

摘要

It is the purpose of this study to clarify the histochemical features of the thickness-part in the nodes. The thickness-part in the nodes is composed from two parts, i. e. the leaf sheath and culm. The leaf sheath tissues are kept in healthy condition with out any disorganization of tissues, so the stiffness of these parts may be considered to be maintained by the nature of tissues. In the above mentioned two parts. It is the specific features of tissues of the leaf sheath that they consist of the sclerenchyma cells which are rich in cellulose and are lignified. In the tissues of the leaf sheath, the vascular bundles are positioned at the one side of the sclerenchyma. The sclerenchyma cells are rich in protoplasm, especially in upper nodes. The other hand, the specific features of the culm tissues are considered as follows; they are constituted of lignified sclerenchyma cell layer and lignified vessels. The dynamical properties for stiffness of the thickness-part in the nodes are superior than that in the internodes. Probably, these properties are due to the duality of the part, i. e. leaf sheath and culm.