Anatomical Study Of Allotype Internode Formation Of Pseudosasa Japonica Var. Tsutsumiana

Pseudosasa japonica var. tsutsumiana is a stable variant of Pseudosasa japonica. In thispaper, the plant anatomical and statistical methods were applied to comparatively investigatebetween P. japonica var. tsutsumiana and P. japonica, including stem morphology structure,shoot bud’s development process, bamboo anatomy and fiber configuration. The main findingsare as follows:1. Compared with P. japonica, P. japonica var. tsutsumiana has a significantly shorterinternode length, and vase-shape because of internode base enlargement. The average full-heightand internode diameter of P. japonica is greater than that of P. japonica var. tsutsumiana.2. The shoot development process of P. japonica var. tsutsumiana and P. japonica can bedivided into five phases: dormancy period, germination period, pre-development period,mid-development period and late developmental period. During the whole development process,two bamboos nearly remain the same in both external shape and internal structure. Beforebamboo shoot being out of the earth, there is no obvious intermode elongation growth, P.japonica var. tsutsumiana’s intermode varation cannot be seen in shape and structure.3. P. japonica var. tsutsumiana and P. japonica don’t differ in epidermis, corte andsubcutaneous layer, but the basic organization appears a very clear distinction. Looking from thelongitudinai section, the basic organization of P. japonica is composed of long cells and shortcells, and the cells strictly arrange in the axial direction. But the basic organization of P.japonica var. tsutsumiana don’t have long cells and short cells, And the cell morphologywithout rules, The cells arrangement also have no rules both in the axial and lateral direction.4. The vascular bundles in culm of P. japonica var. tsutsumiana and P. japonica can beclassified in two types: the opening and semi-opening types. Vascular bundle size, the ratio oflength to width, density, and the diameter of the vessel varies with the different drawn parts. Ingeneral, after comparison of every vascular indicator in the same part, P. japonica var.tsutsumiana’s density is greater than P. japonica’s, while P. japonica’s vascular length-widthratio and vessel diameter is larger than P. japonica var. tsutsumiana’s. However, theirdivergences are not distinguished.5. In some parts of P. japonica var. tsutsumiana’s stem, its vascular bundles varies.According to the cell location and cell morphology, we conclude that such specific cell types arevariations of the fiber cells, whose mechanism and the law of variation still calls for furtherinvestigation.6. After comparison in bamboo fiber morphological characteristics, it is found that P.japonica fits for high quality paper’s raw material, and the length of P. japonica fiber is longer than that of P. japonica var. tsutsumiana, while their fiber width observes oppositely.Then to compare internode enlargement with not enlargement section for the same P. japonicavar. tsutsumiana, we found that fiber length in internode enlargement section is slightly shorterthan that of in not enlargement, fiber width in internode enlargement section is slightly largerthan that of in not enlargement section. Nevertheless，the fiber morphology index has nosignificant difference between internode enlargement and not enlargement section.