【摘要】 似半环孔材;梯状复穿孔,横隔条数多;轴向薄壁组织星散聚合为主;射线组织异形Ⅰ型为主,2列射线占79％,多列射线融合成单列现象可见;细胞质及细胞核明显;结晶体菱形,仅见于方形或直立细胞。木材构造与柠檬黄金花茶Comellia limonia C.F.Liang et S.L.Mo相近似。更多还原

【Abstract】 Camellia terminalis J. Y. Liang et Z. M. Su, which was discoered in last year, is a new species of Sect. Chrysantha. The wood structure of this species was studied and was also compared, with the wood structure of other two species of the same Section. The result is as following.Like semi-ring porous wood. Vessels iregular polygons in cross section, 101-201 vessels per mm2, average 151. Perforation plates elliptic, scalariform perforation, branch of bars moderate to multiple (most 12-30). Axial parenchyma less, scattered. Parenchyma cells shorter, average 121, diam. 20μ, a quantity of cytoplasm in the cell cavity. There are nuclei in some parenchyma cells, oblong, always inclined to side of cell, and some nuclei are vanishing, no crystal appearance. Rays less, 6-8 rays per mm in cross section, average 33 rays per mm2 in tangential section, 2-seriate 79%. Heterogeneous rays, essentially type II. Crystal cells neither enlarged nor chambered, crystals rhomboid, bigger, almost occupied the cavity, but only exist in square ray cells.The wood structure of C. terminalis very close to C. limonia and differt from C. pingguoensis. The differences between C. lerminalis and C. limonia are as following: The heterocellular ray types I and I mainly in C. terminalis, types I and I mainly and without type I in C. limonia; with 4% of 3-seriate rays in C. terminalis only and 18% in C. limonia; nucleus none or occasionally solutive in longitudinal parenchyma in C. terminalis, but conspicuously in C. limonia; the nuclei conspicuous in rays cells of C. terminalis and less in C. limonia; in rays and longitudinal parenchyma, there are weak colour and sparse cytoplasm in C. terminalis, while in C. limonia with deep colour and plentiful gum. There are obvious differences between C. terminalis and C. limonia.There are cytoplasm and nuclei exist in mature wood of species of the Sect. Chrysantha. In spite of Necensany described in 1966, that the ray parenchyma or longitudinal parenchyma, at least in sap wood (even in heart wood) exist living protoplasm. MacDougal and Smith showed (1927) that in the wood of Sequoia semper-virens (Lamb.) Endl. living substance still in the ray parenchyma cells for more than 100 years. There are a few references on nucleus appearing in wood domestically, probably it has not been given sufficient notice. Therefore the discovery of nuclei and protoplasm in matured wood of Camellia Section Chrysantha is much value in scientific research.The functions of these nuclei showed by Nedesany, through the moving of the protoplasm of the living cells, the food in the cells are being transported and stored in wood parenchyma. Because plants of Camellia Section Chrysantha are almost shrubs or small trees, and with not enough solar light since long time living under forest, the physiologic function is not vigorous. These nuclei exercised to help the normal transportation or storage in those parenchma cells, to hold their regular physiologic functions. For the principle, the nuclei appeared in the matured wood of Camellia Section Chrysantha belong to nutrient nuclei.更多还原