6种竹子叶器官的解剖结构比较

【目的】探究竹子营养叶与秆箨之间的关系，揭示竹子不同功能叶器官的结构差异，为竹类植物的基础生物学研究提供新的理论信息。【方法】以6种竹子即勃氏甜龙竹(Dendrocalamus brandisii)、慈竹(Bambusa emeiensis)、绵竹(Lingnania intermedia)、香竹(Chimonocalamus delicatus)、云南箭竹(Fargesia yunnanensis)和美竹(Phyllostachys mannii)的营养叶、秆箨和叶枝为研究对象，观察它们的显微结构，并对其各项指标进行测量与比较。【结果】竹子营养叶解剖结构具有指状臂细胞或梅花状细胞的分化，并且具有薄壁维管鞘细胞；秆上部的箨片形态更接近于叶片，而下部的箨片具有较厚的角质层，无叶肉细胞的分化，与叶片形态差异明显。竹子营养叶的叶片、叶柄、叶鞘和叶枝维管束韧皮部的面积占比均高于木质部，与秆箨(笋箨)有显著差异。秆箨(笋箨)的箨鞘与箨片维管束木质部面积占比更高，虽然秆上部箨片形状和大小都与叶片接近，但与叶片相比，其维管束木质部面积占比更高。叶鞘和箨鞘的解剖结构与叶片和箨片的有区别，与叶柄的结构基...

Comparison of anatomical structure of six bamboo species cotyledon organs

【Objective】 Bamboo leaf organs include vegetative (branches and leaves) and culm (culm sheath) leaves. To explore the relationship between vegetative leaves and culm sheaths, this study aimed to reveal the structural differences in different leaf organs of bamboo plants due to different functions, and provide new theoretical information for basic biological research on bamboo plants. 【Method】 This study used six bamboo species, namely, Dendrocalamus brandisii, Bambusa emeiensis, Lingnania intermedia, Chimonocalamus delicatus, Fargesia yunnanensis, and Phyllostachys mannii. The leaves, culm sheath, and leaf branches of six kinds of bamboo were used as experimental materials, differences in microstructure were observed, and their indexes were measured and compared. 【Result】 The anatomical structure of the leaves showed differentiation of finger arm cells or plum blossom-like cells in anatomical structure, and thin-walled vascular sheath cells were observed around vascular bundles. The sheath blades in the upper part of the culms were closer to the vegetative leaves in shape, whereas those in the lower part of the culms were shorter and thicker, with a thick cuticle and without apparent differentiation of mesophyll cells, which was significantly different from that of vegetative leaves. The ratio of phloem area to vascular bundle area of the leaf, petiole, leaf sheath and twigs was higher than that of xylem, which was significantly different from that of the culm sheath. The proportions of xylem area in vascular bundles of the culm sheath and culm sheath blades were higher, among which the sheath blades at the upper part of the culms were similar to the branch leaves in shape and size, but the proportion of xylem area in vascular bundles was higher. The anatomical structure of the leaf sheath and culm sheath was different from that of the leaf blade and sheath blade but was basically the same as that of the petiole. Moreover, the base of all branch sheaths or culm sheaths covered branches or axillary buds; therefore, it was considered that the sheaths should be a modified petiole. 【Conclusion】 The phloem was more developed in vegetative leaves, whereas the xylem was more developed in the culm sheath. This could be due to the fact that vegetative leaves mainly function in nutrient transport, whereas the culm sheath mainly functions in water transport. The cumulus sheath should be a modified petiole. In addition, the vascular bundles of all organs and tissues of bamboo showed that the phloem was in the adaxial direction of the vascular bundle, and the xylem was located in the adaxial direction of the vascular bundle.