【作者】 杨赵平；

【导师】 杜凡；

【作者基本信息】 西南林学院 ， 植物学， 2005， 硕士

【摘要】 镰序竹属Drepanostachyum Keng f．与悬竹属Ampelocalamus S．L．Chen et al．同属禾本科Poaceae竹亚科Bambusoideae Nees北美箭竹超族Arundinarieae Nees，共22种，我国就有18种，主要分布在我国西南三省、海南岛和台湾。两个属的多数种类外部形态十分相似，且大多数生长在石灰岩地区的沟谷河边或陡坡上，属内的羊竹子D. saxatile(Hsuch et Yi)Keng f.. ex Yi、巴竹D. yongshanense(Hsueh et D. Z. Li.)Yi、冕宁镰序竹D. mianningense(Q. Li et X. Jiang)Yi至今还没有发现花序，以至有些学者建议将它们归入悬竹属，而一些人则认为应纳入镰序竹属。针对形态上的困难，研究了镰序竹属与悬竹属13个种的根、叶的横切面及叶表皮的解剖结构，从所得的解剖结果探讨了镰序竹属与悬竹属解剖结构上的关系，并确定了羊竹子、巴竹、冕宁镰序竹的归属。主要研究结果如下： (1) 解剖了爬竹Drepanostachyum scandens(Hsueh et W. D. Li)Keng f.. ex Yi、羊竹子、射毛悬竹A. actinotrichus(Merr. et Chun)S. L. Chen, T. H. Wen et G. Y. Sheng等10个种的根。10个种根的外皮层、内皮层、中柱鞘细胞、纤维组织细胞的层数都较一致，这些特征与大多数散生竹的特性更接近，说明这2个属的竹子亲缘关系近，是丛生竹中较进化的类型。多数种的后生大导管、气腔数目和大小以及中柱髓部加厚情况在同一种类的不稳定性表明后生大导管、气腔都在根的生长发育过程中不断变化，根的内部解剖结构不能作为这两个属之间及属内各种的分类依据。 (2) 叶的横切面上，13个种的叶肉细胞形状一致，为指状臂形。叶片中部主脉的维管束数在同一种内常不稳定。泡状细胞的形状和数目变化较大，有些种，如爬竹、坝竹的泡状细胞在近主脉处只有2—3个泡状细胞，而在近叶缘的一边有5个，甚至7个以上的泡状细胞。射毛悬竹和勐腊悬竹A. menglaensis Hsueh et F. Du叶肉细胞的层数都是2层，另外11个种的叶肉细胞常为3层。射毛悬竹与勐腊悬竹的气腔在叶肉中所占的比例明显较另外11个种大，长度一般在128μm以上，宽度在10μm以上；其它11个种的气腔宽度大于10μm以上的气腔常常仅位于主脉旁，侧脉旁气腔的宽度都在10μm以下。扫把竹的气腔明显较小，气腔长度不超过56μm，且在近叶缘处的几个维管束旁没有气腔。 (3) 13个种叶的上、下表皮中长、短细胞的形状，大毛、刺毛、微毛、乳突的分布情况、气孔密度及气孔副卫细胞横向外侧壁等特征在同一个种间较稳定或仅在一定的范围内变化，是一些种很好的分类依据。射毛悬竹和勐腊悬竹在叶的上、下表皮各细胞的分布特征都较一致，尤其表现在刺毛和微毛的分布特征。比较叶横切面上的解剖结构，射毛悬竹和勐腊悬竹应该是同一类群的植物，属悬竹属。更多还原

【Abstract】 Drepanostachyum Keng f. and Ampelocalamus S. L. Chen et al. belong to Arundinarieae Nees, Bambusoideae Nees, Poaceae. They altogether have 22 species and there are 18 species distributing in Taiwan,Hainan and the three provinces in Southweast of China. Most of species of the two genara have similar morphology and distribute in valley or steep slope of limestone areas. we have not found the flowers of some species, such as, D.saxatile (Hsueh et Yi) Keng f. ex Yi, D.yongshanense (Hsueh et D.Z. Li.) Yi, D. mianningense (Q. Ii et X. Jiang) Yi. So some scholars attribute the three species into Ampelocalamus and others play them into Drepanostachyum. Considering the difficulty of morphological taxonomy, we study the anatomy of roots and leaves of 13 species of the two genara. On these ground, we analyze the anatomical relationship of the two genara and definite the systymatic position of D.saxatile, D.yongshanense and D. mianningense.Our main results as followed:(1) The anatomy of 10 species’roots was done. Their exodermises, endodermises, pericycles and the layers of fiber near exodeermise are very similar. All these morphologies are more close to those of scattered bamboos. Therefore, the relationship of the two genera is very close and they are more advanced than other clustered bamboos. The instability of the vessels of Metaxylem, air cavities and the piths in the cross section of roots shows all these are varying in the couse of root growing. in a word, the anatomical structures of theroots can not provide with the taxonomic proofs of Drepanostachyum and Ampelocalamus.(2) In the cross section, the mesophyll cells of 13 species is similar and all look like arm-cells. The number of vascular vundle of the midrib in one species is not the same.The shape and the number of the bulliform cells vary much. For example, in some species such as, D.scandens and D.microphyllum, there are only 2 to 3 near to the midrib, while there are 5 even more than 7 ones on the side of leaf verge. Except that the mesophyll cells of A.actinotrichus and A. menglaensis only have two layers, that of other eleven species often have three layers. Of the A.actinotrichus and A. menglaensis, the percent of the air cavities to the mesophyll cells is larger than that of other eleven species and the air cavities are often longer than 128μm and wider than 10μm, while in other eleven species the air cavities wider than 10μm.appear only near the midris and the width of the air cavities near lateral veins are all less than 10μm. It is obvious that the air cavities of D. fractiflexum looks much smaller. Its length is no more than 56μm and even there are absent beside some lateral veins near the leaf verge.更多还原