中国荩草属叶片表皮的微形态及其分类意义

本文报道荩草属及其邻近属共5属17种4变种的叶片表皮微形态研究,其中有些种类为首次报道。主要有以下几点: 1、荩草属叶片表皮微形态有5种类型,根据这几种类型结合小穗的外部形态,可在荩草属下分为两亚属及5个组。 2、荩草属及其哑铃形的硅细胞及三角形或圆屋顶形的气孔副卫细胞等近似须芒草属Andropogon Linn.应位于禾本科Gramineae蜀黍族Andropogoneae下,但硅细胞多为短哑铃形而且伴有其它各种类型,微毛的顶细胞远长于基细胞的独特性状,应独立成为荩草亚族Arthraxoninae Benth。 3、根据A.breviaristatus Hack.,A.quartiniana A. Rich.,A.pauciflorus Honda and A.hispidus(Thunb.)Makino 4者叶片表皮细胞类型完全相似特征,赞同P.C.van Weltzen意见,应作一种处理;根据国际命名法规优先律,应用A.hispidus (Thunb.) Makino。 4、海南荩草A. hainanensis Keng et S.L.Chen与茅坪荩草A. maopingensis S.L.Chen et Y.X.Jin应当独立成种.因其两种的叶片表皮细胞类型完全不同。

LEAF EPIDERMIS OBSERVATION ON GENUS ARTHRAXON (GRAMINEAE) FROM CHINA AND ITS TAXONOMICAL SIGNIFICANCE

This paper deals with the leaf epidermis of 17 species and 4 varieties, of Genus Arthraxon Beauv. and its relative genera from China, some species are reported for the first time. The results are summmarized as follows:1.There are 5 types of leaf epidermis in Chinese Arthraxon Beauv. According to these characters connected with gross morphology of sessile spikelets, we attempted to suggest two subgenera and five sections in this genus.2.Gen. Arthraxon Beauv. is similar to Gen. Androgon Linn, by the dumb-bell silica-cells and triangular or domeshaped subsidiary cells etc., hence it belongs to tribe Andropogoneae Ascherson & Graebner, but it should be as an independent subtribe Arthraxoninae Benth. by its short dumb-bell] silica-cells usually with cross-shaped or nodal-shaped together and the micro-hairs with length of distal cell much longer than the basel one.3.According to the characters of leaf epidermis of A. quartinianus A. Rich., A. pauciflorus Honda, A. breviaristaus Hack, and A. hispidus (Thunb.) Makino, we follow the opinion of P. C. van Welzen to arrange them as one species and according to the priority of International Code, it should be as an A. hispidus (Thunb.) Makino.4.A. hainanensis Keng et S. L. Chen and A. maopingensis S. L. Chen et Y. X. Jin should be considered as two separate species by their different characters of leaf epidermis.