禾本科叶片表皮结构细胞的组合式样及其分类学意义

利用光学显微镜,对禾本科204属373种植物的叶片表皮进行了观察。发现禾本科叶片表皮细胸细胞在下表面上的分布式样可以划分为5个基本类型,即竹型、稻型、黍型、虎尾草型和早熟禾型,而5个基本类型所附属的植物类群分别是禾本科中的竹亚科、稻亚科、虎尾草亚科早熟禾亚科。同时分析了这5个类型的演化水平,并同类群的外部形态、地理分布相印证,表明竹亚科最原始、稻亚科次之、黍亚科演化居中、虎尾草亚科较高级、早熟禾亚科最高级;禾本科可能起源于世界的热带区域。

COMBINATIVE PATTERNS OF CONSTITUENT CELLS OF LEAF EPIDERMIS OF POACEAE AND THEIR TAXONOMIC SIGNIFICANCE

The leaf epidermises of 373 species (belonging to 204 genera) of the family Poaceae were examined under light microscope. It is considered that in Poaceae the conbinative patterns of constituent cells on the lower epidermis of leaf bl ade may be devided into five major types, i. e. Bambusoid type, Oryzoid type, Panicoid type, Chloridoid type and Pooid type; and the taxa differentiated with the characters of the five types are Bambusoideae, Oryzoideae, Panicoideae, Chloridoideae and Pooideae. This result is in ngreement with the five subfamilies devided by authors according to the morphological difference of constituent cell, also similar to some subfamilies confirmed by our predecessors according to the external morphology. In the evolution, some distribution characters on the lower surface may be the most primitive in the family, for example, the stomatal apparatus are gathered in 2 - many rows on each side of the in tercostal zone, the microhairs are distributed between the veins, the papillae are distributed densely and the number on each long - cell is more, and so on; and others advanced or slightly advanced distribution characters, for instance, the stomatal apparatus are distributed in 1 ~2 rows on each side or in the middle part of intercostal zone,the microhairs are only distributed in the middle part of intercostal zone or are absent,the papillae are distributed sparsely and only one is borne on each long - cell or are absent, and so forth- On these grounds, the evolutionary level of the five types were discussed, and the relationships among them correspond to the external morphology and geographic distribution of taxa. The last results show that Bambusoideae is the most primitive in poaceae, Oryzoideae is slightly more advanced than the former, the evolutionary position of Panicoideae is intermediate in the family, Chloridoideae is more advanced than it, and Pooideae is the most advanced among the five subfamilies; the family Poaceae might originate from the World's tropical zone.