The epidermal characters of mature leaves of 29 genera, 50 species and 3 varieties (totally 56 samples) representing all the 5 tribes in the family Menispermaceae were examined under the light microscope. The main conclusions are as follows: (1) The shape of the epidermal cells is polygonal or irregular, and the anticlinal walls are straight or waved in the family. In some genera a special arrangement of epidermal cells is named as “rosette-cell arrangement" for the first time. The lower epidermal cells were found to have a papilla in Stephania, Diploclisia and Legnephora . (2) In some genera, the anticlinal walls are oblique, rather than perpendicular, to the surface. (3) The stomatal apparatuses, generally restricted to the lower surface of the leaves, were assigned to anomocytic, staurocytic, cyclocytic, anisocytic and actinocytic types, and their distribution on the epidermis may be of diffuse pattern or island congregating pattern. (4) The cells of both upper and lower epidermis in the tribe Pachygoneae and Fibraureae are generally polygonal with straight or arched anticlinal walls, and the stomatal apparatuses are usually staurocytic and actinocytic. The cyclocytic stomatal apparatus was found only in two genera of the tribe Pachygoneae. By contrast, the epidermal cells of the tribes Anomospermeae, Tinosporeae and Menispermeae are generally irregular with waved anticlinal walls, and the stomatal apparatuses are predominantly anomocytic. These correlated characters are of much significance in delimiting tribes within the Menispermaceae, and also provide evidence for studies on systematic relationships of several genera.
防己科植物的叶表皮特征及其系统学意义
洪亚平* 潘开玉 陈之端** 路安民
(中国科学院植物研究所系统与进化植物学开放研究实验室,北京100093)
摘要:利用光学显微镜观察了防己科 2 9属 5 0种 3变种的叶表皮形态。结果表明 :(1)该科植物叶表皮细胞形状为多边形或不规则形 ,垂周壁式样为平直和波状缘 ;首次发现一些属的表皮细胞排列成玫瑰花环式样 ;在Stephania等属发现其下表皮细胞中央有乳突。 (2 )气孔器为无规则型、环列型、十字型、辐射型和不等细胞型 ,几乎均出现在下表皮 ,在表皮上的分布有散生和岛状聚集两种式样。 (3)在五族中 ,Pachygoneae族和天仙藤族的上、下表皮细胞多为多边形 ,垂周壁平直 ,气孔器多为十字型和辐射型 ;而另外三族的上、下表皮细胞多为无规则形 ,垂周壁波状 ,气孔器则以无规则型为主 ,这些相关性状对于科下族的划分具有重要价值 ,同时也为一些属的系统学关
关键词: 防己科;叶表皮;系统学意义
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