采用光学显微镜对中国蓼属分叉蓼组(Polygonum section Aconogonon)和冰岛蓼属(Koenigia)的21种植物的叶下表皮微形态进行了观察研究。结果表明，其叶下表皮微形态特征可分为三种类型：（1）气孔器类型为无规则型，表皮细胞多边形，垂周壁为波状；（2）气孔器类型为无规则型兼有非典型不等型，表皮细胞为多边形或不规则形，垂周壁为平直弓形或波状；（3）气孔器类型为不等细胞型，表皮细胞多边形，垂周壁为平直弓形。分叉蓼组（西伯利亚蓼除外）植物的叶表皮气孔器类型具有高度一致性，说明该组是一个自然类群。本文研究结果不支持将大铜钱叶蓼(Polygonum forrestii Diels)、铜钱叶蓼(P. nummularifolium Meissner)划归于冰岛蓼属的处理意见；支持将西伯利亚蓼(P. sibiricum Laxm.)独立成属，即西伯利亚蓼属(Knorringia Tzvel.)的观点；同时也支持仍将多穗蓼(P. polystachyum Wall.ex Meissner)和松林蓼(P. pinetorum Hemsl.)归在分叉蓼组的处理意见。
The leaf lower epidermal characteristics of 21 species of Polygonum sect. Aconogonon and Koenigia from China were observed under light microscope(LM).Three main types of leaf lower epidermal micro-morphology could be recognized in the present paper;(1)The stomata are anomocytic; the shape of the leaf epidermal cells is irregular,and the anticlinal walls are undulate;(2)The stomata are anomocytic or nontypical anisocytic; the shape of the leaf epidermal cells is irregular or polygonal,and the anticlinal walls are straight to curved and undulate;(3)The stomata are anisocytic; the shape of the epidermal cells is polygonal,and the anticlinal walls are straight to curved.The present data indicated that the sect. Aconogonon is a natural group with highly uniform stomata.The results of this study didn’t support to ascribe P. forrestii Diels and P. nummularifolium Meissner into the genus Koenigia.The generic status of Knorringia is supported,and P. polystachyum and P. pinetorum should be retained in sect. Aconogonon.