中国拳参属(蓼科)植物叶脉序式样的研究

Leaf-Venation Patterns of Bistorta(Polygonaceae) in China

用清净标本制作法对中国产拳参属(Bistorta)(蓼科)12种1变种植物的叶脉序式样在光镜下进行了比较研究.结果表明,叶脉序式样可分为3种类型:(1)环结曲行羽状脉,边缘末级脉不完全,加粗且外卷;(2)环结曲行羽状脉,二级脉与其余各级脉近等粗,边缘末级脉具边脉,不加粗;(3)直行羽状脉,盲脉无或偶有,边缘末级脉不完全,不加粗.依据叶脉序式样,结合其植物习性及外部形态特征,将拳参属植物划分为3个组:拳参组sectionBis-torta,乌饭树叶蓼组sectionVacciniifoliaF.Z.Li,L.X.Liu&Y.T.Hou,sect.nov.和匍枝蓼组sectionBambu-phyllumF.Z.Li,L.X.Liu&Y.T.Hou,sect.nov..

Cleaning specimen preparation was adopted to comparatively examine the leaf venations of 12 species and one variety of Bistorta（Polygonaceae） in China and it was found that the leaf venations could be divided into three types, （1） brochidodromo-camptodromo-pinnate venation with imperfect, thickened and revolute marginal ultimate veins; （2） brochidodromo-camptodromo-pinnate venation with non-thickened marginal veins whose secondary veins were nearly as thick as those of higher orders; （3） craspedodromo- pinnate venation having veinletes or no veinletes present, and imperfect maginal ultimate veins. Bistorta plants could be divided into three groups according to their leaf venations, living habits and morphologies which are Bistorta section,Vacciniifolia F. Z. Li, L. X. Liu ＆ Y. T. Hou nov. section and Bambuphyllurn F. Z. Li,L. X. Liu ＆ Y. T. Hou nov. section.