植物根—茎过渡区的研究现状

The Present Conditions of Research of Root-stem Transition Region

根—茎过渡区的研究对于双子叶植物的结构(初生维管系统)是极具证明力的.尤其是在系统发育和个体发育上有十分重要的意义.当前在国际上对幼苗初生维管系统根—茎过渡区的研究有两大学派,一派主张根的外始式星状中柱最原始,茎的内始式真中柱最进化,在两者之间存在一个下胚轴为中始式的根茎过渡区;另一派主张幼苗可分成根—下胚轴—子叶与上胚轴苗等两个单位,上胚轴常似成一种分离的结构,着生在根-下胚轴—子叶的单位上,根和上胚轴间不存在过渡情形.

The study of the root-stem transition region is very important for the structure of the double cotyledons plants. Especially for the system growth and individual growth. Today there are two important theories in the world about the root-stem transition region .One is the traditional theory. The other theory holds the view that the structure divide into three parts, which are the epicotylary shoot zone, cotyledon node zone and hypocotyl root zone.