植物气孔原始形态—“前气孔”的发现

Discovery of stomatal original form-“prestoma”

为探究植物气孔(stomata)的起源演化,本文以槲蕨(Drynaria roosii)原叶体及幼孢子体的第一枚叶片、满江红(Azolla pinnata)孢子体叶片为材料,用扫描电子显微镜观察了各自的气孔及类似气孔的超微立体精细结构特征。结果表明槲蕨幼孢子体气孔有2个保卫细胞,满江红孢子体气孔仅有1个保卫细胞,而槲蕨原叶体上发现的类似气孔结构,由1个保卫细胞和中间的狭缝组成,不具有真正的孔,本文将其命名为前气孔(prestoma),并对前气孔的特殊性进行了分析,旨在为探讨陆地植物气孔起源及系统演化提供溯祖形态依据。

In order to explore the origin and evolution of the stomata,the prothallium and the first leave of young sporophyte of Drynaria roosiiand the leaves of sporophyte ofAzolla pinnata were taken as samples.The ultrastructure of stomata and stomata-likecomponents was observed by scanning electron microscope(SEM).The results showed that two guard cells were in the stomata of D.roosii,and one guard cell in the stomata of A.pinnata.However,thestomata-likecomponents on prothallium of D.roosiicontained a guard cell and a slit but no real pores.Thus,wenamed it the prestoma,and its particularity was discussed.Here,we provided the evidence with coalescent form for exploring the origin of land plants'stomata.