蓼科花粉外壁超微结构的研究

Studies on pollen exine ultrastructure of the Polygonaceae

用扫描电镜和透射电镜对蓼科 6属 1 5种的花粉壁构造的特点进行了观察和研究。结果表明 :( 1 )外壁纹饰有如下几种 :颗粒 穿孔 ,微刺 穿孔 ,微刺 穿孔 光滑 ,颗粒 穿孔 光滑 ,细网状 ,粗网状 ,皱块状 ,鼓锤状 ;( 2 )外壁结构分化成两个明显的层次 ,即外壁外层以及外壁内层。其外壁外层由覆盖层、柱状层和基层组成。然而 ,由于每一部分发育状况的不同而导致外壁结构有各种变化 ,如无覆盖层或无外壁内层。

Pollen grains of 15 species representing 6 genera in the Polygonaceae were examined under scanning electron microscope(SEM) and transmission electron microscope(TEM). The results are summarized as follows: (1) The ornamentation of exine is granulate perforate, microechinate perforate, microechinate perforate smooth, granulate perforate smooth,finely reticulate, coarsely reticulate, or rugulate, granulate. (2) Under TEM all of the taxa examined generally have the exine stratification typical of the dicots: tectum, columellae, foot layer and endexine, although differences in the development of each of these units have resulted in variation in the exine structure.