须芒草族植物花粉形态的观察

OBSERVATION ON POLLEN MORPHOLOGY OF THE TRIBE ANDROPOGONEAE (GRAMINEAE)

摘要:

在光学显微镜下和扫描电镜下对禾本科须芒草族(Andropogoneae)中分隶于8个亚族34个属的36种植物的花粉进行形态观察和比较研究。结果显示,本族植物花粉形态较为一致,花粉近球形或扁球形,单萌发孔,孔周围加厚,具盖,外壁表面散布有颗粒。这表明其是一个自然类群。总体来讲,花粉没有大的演化分异,只是表面纹饰和花粉大小有一定的差异。纹饰可分为三种类型:粗糙型,不明显疣状突起型和明显疣状突起型.花粉形态在植物系统演化上有一定的参考意义。

Abstract:

Pollen morphology of 36 species in 34 genera belonging to 8 subtribes of the tribe Andropogoneae was examined and compared by means of light microscope and scanning electron microscope. Results reveal that the morphology of pollen grains in this tribe is mostly unanimous. The pollen grains are sub-spherical or ellipsoidal with a single operculate aperture surrounded by a raised rim. The surface of exine is interspersed with granules. All these show that it is a natural group. Except for some differences in exine ornamentation and pollen size，there is no great evolutionary divergence among genera in pollen morphology．Based on the ornam entation，the pollen grains in the tribe can be divided into 3 types，namely scabrous，obscurely verrucate and obviously verrucate，which is useful in the research of systematic evolution．