我国睡莲科花粉形态的研究

本文对我国睡莲科5属11种2变种的花粉形态进行了系统的研究。每种花粉都通过光学显微镜和扫描电镜进行观察和照相。同时对莲和白睡莲二种花粉作了超薄切片,对它们的外型结构进行了透射电镜的观察和照相。并结合有关分类学和孢粉学资料,讨论了本科的原始性、异质性及演化上的问题。

STUDIES ON THE POLLEN MORPHOLOGY OF NYMPHAEACEAE OF CHINA

There are five genera of Nymphaeaceae in China:Nelumbo, Brasenia, Euryole, Nymphaea and Nuphar. Pollen morphology of 2 varieties, 11 species representing 5 genera was examined under light microscope and scanning electron microscope. The structure of exine of Nymphaea alba and Nelumbo nucifera was also examined under transmision electron microscope. According to the type of aperture, it may be divided into three types:(1) Anasulcate type, Brasenia, Euryale and Nuphar. Pollen grains long ellipsoidal and ellipsoidal in polar view, and boat-shaped in equatorial view. Ornamentation of exine granulate in Byesenia, spinulate in Euryale and long spinate in Nuphar. (2) Zonasulculate type:Nymphaea. It may be subdivided into anazonasculate and zonizonasculate type. Pollen grains circular in polar view, and circular or subcircular in equatorial view. Ornamentation of exine tuberculate, granulate or spinulate. (3) Tricolpate type:Nelumbo. Pollen grains subcircular in polar view, and subcircular or ellipsoidal in equatorial view. Ornamentation of exine rough granulate under light microscope, but rugulate under scanning electron micro-scope. The structure of exine Nymphea alba and Nelumbo nucifera were examined under transmision electron microscope. The former has a granular structure with more or less homogeneous granules, but the latter a collumellar structure. According to the idea about the evolution of pollen grains in primitive Angiosperms proposed by Walker, the type of granular structure is a primitive type, and that of collumellar structure a advenced one. A number of taxonomists have considered that Nymphaeaceae is a primitive and heterogeneous family. On the basis of the pollen morphology of this family, it may be supported for this view-point. The evolutionary relationships among the pollen grains in this family was also discussed.