锦鸡儿属三个近似种区别特征的重叠和这种重叠在其花粉形态上的表现

Overlaps in Diagnostic Characteristics of Three Affinity Species of Caragana Fabr. and Responds of the Overlaps on Pollen Morphology

本文用扫描电镜首次在个体水平上观察了锦鸡儿属三个近似种的花粉形态。而且,对该三种植物的区别特征和分布进行了分析和研究。结果发现:该三种的宏观区别特征有一定的重叠和连续,在其花粉形态上也有相应的重叠,但宏观形态的重叠并不和花粉形态上的重叠密切相关。另外,三个种的分布有一个交叉区,在该交叉区内它们的区别特征发生相互交叉和重叠。对该三种的区别特征、花粉形态和分布的研究表明在该三种下面再成立种下类群是没有必要的。Caragma pygmaea 和C. stenophylla的花粉形态在种内的变异,特别在外壁纹饰、大小和形状等方面要比我们所想象的明显的多。本文还探讨了研究花粉形态在种内变异的意义和必要性。

Pollen morphology of 8 individuals that succumb respectively to three affinity specles of Cara gana Fabr. were investigated through the use of a scanning electron microscope firstly. For comparison, the diagnostic characteristics of these apecics and their distribution were analyaed, the results showed some overlaps and continuties in the diagncstic characteristics on macromorphology. Some overlape in pollen morphology of three apecice were also examined. On the other hand, the distribution of three apecies have a common area where they overlap in their characteristics. The intraspecific variation in pollen morphology, especially exine ornamentation, size and shape of some species is more remarkable than has been thought previously. However, that of C. leucophloca is not striking based on our observa- tion. In addition, the significances of intraspecific variations of pollen morphology were discussed in the paper.