报春苣苔属43种植物花粉形态及其分类学意义

Pollen Morphology of the Primulina(Gesneriaceae)from South China and Its Taxonomic Significance

采用扫描电镜观察了中国华南地区报春苣苔属43种植物的花粉形态,并对其花粉形态进行了聚类分析,基于孢粉学聚类结果,并结合形态学特征以及供试物种的地理分布特征,从多个角度联合探讨其分类学意义。结果显示:(1)报春苣苔属43种植物花粉粒为较小到中等大小类型,均为三沟花粉粒;花粉粒形状从圆球形到超长球形,以长球形为主要形态;花粉粒极面观形状为圆状三角形、圆形和3裂圆形;外壁纹饰均为网状纹饰,绝大多数为宽网脊。(2)孢粉学聚类结果将43种植物划分为6个组7个类型,初步表明该属植物的花部大小和颜色是多起源进化而来的,根据分布区域的比较,该属的物种形成可能和适应华南喀斯特特殊地貌与小环境的形成有密切关系。

Pollen grains of 43 species of the genus Primulina from South China were observed under a scanning electron microscope. The morphological variability of pollen and the taxonomic implications of pollen morphology were observed,in addition,the result of cluster analysis（UPGMA）was performed on the palynology data and reported here,showing：（1）Pollen grains of Primulina were all tricolpate,sexine ornamentation all were reticulate,while the distinction exists in size,shape and exine sculpture among different species.（2）Cluster analysis resulted in the delimitation of six main subclusters with seven groups,the result showed that the great morphological hetero-geneityis in the genus is polyphyletic;And through combine,comparative analysis and species distributions,indicates that the developing and forming of karsts physiognomy in South China played an important role in the taxa differentiation of Primulina.