中国桑寄生科的孢粉学研究  

Pollen morphology of the Loranthaceae from China

作　　者：韩荣兰[1] 张奠湘[1] 郝刚[1] 

机构地区：[1]中国科学院华南植物园,广州510650

出　　处：《植物分类学报》2004年第5期436-456,共21页Acta Phytotaxonomica Sinica

摘　　要：系统报道了中国桑寄生科Loranthaceae 33种 5变种植物的花粉形态 ,并与澳大利亚 2属 6种植物的花粉形态做了比较。通过光学显微镜和扫描电镜观察 ,国产桑寄生科花粉外壁纹饰可明显分为两个类型 :一种类型为刺状或条状纹饰 ,另一种为颗粒状纹饰 ,这与该科的鞘花族和桑寄生族两个族相吻合。在鞘花族类型中 ,3合沟、钝刺状或条状纹饰的花粉是基本类型 ,合半沟或孔沟形 ,刺状纹饰的花粉是较进化的类型 ;在桑寄生族类型中 ,等极、3合沟、颗粒状纹饰的花粉是基本类型 ,异极、副合半沟_合半沟、3沟形和沟形_短沟形或沟孔形、粗糙或模糊颗粒状纹饰的花粉是较进化类型。根据萌发孔和纹饰可将桑寄生族类型花粉分为 3个类群 :类群I包括五蕊寄生属Dendrophtho 、梨果寄生属Scurrula、钝果寄生属Taxillus和大苞寄生属Tolypanthus;类群II仅包括离瓣寄生属Helixanthera ;类群III也仅 1属 ,桑寄生属Loranthus。在这 3个类群中 ,类群I属于基本的类型 ,属间花粉差别较小 ,其中梨果寄生属和钝果寄生属花粉差别最小 ,显示出较近的亲缘关系 ;Pollen morphology of 38 taxa of Loranthaceae from China, and of eight taxa from Indonesia and Australia was examined under light microscope (LM) and scanning electron microscope (SEM). Based on exine ornamentation characteristics, Loranthaceae can be subdivided into two groups that are consistent with the two tribes in the family: Elytrantheae and Lorantheae. In the tribe Elytrantheae, pollen grains with 3-syncolpate aperture and exine of blunt-tipped spines and striate ornamentation may represent the primitive type while those with diplocolporate and diplosyndemicolpate apertures are of derived nature. In the tribe Lorantheae, pollen grains with isopolarity, 3-syncolpate apertures, and granulate exine ornamentation may represent the primitive type, while those with heteropolarity, parasyndemicolpate-syndemicolpate, 3-colpate and colpate-brevicolpate or porate apertures, scabrate and indistinctly granulate ornamentation represent the derived state. Pollen data suggest three basic groups in the tribe Lorantheae according to the aperture and ornamentation characteristics: Group I is composed of Dendrophthoe, Scurrula, Taxillus, and Tolypanthus; Group II and Group III contain only Helixanthera and Loranthus respectively. Group I is relatively primitive in terms of pollen morphology. Among genera in Group I, there are only insignificant differences in pollen morphology between Taxillus and Scurrula, two genera with a close relationship; both Group II and Group III are relatively derived in terms of pollen morphology.

关 键 词：中国 桑寄生科 孢粉学 植物 花粉 萌发孔 

分 类 号：Q944[生物学—植物学]