长柄马兰(菊科)的形态补充描述及细胞学研究

Supplementary Description on Morphology and Cytology of Aster longipetiolatus C.C.Chang(Asteraceae)

结合模式产地采集的长柄马兰(Aster longipetiolatus C.C.Chang)标本以及查阅相关文献资料,发现已有的形态描述不充分且缺乏细胞学方面的报道。本研究对长柄马兰的形态特征进行补充描述和核型分析,为探讨其分类地位提供资料。结果包括:(1)发现并补充长柄马兰新的形态特征:花序托凸起、总苞片3~4层、舌状花具有退化雄蕊、舌片具柔毛、瘦果5肋。(2)细胞学结果表明,长柄马兰的染色体数目为2n=18,核型公式为2n=18=16m+2sm,核型属于1A。

The morphological description of Aster longipetiolatus C.C.Chang was inadequate in the original literature when compared with the specimen which we collected from its type locality,and there was a lack of cytological reports.The detailed morphological and cytological description of A.longipetiolatus were carried out,and the new evidences of plant taxonomical revision would be provided.The results showed that:(1)There were some newly-discovered characteristics for A.longipetiolatus.For example,the receptacle was convex,phyllaries3-or 4-seriate,ray floret staminodes,lamina pilosulose and achenes 5-ribbed;(2)Its cytology evidence revealed that the chromosome number was 2n=18 and the karyotype formulae was 2n=2x=16m+2sm,belonged to the type 1A.