千里光(菊科:千里光族)的核形态及其系统学意义

Karyomorphology of Senecio scandens(Asteraceae:Senecioneae) and its Systematic Implication

研究了千里光的核形态:染色体间期为简单型与复杂型的过渡型,前期染色体为中间型。染色体长度从2.96μm到5.36μm,平均长度为4.03μm,核型公式为:2n=20=12m+8sm(2SAT),为2A类型。从核形态分析,千里光处于进化中较稳定和较原始类型。

In this paper the karyomorphology of Senecio scandens is studied. The chromosome interphase is categorized as the intermediatet type between the simple chromocenter type and complex chromocenter type, and the mitotic prophabe chromosomes are chassified as the interstitial type.The metaphase chromosomes of this species are relatively large,ranging from 5.36 μm to 2.96 μm and the average length is 4.03 μm. The karyotype is formulated as 2n=20=12m+8sm(2SAT) and categorized as stebbin's 2A type. All this shows that the karyotype of Senecio scandens is stable and primitive in evolution.