五味子科两个种的核型比较研究

本文报道二色五味子和盘柱五味子两种的染色体核型，均为首次报道．结果表明两种的核型公式相同，２ｎ＝２８＝２８ｍ，但根据Ｓｔｅｂｂｉｎｓ的核型不对称性的分类它们之间存在着明显的差异，二色五味子为１Ａ型；盘柱五味子为１Ｂ型。１Ｂ型是首次在被子植物中发现．也许它显示了原始类群中的一种进化特点。另外染色体相对长度组成表明二色五味子２ｎ＝２８＝１２Ｍ２＋１４Ｍ１＋２Ｓ；盘柱五味子２ｎ＝２８＝２Ｌ＋１２Ｍ２＋１２Ｍ１＋２Ｓ．由此南五味子属的核型较二色五味子进化。

COMPARATIVE STUDIES ON KARYOTYPES OF TWO TAXA IN SCHISANDRACEAE

The karyotypes of Schisandra bicolor Cheng and Kadsura longipedunculata Finet et Gagnep are reported for the first time. Both of them are 2n=28=28m,but there are significant differences in karyotypic types based on Stebbins karyotypic asymmetry. Schisandro bicolor belongs to Stebins 1A type; Kadsura longipedunculata belongs to 1B type, which is found for the first time in flowering plants. Perhaps it displays an evolutionary character in the primary group of angiosperm. In addition, the chromosome complement of Schisandra bicolor is 2n=28=12M2+14M1+2S; that of Kadsura longipedunculata is 2n=28=2L+12M2 +12M1+ 2S. Thus the karyotype of Kadsura is more advanced than that of Schisandra.