中国马兜铃属植物的细胞分类学初步研究

A PRELIMINARY CYTOTAXONOMICAL STUDY ON THE CHINESE ARISTOLOCHIA(ARISTOLOCHIACEAE)

本文报道了中国马兜铃属１２种植物的染色体数目和核型分析，发现并确定了ｘ＝８为本属染色体基数之一。本属染色体的共同特征是：小型；以中部（ｍ）、近中部（ｓｍ）着丝点染色体为主；核型类型为１Ａ、２Ａ、３Ａ、１Ｂ、２Ｂ；随体一般处在染色体的长臂上。

This paper reports chromosome numbers and karyotype analysis of 12 Aristolochia species from China for the first time. The results are shown in Table 1 and 2.The general aspects of the chromosome of this genus are small in size, mostly metacentric and submetacentric, the secondary constrictions are nearly all on the long arms, karyotypes are 1A, 2A, 3A, 1B. 2B and considered as symmetric types.Besides the previously reported x=6、7, x=8 is suggested here as one of the basic number of the genus owing to the frequent occurrence of 2n=32 in Subgen.Slphisia. According to the karyotype analysis, species with 2n=32 seem to be allotetraploids.