昆明长虫山地区多星韭紫花与白花类型核型比较分析

Comparative Analysis on Karyotypes of Two Types of Allium wallichii from Mountain Changchong in Kunming Area

对昆明长虫山地区多星韭紫花和白花2种类型的核型特征进行了分析比较。结果表明:紫花和白花类型均为四倍体。白花类型核型公式2n=4×=28=8m(2sat)+20sm,最大染色体是最小染色体的1.64倍,着丝点端化值63.65%,核型类型属2A型。紫花类型核型公式2n=4×=28=10m(2sat)+16sm+2st,最大染色体是最小染色体的1.73倍,着丝点端化值64.35%,核型类型属2A型。2种类型的核型比较分析表明,尽管核型类型都属2A型,但紫花类型核型对称性与白花类型相比较小,提示白花类型为该地区的原始类型,紫花类型为次生类型。在紫花类型中发现了一定频率的结构变异类型,为紫花类型为次生类型的推测提供了细胞学证据。

Karyotypes of white flower and purple flower type of Allium wallichii from Changchong mountain were examined.The results showed that both types were tetraploid and the karyotypes types were 2A.The karyotype formula of white flower type was 2n=4×=28=8m（2sat）＋20sm,T.C.% was 63.65%;The karyotype formula of purple type was 2n=4×=28=10m（2sat）＋16sm＋2st,T.C.% was 64.35%.Comparative analysis on cytological characteristics showed the decline of karyotype asymmetry,which suggested the white flower type was the ancestral type,while the purple type was derived type in this area.Furthermore,one purple flower individual with chromosome structural rearrangement suggested the chromosome structural rearrangement was one of evolutionary source in Allium wallichii.