匍茎百合的细胞地理学分析

匍茎百合(Lilium lankongense)是青藏高原的一个特有百合物种。为了研究其核型特征以及不同居群间的演化关系,该研究采用常规压片法对8个居群的核型进行观察分析。结果表明:(1)8个居群的染色体核型均为3B型,染色体基数为12,核型不对称系数(As.K%)为81.28%~83.53%。(2)结合前人的研究表明,匍茎百合各居群在地理分布上沿着察隅县-茨中村-香格里拉市-木里县一线从西向东迁移、扩散的分布扩张,同时分布于贡山县至香格里拉市一线的居群在地理分布上还存在纬度上的向北和向南迁移、扩散的分布扩张态势。(3)该研究首次发现匍茎百合存在B染色体的情况,其B染色体对适应特殊生境具有重要意义,匍茎百合是一个正处于高度分化过程中的物种。

Cytogeographical Analysis of Lilium lankongense

Lilium lankongense is a unique species distributed in the Qinghai-Tibet Plateau.In order to investigate its karyotype characteristics and the evolution of different populations,we compared and analyzed the karyotypes,which included 8 populations of L.lankongense,by chromosome routine tableting.The results showed that:(1)karyotypes were 3B,and the basic number of chromosome was 12 in the eight populations.The karyotype asymmetry coefficient(As.K%)of eight populations were 81.28%to 83.53%.(2)Combined with previous studies,it is shown that the geographical distribution of L.lankongense populations along the line of Zayü-Cizhong-Shangrila-Muli has migration and diffusion from west to east.At the same time,the populations,which distribute in the line from Gongshan to Shangri-la,have a geographic expansion of migration and diffusion in northward and southward in latitude.(3)This study found B chromosome in L.lankongense for the first time,and its B chromosome is of great significance for adapting to special habitats.L.lankongense is a highly differentiated species.