摘要
百合科Ｌｉｌｉａｃｅａｅ葱属Ａｌｉｕｍ的宽叶组Ｓｅｃｔ．Ａｎｇｕｉｎｕｍ包括５种３变种。通过对该组的５种１变种的２３个地方居群的研究，得出以下结果。（１）宽叶组植物的染色体基数为８，核型类型一致，为２Ａ型，染色体类型以及不对称系数都很相似。核型特征的共性表明该组是一个自然的分类群。（２）虽然总体上组内的核型表现出较大的相似性，但在种间和种内各居群间也存在一定的差异。主要表现为：有的种内存在染色体的倍性变化；Ｂ染色体的有无以及数目和形态，在种内不同居群间存在变化；随体染色体上衔接随体的有无，在种间及种内都表现出多态性。（３）三倍体卵叶韭Ａｌｉｕｍｏｖａｌｉｆｏｌｉｕｍ高度不育，靠新产生的地下走茎进行无性繁殖，以此扩大居群。（４）根据葱Ａ．ｖｉｃｔｏｒｉａｌｉｓ分布区广而地史相对古老的分布格局，推测它为本组的原始类群。它通过地理的（渐进的）物种形成方式，逐步演化形成现在的各个分类群。（５）根据该组植物的分布格局和演化过程，提出我国横断山区至秦岭一带为本组植物的现代分布中心和分化中心。
Allium Sect. Anguinum G. Don (Liliaceae) includes five species and three varieties. The results of investigation on 23 local populations, representing five species and one variety of this section, are as follows: (1) In this section, the basic chromosome number is x=8, and the karyotypes of all the species belong to 2A type. All the populations have similar metaphase chromosomes. The similar karyotypical features support the viewpoint that Sect. Anguinum is a natural taxon. (2) Despite the fact that the karyotypical features appear to be similar, karyotypical differences exist in some populations within the same species or among the species. First, there are various levels of ploidy. Second, the occurrence, number and shape of B chromosomes are variable among the populations. Third, as for the satellite chromosomes, there is a polymorphism in occurrence of the tandem satellites. (3) Highly sterile triploid of Allium ovalifolium has a kind of stolon and expands population by vegetative propagation. (4) According to widely geographical distribution and relatively old geological history of the geographical area, A. victorialis is considered as a primitive species in this section. This species, by means of geographical (gradual) speciation, has evolved step by step to the other species. (5) According to the geographical distribution and evolutionary process of Sect. Anguinum, it is proposed that the region from the Hengduan Mountains to the Qingling Range of China be the center of present distribution and differentiation of the section.
出处
《植物分类学报》
SCIE
CSCD
1999年第1期20-34,共15页
Acta Phytotaxonomica Sinica
基金
国家自然科学基金
中国科学院植物研究所系统与进化植物学开放研究实验室资助
关键词
葱属
宽叶组
核型
多倍体
种内分化
Allium
Sect. Anguinum
Karyotype
Polyploid
B chromosome
Intraspecific differentiation
Interspecific relationship
