鹅观草属三个物种及其居群间核型变异研究

报道了鹅观草属3个物种,毛叶鹅观草、竖立鹅观草和纤毛鹅观草及其居群间的核型,其中R. amurensis的核型2n=4x=28=24m(2SAT) 4sm为首次报道.结果表明,3个物种绝大多数由中部和近中部着丝点染色体组成,具1对随体,几乎都位于第14对染色体上.核型类型为2A.但在核型公式、平均臂比、臂比大于1.7的染色体比率等方面,不仅3个物种的种间存在一定的差异,而且R. ciliaris和R. japonensis的种内不同居群间也存在差异,表明R. ciliaris和R. japonensis种内具有较大的遗传多样性.

Study on karyotypic variations of three Roegneria species and their accessions

In the present paper, the karyotypes of three Roegneria species: R. amurensis, R. ciliaris, R. japonensis, and karyotypic variations of R. ciliaris and R. japonensis accessions were reported. The karyotype formulae of R. amurensis is 2n=4x=28=24m(2SAT)+4sm, which is reported for the first time. The chromosomes of the three Roegneria taxa are mainly metacentric chromosomes. There are one pairs of satellite chromosomes which are on the chromosome 14. The karyotypes belong to 2A. But the ratio of the longest chromosome to the shortest, the arm ratio in mean and the proportion of chromosome with arm ratio>1.7, were different among the three Roegneria species and the different accessions of R. ciliaris and R. japonensis. The results indicate that there is great genetic diversity among the populations of R. ciliaris and R. japonensis.