昭觉林蛙的染色体组型分析

ANALYSIS FOR THE KARYOTYPE OF RANA JAPONICA CHAOCHIAOENSIS

本研究用长骨骨髓细胞，采用秋水仙碱──低渗──空气干燥直接制片法制作染色体玻片标本。昭觉林蛙（Ｒａｎａ ｊａｐｏｎｉｃａｃｈａｏｃｈｉａｏｃｎｓｉｓ）的染色体组型为２ｎ＝２６，由二组染色体组成，即５对大型染色体和３对小型染色体。其中，第２、３、８和９对为亚中部着丝点染色体，其佘各对均为中部着丝点染色体。同时，我们还比较了各染色体对之间的相对长度，推测可能有臂间倒位和相互易位等染色体重组的演化机制存在。

In this paper,the karyotype of Rana japonica chaochiaoensishas beendctermmed from bone marrow cells of the femur bone by the colchicine-hypotonic-airdrying technique The diploid number of chromosomes is 26 (that is 2n=26).They may beclassified into two groups:5 pairs belonging to the larger type, and 8 pairs to the smallertype This classification of the chromosomes is similar to that of other member of thisgcnus Among those pairs,only 2,3, 8 and 9 are submetacentric,while all the rest metacentric chromosomes.We have compared the relative length of cach pair of chromosomes of Rana japonica chaochiaoensis.According to those results we infer that the mechanism of karyotype evolu-tion in Rana genus is probably due to pericentric inversion and reciprocal translocation.