【摘要】 利用骨髓细胞蒸汽固定法制备染色体标本 ,研究了分布于河南新乡的花背蟾蜍 (Buforaddei)的核型、C 带和Ag NORs。结果表明 :河南产花背蟾蜍体细胞染色体数为 2 2条 ,核型公式为 2n =2 2 ( 2 0m +2sm) ,全部为中部或亚中部着丝点染色体 ,NF =4 4。Ag NORs具有多态现象。C 带核型显示 2 2条染色体的着丝点均正染 ,No .1染色体近着丝粒处有不恒定插入型C 带 ,No.4染色体具有恒定近端部插入型C 带 ,随体部位被正染的仅占所观察细胞的 15%。更多还原

【Abstract】 The chromosome samples were prepared from metaphase marrow cells from Bufo rad dei which distributed in Xinxiang, Henan by steam-fixation method. Karyotype, C-banding and silver-staining nucleolus organizer regions (Ag-NORs) were obse rved on chromosomes. The chromosome number of Bufo raddei is 2n=22(20m+2sm), and all of the chromosomes were metacentric or submetacentric (NF=44). In additi on, polymorphism was found in Ag-NORs whereas all the chromosomes were stained in C-banding. There was a variable insert type C-banding near centromere in No .1 chromosome and an invariable insert type C-banding near terminal position in No.4 chromosome.更多还原