【摘要】 本文对枳、金柑及柑桔三属中的枳、金豆、金弹、宜昌橙(白花)、柚(安江香柚)、柠檬、普通甜橙、冰糖橙、普通野桔、红桔10种材料进行了染色体核型及Giemsa显带的研究。结果表明,染色体数目均为2n=18, 绝对长度变化在1.8～5.2μm范围之间,属于小染色体类群,着丝点均为近中部或中部,臂指数在50～60％之间,基本为对称性核型,N·F值均为36,染色体长度比均≤2:1,属于1A类型;Giemsa显带均以着丝点(C)和端带(T)为基本带型,带纹的分布和多少,不同种之间存在差别。研究结果还表明,染色体组绝对平均长度的变异系统,原始型小于进化型;臂比值原始型偏小;两臂长度相当,标准差、变异系数原始型较小,进化型则相反;臂指数原始型偏低,进化型偏高。更多还原

【Abstract】 In the present paper, the karyotype and C-banding patterns of some, species of citrus were studied,including Poncirus trifoliata Ref., Fortune-lla hindsii ( Champ. ) Swingle, F. japonica ( Thunb. ) Swingle, Citrus han-gensis Swing, C. limon ( L ) Burm. , C. grandis(L. ) Osbeck , C. sinensis ( L ) Osbeck, C. sinensis cv. Bing-tang, C. chuana Hort ex Tseng,C. tan-gerina Hortex Tanaka cv, Chang Sha orange. The results showed that the chromosome number of all these species was the same, 2n = 2x=18. The chromosomes of citrus are small in size and the absolute length va-ries from 1.8 to 5.2 μm, and the chromere is located in the median re-gion or submedian region, the index of arms ranges from 50 to 60%, which belongs to symmetrical karyatype. The fundamental number is 36. The ratio of the length of the largest chromosome to the smallest one is less than or equal to 2 ( lA-type ) . Both the centromeric and telomere bands are basic banding patterns of Citrus chromosomes. The location and amount of the bands are different among species. It also is indicated that comparied with evolutionary form, the primitive form has a less coefficient of variation of absolute mean length of chromosome set, less raito, standard error and coefficient of variation of two arms, and less index of arms. However, evolutionary form has a contrary regularity.更多还原