Thirty two radish(Raphanus sativus L. ) accessions with different flesh colors were used to analyze the karyotypes and the red pigment content for the first time. It showed that the red accessions with red flesh had a high red pigment content as high as 16. 21% on the average (ranging from 3. 4%o~28. 8%o) , and there existed significant differences in the red pigment content between accessions. With the same number of chromosomes (2n = 2x=18) the karyotype formulae of the red radish with red flesh,green radish with red flesh,white radish with red flesh, and white radish were 14m + 4sm, 16 tn + 2 sm,as well as 18m,and belonged to 2A,Lb,La,and 1 A, respectively. As all the accessions without satellites presented almost exclusively m and sm chromosomes,some changes in chromosome size and structure occurred but no great changes in chromosome morphology were obseved. Ranking of radish accessions based on the chromosomal a-symmetry index was in turn: the red radish with red flesh,green radish with red flesh,red radish with white flesh,and white radish. With respect to the karyotype evolution,the white flesh radish could be considered more ancestral than the red flesh accessions. In additon,it was deduced that the latter might be a variant of the former.%以红皮红心、绿皮红心、红皮白心和白皮白心4种不同肉质颜色的32份萝卜品种为材料,室内检测红色肉质萝卜的色素含量及镜检观测不同颜色肉质萝卜的核型.结果表明,供试红色肉质萝卜色素含量变幅为3.4‰～28.8％,基因型间存在显著差异.不同颜色肉质萝卜品种的染色体数目均为2n=2x=18,且未见随体,红皮红心萝卜核型公式为2n=2x=14m+4 sm,属于2A型,核不对称系数为59.28％；绿皮红心萝卜核型公式为2n=2 x=16m+2 sm,属于1B型；红皮白心萝卜核型公式为2 n=2 x=18 m,属于1A型；白皮白心萝卜核型公式为2 n=2x=16m+2sm,属于1A型.从核型进化看,红色肉质萝卜比白色肉质萝卜进化程度高,红色肉质萝卜可能是由白色肉质萝卜演化而来,据此推测,红色肉质萝卜可能是白色肉质萝卜的变种.
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