芸薹类蔬菜（n＝10）染色体G─带的研究

Studies on Chromosome G-banding in 10-Chromosome Vegetables of Brassica

采用改良的ＡＳＧ法首次在ｎ＝１０的芸薹类蔬菜（即不结球白菜、结球白菜、日本水菜和芜菁等）各品种的有丝分裂染色体上显示了Ｇ－带，并对其进行了Ｇ－带带型分析。所试材料的Ｇ－带，除随体染色体管外，都沿整个染色体的长轴分布，是一些密切邻近的多重带纹。在有丝分裂的晚前期、早中期和中期的染色体都有这样的带纹，同一品种的带纹数目从有丝分裂晚前期到中期逐渐减少。每一对同源染色体的Ｇ－带带型基本相似，非同源染色体间具有不同程度的差异。亚种或品种间染色体Ｇ－带的总带纹数目在一定范围内有差异。本文讨论了染色体Ｇ－带带型分析在探讨靶薹类蔬菜演化和分类上的作用。

Mitotic chromosome G-banding in cultivars of subspecies of Brassica campestris L. (Chinese cabbabge-non-heading, Chinese cabbage-heading and turnip)and B.japonica sieb (Japanese water-cabbage) have been produced by an advanced ASG method, and their G-patterns of early metaphase chromosome have been studied. Their G-bandings of the plant materials used in these studies are multiple and closely adjacent,distributed all along the length of chromosomes except their arms of satellite chromosomes.The G-bands at late prophase, prometaphase and metaphase chromosomes have been induced, and the number of G-bands of a cultivar decreases gradually from late prophase to metaphase. Each of the two members of the chromosome pairs resembles each other and nonhomologous chromosomes are not the same in G-banding patterns. The number of chromosome G-banding among subspecies or cultivars varies in a lesser degree. ms paper dealed with some role of chromosome G-banding pattern analysis on evolution and taxonomy of 10-chromosome vegetables of Brassica.