角堇与大花三色堇染色体核型分析

The Analysis of Chromosome Karyotype of Viola cornuta and Viola wittrockiana

以2份角堇与4份大花三色堇自交系为试验材料,采用染色体常规压片方法,观察和分析了它们的细胞染色体数目、相对长度、平均臂比等核型指标,以明确两种植物细胞学特点,为分类以及育种提供理论依据。结果表明:(1)2份角堇自交系染色体数目均为2n=2x=26,染色体基数为x=13,染色体核型公式分别为2n=2x=26=8m+12sm+6st、2n=2x=26=4m+16sm+6st,核型不对称系数为67.20%~70.10%,核型分类均属于3B。(2)4份大花三色堇自交系均为四倍体,其中2份(EYO-1-2-1-4、DSRFY-1-1-2)染色体数目为44,核型公式为2n=4x=44=4m+16sm+6st、2n=4x=44=16m+24sm+4st;2份(G10-1-3-1-4、XXL-YB-1-1-1-1)染色体数目为48,核型公式分别为2n=4x=48=8m+20sm+20st、2n=4x=48=4m+36sm+8st,核型不对称系数为66.74%~71.77%,核型分类属于2B、3B。

Two kinds of Viola cornuta and four kinds of Viola wittrockiana were used as experiment materials to analyze chromosome karyotype including the chromosome number,relative length and average arm ratio by traditional squash method.The studies on chromosome karyotype of pansy will provide a better understanding of their cytology characteristics and classification,which will lay the foundation for the pansy breeding.The results showed that:(1)chromosome number and the basic chromosome number in the V.cornuta were2n=2x=26and x=13,respectively,and the karyotype formula of these two kinds of plants were2n=2x=26=8m+12sm+6st and2n=2n=26=4m+16sm+6st.The index of karyotypic asymmetry was67.20%-70.10%and their karyotype were classed into3B type.(2)All kinds of V.wittrockiana belong to tetraploid,two of which had44chromosomes and their karyotype formula were2n=4x=44=4m+16sm+6st and2n=4x=44=16m+24sm+4st,respectively,and their karyotype were classed into2B type.The other two of V.wittrockiana had48and their karyotype formula were2n=4x=48=8m+20sm+20st and2n=4x=48=4m+36sm+8st,and their karyotype were classed into3B type.The index of karyotypic asymmetry of all V.wittrockiana was66.74%-71.77%.