勋章菊品种核型分析

选用4个不同株形和花色的勋章菊品种进行染色体核型分析，结果表明：（1）勋章菊品种‘红纹’、‘星白’、‘日出’的体细胞染色体数均为2n = 10，而‘中国勋章菊’为2n = 20，推测勋章菊属植物的染色体基数为x = 5，而‘中国勋章菊’为四倍体。（2）‘红纹’、‘星白’、‘日出’的核型公式分别为2n = 8m + 2sm、2n = 8m + 2sm和2n = 10m；‘中国勋章菊’的核型公式为2n = 18m + 2sm。（3）4个勋章菊品种的核型不对称系数为53.80% ~ 58.84%；除‘日出’的核型类型为“1A”，其余3个品种均为“2A”型，核型较对称。（4）从染色体核型分析结果可知，3个外引品种的亲缘关系较近。

The Karyotype Analysis of Gazania rigens Varieties

Four different types and colors of Gazania varieties were chosen to chromosomes karyotype analysis. The results showed that：(1) The number of somatic chromosomes of G. rigens varieties ‘Hongwen’，‘Xingbai’and‘Richu’were 2n = 10，‘Zhongguo Xunzhangju’was 2n = 20. It is speculated that the cardinal number of chromosomes in G. rigens plants was x = 5，while the‘Zhongguo Xunzhangju’was tetraploid. (2) The karyotype formulae of‘Hongwen’，‘Xingbai’and‘Richu’respectively were 2n = 8m + 2sm，2n = 8m + 2sm and 2n = 10m. The karyotype formula of‘Zhongguo Xunzhangju’was 2n = 18m + 2sm. (3) The asymmetrical karyotype coefficient of four G. rigens varieties were 53.80%–58.84%. Except the karyotype type of‘Richu’was“1A”，the three remaining species were“2A”，and the karyotypes were relatively symmetric. (4) The results of karyotype analysis showed that three introduced species had a near genetic relationship.