3种花色野鸢尾形态性状变异及染色体核型分析

对3种花色野鸢尾进行形态性状变异及染色体核型分析,结果表明:蓝紫色花野鸢尾的变异系数为10.47%~65.16%,黄色花野鸢尾的变异系数为4.46%~45.95%,白色花野鸢尾的变异系数为3.95%~55.43%。蓝紫色、黄色和白色3种花色野鸢尾的颜色差异明显;开花时间分别为15:00、14:00、16:00,闭合时间分别为19:30、19:00、20:00;3种花色野鸢尾的分蘖数和种子数差异不显著,花冠幅、外花被长、内花被宽、果实长等13个性状存在显著差异。蓝紫色花野鸢尾的核型公式为2n=2x=32=12sm+20m,核型类型为1B;黄色花野鸢尾的核型公式为2n=2x=32=6sm+26m,核型类型为1A;白色花野鸢尾的核型公式为2n=2x=32=8sm+24m,核型类型为2B;黄色花野鸢尾的核型为国内、外首次报道。探讨了3种花色野鸢尾的亲缘关系,初步推测黄色花和白色花为蓝紫色花的种内变异。

The studies of morphological variations and karyotype on three Iris dichotoma with different flower colors

Three groups of Iris dichotoma with different flower colors were investigated by morphological comparison and Karyotype analysis. The results indicated that there were obvious differences among the three groups with violet, yellow and white flowers, respectively. Their flowering time were 15:00, 14:00 and 16:00, and closing time were was 19:30, 19:00 and 20:00, respectively. The respective average variation coefficients of I. dichotoma with different flower colors were 10.47%~65.16%, 4.46%~45.95% and 3.95%~55.43%. The variation of 13 characters of three groups such as flower diameter, outer perianth, inner perianth and fruit length had significant difference, while there was no significant difference in the tillering number and the number of seeds. The analysis of karyotype demonstrated that the karyotype formula for I. dichotoma (Violet) was 2n=2x=32=12sm 20m, and the karyotype was 1B. The chromosome number and karyotype of I. dichotoma(Yellow) were reported here for the first time and its karyotype formula was 2n=2x=32=6sm 26m, belonging to "1A" type. The karyotype of I. dichotoma(White) was 2B, whose karyotype formula was 2n=2x=32=8sm 24m. By the analysis of karyotype and variation of morphological characters, the genetic relationships among the three different flower color groups of I. dichotoma were discussed, which showed that their phylogenetic relationships were relatively close and I. dichotoma(Yellow) as well as I. dichotoma(White) should be the intraspecific variation of I. dichotoma (Violet).