多裂蒲公英(T.dissectu Ledeb)染色体的核型分析

Chromosome Karyotype of T. dissectum Ledeb

利用根尖压片法对多裂蒲公英进行有丝分裂观察及核型分析,统计观察了50个准确计数染色体的根尖有丝分裂中期细胞。实验结果表明:多裂蒲公英的染色体数为2n=32,其核型公式为2n=32=28m+2sm+2T。利用有丝分裂过程当中的染色体核型,可以明确区分蒲公英属植物在表现型上难以区别的类型,染色体的数目、相对长度、着丝粒位置和随体有无等都可以作为蒲公英属植物的分类指标而被利用。

The mitosis was observed and the karyotype was analyzed by the method of root tip cells. In order to ascertain the chromosome number of T.dissectum Ledeb, 50 root tip cells of mitosis metaphase were observed and the chromosomes of these cells were accurately taken acount of. The results show that the chromosome number of T.dissectum Ledeb is 2n=32 and the karyotype may be expressed as 2n=32=28m+2sm+2T. By the Karyotype of mitosis, the species of Taraxacum that can not be definitely distinguished by phenotypes may be differentiated. And the chromosome number, relative length, centromere location and satellite may also be acted as the index of classification of Taraxacum.