荠菜的花粉母细胞减数分裂及核型分析

Karyotype analysis and meiotic observations of pollen mother cells in(Capsella bursa-pastoris L.)Medick

对武汉地区野生荠菜的花粉母细胞减数分裂观察表明，绝大多数花粉母细胞中染色体正常配对与分离，终变期形成16个二价体，其减数分裂为同时型；花粉粒育性为95．06％；荠菜的染色体数目为2n=32，核型公式为K（2n）=4x=32=30m＋2sm，其染色体相对长度组成为2n=4L＋14M2＋10M1＋4S，属于“1B”类型；其染色体实际长度在0．69～1．56um之间，属于小染色体。

The meiosis of pollen mother cells and karyotype were analyzed for the wild plant（ Capsella bursa - pastoris L. ） Medick collected in Wuhan by applying squash method. The result showed that chromosomes of most pollen mother cells were paired as 16 bivalents at diakinesis and segregated as 16：16 at anaphase I . The meiotic division belongs to the simultaneous type, and the stainability of the pollen grains was 95.06%. The chromosome number was 2n =32 and karyotype formula was K（2n） =4x =32 =30m ＋2sm, with relative length from 2n =4L ＋ 14M2 ＋ 10M1 ＋4S,belonging to 1B type. The absolute length of the chromosomes was between 0. 69um and 1.56 um, classified as small chromosome.