Abstract: In order to investigate the relationships between Roegneria.ciliaris(Trin.)Nevski and R.alashanica Keng,and between R.ciliaris and R.magnicaespes D.F.Cui.R.ciliaris(Trin.)Nevski was crossed with the other two species,through the aid of embryo rescue. Hybrids were obtained from these two combinations.Chromosome pairing behavior of parents an dhybrids was observed at metaphase I of pollen mother cells. Meiotic configuratons were 10.62Ⅰ＋8.17Ⅱ＋0.32Ⅲ＋0.02Ⅳ for R.ciliaris×R.magnicaespes and 18.00Ⅰ＋4.76Ⅱ＋0.16Ⅲ for R.ciliaris ×R.magnicaespes;c-value of the two hybrids were 0.44 and 0.21,respectively.

Key words: Genome analysis, Interspecific hybrid, Roegneria

摘要： 为了探索阿拉善鹅观草Roegneria alashanica Keng、大丛鹅观草Roegneria magnicaespes D.F.Cui与纤毛鹅观草Roegneria ciliaris(Trin.)Nevski间的相互关系，将其进行了远缘杂交，通过幼胚离体培养，两个组合均成功合成了杂种。对亲本及杂种F1花粉母细胞减数分裂中期Ⅰ染色体配对行为及形态学进行了统计分析。结果表明，上述物种的种间杂交较难进行，杂种F1减数分裂染色体平均构型分别为：R.ciliaris×R.alashanica 10.62Ⅰ＋8.17Ⅱ＋0.32Ⅲ＋0.02Ⅳ(c-值=0.44)，R.ciliaris×R.magnicaespes 18.00Ⅰ＋4.76Ⅱ＋0.16Ⅲ(c-值=0.21)；杂种穗部特征多数介于双亲之间。阿拉善鹅观草、大丛鹅观草与纤毛鹅观草间至少有一个基因组具有较高的同源性，即为S基因组，本文对它们在分类中的地位也进行了讨论。

关键词: 鹅观草属, 种间杂种, 基因组分析