摘要： 为研究四倍体萱草育性降低的原因,以四倍体萱草为材料,采用常规涂片法研究花粉母细胞减数分裂行为,并采用离体萌发试验测定花粉活力。结果表明:四倍体萱草花粉母细胞减数分裂过程存在较多的异常。主要表现在:前期出现少量多核现象,染色体的构型复杂,有单价体、二价体、三价体和四价体;中期I和中期Ⅱ有赤道板外染色体;后期和后期Ⅱ出现落后染色体、丢失染色体和染色体桥;中期I开始出现染色体分离不同步现象;四分体时期出现三分体、异常四分体及多分体。各时期减数分裂正常的花粉母细胞平均频率为60.18%,异常频率为39.82%,花粉离体培养萌发率为55.42%,两者存在相关性,减数分裂异常是影响四倍体萱草花粉活力的最重要因素。

关键词: 四倍体, 萱草, 减数分裂, 花粉育性

Abstract: In order to investigate fertility reduction of tetraploid Hemerocallis,the meiosis and chromosome behavior of pollen mother cells(PMCs) in tetraploid Hemerocallis were studied using chromosome preparation technique.And the pollen viability was determined by vitro germination experiment.The results showed that PMCs meiosis of tetraploid Hemerocallis was abnormal:In prophase I,bi-nucleoluses were observed.In diakinesis,quadrivalent,trivalent and univalent were observed.Some of the chromosomes were found not to rank at equatorial plate in metaphase I and metaphaseⅡcells.In anaphase I and anaphaseⅡcells,there were lagged chromosomes,lost chromosome and chromosome bridge.At tetrad stage,triad,tetrad with micronucleus and polyed appeared.In meiosis,the normal PMCs were 60.18% and abnormal PMCs were 39.82%.The abnormal meiosis was the most important reason of pollen fertility reduction of tetraploid Hemerocallis.

Key words: Tetraploid Hemerocallis, Meiosis, Pollen viability

中图分类号: 

• S685.03