斑叶蒲公英的核型分析和花粉母细胞的减数分裂观察
DOI:
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

基金项目:

国家农业部野生植物资源保护项目(农计发[2010]29号)


Karyotype Analysis and Pollen Mother Cell Meiosis Observation in Taraxacum antungense Kitag.(Asteraceae)
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    采用根尖压片法确定斑叶蒲公英的染色体数目,通过分析斑叶蒲公英核型及花粉母细胞减数分裂过程,以确定其倍性水平。结果表明:(1)斑叶蒲公英根尖细胞染色体数目为32条,核型公式为2n=3x+x′=32=(18m+6sm)+(3m+4sm+1T),属于2A型。(2)斑叶蒲公英花粉母细胞减数分裂为同时型胞质分裂,四分体的排列方式以正四面体型居多,十字交叉型偏少,偶见左右对称型。(3)前期Ⅰ染色体的构型复杂,中期Ⅰ和中期Ⅱ有赤道板外染色体;后期Ⅰ和后期Ⅱ出现落后染色体、染色体桥及断片;后期Ⅱ和末期Ⅱ还出现染色体分离不同步及不均等分裂的现象;四分体时期出现二分体、三分体、含微核的异常四分体及多分体等异常现象。(4)对其花粉进行离体萌发试验,花粉萌发率只有26.3%,说明斑叶蒲公英是异源四倍体,32条染色体不均等的减数分裂异常,造成花粉活性较低。

    Abstract:

    The number of chromosomes in Taraxacum antungense was calculated by a root tip squashing method.The ploidity was analyzed by karyotyping and chromosome behavior observation during the meiosis process of pollen mother cells.Results showed that:(1)The number of chromosomes in T.antungense was 32.Its karyotype was formulated as 2n=3x+x′=32=(18m+6sm)+(3m+4sm+1T),which indicates a Stebbins’ 2A type.(2)The meiosis in T.antungense undergoes simultaneous cytokinesis.(3)Some of the chromosomes were found not to rank at metaphase plate in metaphase Ⅰ and metaphase Ⅱ cells.In anaphase Ⅰ and anaphase Ⅱ cells,observed some abnormal events including lagged chromosomes,chromosome bridge and fragment.During anaphase Ⅱ and telophase Ⅱ chromosome segregation was not synchronous and equal.At tetrad stage,dyad,triad,tetrad with micronucleus and polyad appeared.(4)The pollen germination rate in vitro was only 26.3%,which indicated that abnormal meiosis of PMCs was the cytogenetic reason of fertility reduction of T.antungense pollen.

    参考文献
    相似文献
    引证文献
引用本文

张 建,陈倩倩,赵 鑫,等.斑叶蒲公英的核型分析和花粉母细胞的减数分裂观察[J].西北植物学报,2012,32(12):2419-2425

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:
  • 最后修改日期:
  • 录用日期:
  • 在线发布日期: 2013-01-06
  • 出版日期:

微信公众号二维码

手机版网站二维码