摘要
采用根尖压片法确定长春蒲公英染色体数目,经分析长春蒲公英核型和花粉母细胞减数分裂行为,确定其倍性。结果表明,长春蒲公英根尖细胞染色体数目为24条,核型公式为2n=2x+x’=24=(8m+6sm+2M)+(5m+3sm),属于2B型。长春蒲公英花粉母细胞减数分裂属于同时型胞质分裂,四分体排列方式以十字交叉型居多。后期Ⅰ减数分裂异常,出现落后染色体,导致四分体存在二分体、三分体、四分体以及多分体等类型,并存在微核现象。结果表明长春蒲公英为异源三倍体,进行不均等的减数分裂。
In this paper,the number of chromosomes in T.junpeianum was calculated by a root tip squashing method.The karyotyping and chromosome behavior was observed,and the ploidity was analyzed during the meiosis process of pollen mother cells.The results showed that the number of chromosomes in T.antungense was 24,and its karyotype was formulated as 2n =2x ＋ x＇ =24 =（8m ＋ 6sm ＋ 2M） ＋ （Sm ＋ 3sm）,which indicates a Stebbins＇ 2 B type.The meiosis of T.junpeianum was classified to simultaneous cytokinesis,which mainly form in tetrad stage was deoussate.It was found that in metaphase Ⅰ,some lagged chromosomes arise,which did not rank at metaphase plate.The abnormal phenomenon like dyad,triad,tetrad with micronucleus and polyad could be observed at tetrad stage.The observation indicated that T.junpeianum was allotriploid,which meiotic of pollen mother cell （PMC） was uneven.
出处
《西南农业学报》
CSCD
北大核心
2013年第5期2022-2025,共4页
Southwest China Journal of Agricultural Sciences
基金
国家农业部野生植物资源保护项目(农计发[2010]29号)
