Endoreplication and Division before the Pollen Mother Cells of Taraxacum antungense Kitag.(Asteraceae)
To obtain dynamic information on endoreplication as well as a division of the pollen mother cells (PMC) in apomicts T.antungense (2n=3x=24),the entire course of pollen development was observed by the clearing-staining-squash method.Endoreduplication was observed before the PMC.The PMC was formed after endoreduplicational division.The sporogenous cell,which owns 24 chromosomes and chromosomal DNA replication without intervening mitosis.If the chromosomal replicates successively,the ploidy level would increase exponentially.In this process,the volume of cell increases gradually till the ceasing of chromosomal replication.Consequently,alter the division of endoreduplication cell,chromosome number of the PMC becomes normal.There are three kinds of divisions:chromosome division,nuclei division and mix division,meanwhile those processes can produce different sizes of cells.During this period,what we observed are lagging chromosomes and unequal size ceils,which suggest that the pollen sterility is so low.The meaning of the occurrence of endoreduplication process and its regulation mechanism need to be further researched.
Endoreduplication division Taraxacum antungense
Zhang jian Zhao xin Ning wei
College of Horticulture,Shenyang Agricultural University,Shenyang,110886,China
国际会议
The Third Conference on Horticulture Science and Technology (2012第三届园艺科学与技术学术会议(CHST2012))
北京
英文
367-370
2012-11-24（万方平台首次上网日期，不代表论文的发表时间）