Meiosis Observation of Rumex japonicus Houtt.(Polygonaceae)

In this paper,the meiotic process of pollen mother cells of Rumex japonicus Houtt is reported for the first time.During anaphase I and anaphase Ⅱ,chromosomal bridge,chromosomal fragments and lagging chromosomes have been observed and the abnormality rates of both phases are less than 5%.The rate of fertile pollen grains is more than 95%,which is consistent with the cell abnormality rate at anaphase Ⅱ.These results indicate that meiotic process of R.japonicus is normal,and the somatic chromosome number 2n=2x=100 is credible.