Study on the Cytology of Rosa multiflora Thunb.var.cathayensis

The chromosome number and meiosis of Rosa multiflora var.cathayensis were studied.First at all,the triploid of Rosa multiflora var.cathayensis was confirmed(2n=3x=21).Secondly,it was observed that the meiosis of Rosa multiflora var.cathayensis began at the first ten days of April.At this time,the blossom buds began to swell,but not dehiscent.The color of petals changed from green to yellow.The meiotic behaviors of pollen mother cells were non-synchronism,meiosis phase from prophase to telophaseⅡ could be found in the same anther.The abnormal phenomena of meiosis such as univalent,chromosome bridges and lagging chromosomes were observed.Finally,the relation between the fertility and the abnormal pollen mother cells was conducted on the cytogenetics.The fertile pollens are useful for Rosa multiflora var.cathayensis breeding practice.