Abstract：The cultivars obtained by microspore culture in cabbage of two F1 cultivars No.12 and No.22 were studied.Firstly,ploidys of the two F1 cultivars were detected by using flow cytometry.Secondly,the size of stomata protective cells was observed and the chloraplast number of doubled haploid cultivars and haploid cultivars with ploidy were counted and identified.The results show that there is a positive relationship between the chloraplast number of stomata protective cells and ploidy of cabbage.The chloraplast numbers of stomata protective cells in doubled haploid cultivars vary from 12 to 17 and that in haploid cultivars vary from 6 to 10.Thus the ratio of the chloraplast number of stomata protective cells in doubled haploid cultivars to that in haploid cultivars is about 2,and there is big difference between the chloraplast number of stomata protective cells in doubled haploid cultivars and of haploid cultivars.So observing the chloraplast number of stomata protective cells could be an easy and effective mean to identify ploidy of cabbage.
