Ploidy level and PCR analyses of transgenic pelargonium plants. Histograms of number of nuclei per channel as a function of relative fluorescence intensity resulting from flow cytometry analysis of nuclei stained with DAPI. Nuclei were isolated from leaf samples of diploid WT control (a) and transgenic (b) plants. (c). Identification of the barnase-barstar transgene (544 bp fragment) by PCR in different P. zonale male sterile plants. C + (positive control: pBI101-PsEND1::barnase-barstar) and TI (negative control). (d). Identification of the ipt transgene (460 bp fragment) by PCR in different P. zonale pSAG12::ipt transgenic plants. C + (positive control: pVDH393-pSAG12::ipt) and TI (negative control).