Chromosome measurements of wild roses of Iran

The genus Rosa is made up of four subgenera, of which the subgenus Rosa (= Eurosa) contains about 95% of all species, and is subdivided into 10 sections. In Iran, there are 15 rose species. In the present investigation, chromosome characteristics of 14 Iranian rose species were studied: Rosa persica, Rosa hemisphaerica, Rosa foetida, Rosa pimpinellifolia, Rosa beggeriana, Rosa boissieri, Rosa iberica, Rosa orientalis, Rosa elimatica, Rosa canina, Rosa pulverulenta, Rosa villosa, Rosa moschata and Rosa x damascena. Chromosome characteristics were measured using image analyzer MicroMeasure 3.3. Genome size and ploidy level of the roses were determined using a flow cytometer. The results of the flow cytometry analysis revealed that the genome size of diploid species was from 0.83 to 1.21 pg, and their genome size by karyotyping measurements was between 46.36 and 56.63 mu m. In tetraploids, the genome size was between 1.91 and 2.29 pg and between 86.55 and 106.31 mu m by flow cytometry and karyotype analysis, respectively. In the pentaploid species, genome sizes were 2.69 to 3.09 pg and 90.35 to 140.96 mu m calculated by flow cytometry and karyotyping analysis, respectively. In hexaploid rose, flow cytometry and karyotyping analysis showed that the genome sizes were 3.54 pg and 147.84 mu m, respectively. R. moschata (2n=2x=14) had the longest total chromosome length of the monoploid set (28.32 mu m) and average length of one chromosome (4.04 mu m). R. orientalis (2n=5x=35) had the longest average length of the small arm (1.76 mu m) and big arm (2.28 mu m). The maximum average ratio of length of big arm to the length of small arm (1.39) was in R. x damascena (2n=4x=28). The results of this study could be used in future rose breeding and in taxonomic and evolutionary studies of Iranian rose species.