Assessment of genetic diversity of oil-bearing rose (Rosa damascena Mill.) using ISSR markers.

Bulgaria has long-standing traditions of cultivating oil-bearing roses and is one of the leading producers of rose essential oil and rose water worldwide. We studied the genetic diversity of twenty-two R. damascena accessions from Bulgaria and Saudi Arabia using 10 inter-simple sequence repeat (ISSR) primers. In total, 212 bands were generated, of which 204 were polymorphic and eight monomorphic. High mean values of polymorphic information content (0.75), effective multiplex ratio (8.90), resolving power (32.40), marker index (6.59), and percentage of polymorphic bands (96.26) were obtained, implying significant genetic variability between the studied genotypes. The ISSR-based analyses showed that the level of polymorphism in this crop is appreciably high (Ne = 1.28, I = 0.24, He = 0.16). The coefficient of genetic differentiation among pre-defined groups was 0.46, indicating that 46% of total genetic variability was between groups and 54% was within groups. The method was appropriate for distinguishing individuals with a high level of similarity. The genetic relationships analysed with PCoA and hierarchical clustering analyses clearly separated the group of Bulgarian R. damascena accessions collected from local industrial plantations from the other two pre-defined groups. The clustering of Bulgarian rose cultivars and accessions from Saudi Arabia was independent of their geographical origin. The reported data could further facilitate the management of genetic resources and the development of rose breeding programs. Our study provides the first data on the genetic diversity of R. damascena accessions from Bulgaria using ISSR markers. [ABSTRACT FROM AUTHOR]