Application of ISSRs for cultivar identification and assessment of genetic relationships in rose

The inter-simple sequence repeat (ISSR) technique was evaluated for its applicability to cultivar identification and assessment of genetic relationships in rose. Nine ISSR primers that revealed informative patterns were selected to fingerprint (by Resophor agarose gel electrophoresis) 33 cultivars, including unrelated cultivars, sports and offspring obtained by sexual propagation from the same initial variety. A total of 159 fragments were generated using these nine primers, 149 of which (93.7%) were polymorphic. All 33 rose cultivars, except for the known colour sports, were differentiated. A Jaccard's dissimilarity coefficient matrix of the cultivars showed a low dissimilarity level between them (mean dissimilarity: 0.45). An unweighted pair group method with the arithmetic averages dendrogram and principal coordinates analysis separated them into four main groups according to their horticultural classification and pedigree. The ISSR technique is therefore a potentially useful tool for cultivar identification and assessing genetic relationships in rose because it is simple, fast, cost-effective, reliable and highly discriminating.