Molecular fingerprinting and assessment of genetic diversity in rose (Rosa x hybrida)

Rose (Rosa x hybrida) is economically important floricultural crop and represents a major product for commercial floriculture market as well as oil industry. Understanding its genetic diversity is important for crop improvement programmes, while DNA fingerprinting for accurate identification of clones, cultivars and varieties. In the present investigation, genetic variability among 32 rose cultivars were analysed by using 20 RAPD and 10 ISSR markers, where a total of 306 bands were detected with a range of 6 to 18 bands per marker. ISSR markers were found to be more useful since the average polymorphic information content (PIC), resolving power of primer (RP) and marker index (MI) was better compared to that of RAPD markers. UPGMA-cluster-analysis based on genetic distance coefficients ranged 0.44 to 0.91, clearly distinguished all the genotypes, including Suryodaya and Suryakiran, which are morphologically almost identical. Thus the molecular fingerprinting data of rose cultivars generated in the present study would be helpful for the varietal identification and conservation. Moreover, results of diversity analysis suggested that the cultivated rose varieties display a high level of genetic variability despite the fact that the morphological and physiological characters were found to be less polymorphic.