Identification of culinary rhubarb (Rheum spp.) cultivars using morphological characterization and RAPD markers

Twelve morphological traits and 47 RAPD (Random Amplified Polymorphic DNA) markers were used to discriminate twelve culinary rhubarb (Rheum spp.) cultivars and to estimate their genetic relatedness. Considerable variability was found among the cultivars analysed. Based on the two types of traits, cluster analyses and multidimensional scaling analyses were performed, resulting in a partly overlapping pattern of relatedness among cultivars. A Mantel correspondence test showed a moderate correlation (r = 0.41) between morphology and molecular markers. Since the development of culinary rhubarb cultivars is not well documented, there is no proper pedigree information for most of the cultivars. However, when comparing our results on morphology and RAPDs with pedigree information for four cultivars, a combination of the two types of data sets appeared to give fairly good information about relatedness among cultivars.