ASSESSMENT OF GENETIC VARIABILITY AMONG RASPBERRY ACCESSIONS USING MOLECULAR MARKERS

In this study, random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) loci were used to investigate the genetic relationships in a group of 22 raspberry accessions. Fifteen RAPD primers generated a total of 324 bands, among them 94.1% were polymorphic. From ten used SSR pairs of primers, nine generated only polymorphic bands and the average percentage of polymorphism was 97.8%. Genetic similarity indices calculated on the basis of RAPD and SSR data indicated a wide range of genetic variability of the analyzed raspberry collection. Cluster analysis by UPGMA (Unweighted Pair-Group Method with Arithmetic averaging) and PCA (Principal Component Analysis) clearly delineated the genetic relationships among all the accessions. The highest genetic similarity, determined on the basis of RAPD and SSR markers, was found between two Polish cultivars - 'Polesie' and 'Polesie Zolte', whilst 'Jewel' from USA, belonging to Rubus occidentalis, was found to be the cultivar that varied most from all the accessions. The obtained results confirmed the usability of RAPD and SSR markers for discriminating among closely related raspberries and for determining the genetic variability among cultivars. It might be helpful for breeders to plan their breeding strategy.