Genetic Diversity and Relationship Assessment based on AFLP Analysis in Blackberry (Rubus fructicosus L.) Mutant Lines

This study was carried out to evaluate the genetic diversity and relationships among fifty-six blackberry (Rubus fructicosus) mutants derived from gamma-ray treatment (fifty-two lines) by analysis of Amplified fragment length polymorphism (AFLP) markers. Both cluster analysis and principal coordinate analysis (PCOORDA) were conducted in order to study the genetic diversity, using both morphological traits and AFLP makers. A total of 589 bands were amplified with an average of 58.9 bands per primer. Among them, 560 were identified to be polymorphic, with a rate of 95.08%. A showed a highly significant (P≤0.01) positive correlation with GD and PIC (r2=0.999). MI also showed a significant (P≤0.05) positive correlation with GD and PIC. According to the clustering analysis, all mutant lines could be classified into five categories, but the three gamma-ray treatment lines and the cross-bred line were not clustered into any groups. For the morphological traits, cluster analysis divided the blackberry germplasm into six clusters and two independent groups. In addition, the morphological dendrogram indicated an unclear pattern of division among the groups based on AFLP analysis. The findings of this study indicate that mutant lines have high genetic diversity, and can be effectively utilized as materials for the improvement of breeding.