The use of AFLP markers for cultivar identification in apricot

Amplified fragment length polymorphism (AFLP) molecular markers were employed for the fingerprinting of 118 accessions of apricot, including cultivated varieties and related apricot species. Five primer combinations were tested and 165 polymorphic bands produced which could uniquely differentiate all accessions under investigation. Primer combinations were rated according to the multiplex ratio, the polymorphic index content and the discrimination power parameters and superior combinations were identified. AFLP markers were used in cluster analysis carried out with the UPGMA and the neighbourjoining methods and parsimony analysis. Four groups of similar accessions were identified: (i) those from the Mediterranean basin, (ii) from China, (iii) from continental Europe and (iv) mixed Europe– North America accessions. In the principal component analysis the first three components accounted for 17% of the total variability existing among accessions. Because the most important regions where apricot is cultivated in the world were represented in the analysis, with a large number of varieties, it was possible to discuss the data in the light of current phylogenetic hypotheses on the origin and evolution of the species.