Genetic relationship between cultivated and wild hazelnuts (Corylus avellana L.) collected in northern Spain

摘要

P>The genetic relationships between 40 wild hazelnuts collected in northern Spain and cultivated hazelnuts, including 62 local selections and 14 reference cultivars, were investigated using 13 microsatellite loci. Microsatellite analysis revealed considerable diversity; 91 different alleles were identified with a mean of 7 per locus, and polymorphic information content values ranged from 0.43 to 0.83 with a mean of 0.69. The plot obtained from principal coordinate analysis, the unrooted neighbour-joining tree constructed, and the population structure analysis revealed a high level of differentiation between the locally cultivated forms and the remaining materials. Introgressions within these groups were detected in the three analyses. The results indicate that hazelnuts in northern Spain contain (i) a group of accessions clearly differentiated within the Spanish-Italian gene pool, (ii) a group with intermediate forms probably derived from hybridization and (iii) accessions probably derived through exchange with other geographical areas, especially north-eastern Spain. The presence of these different groups within the local cultivated hazelnut germplasm has consequences for its preservation and use.