Genetic diversity in hazelnut (Corylus avellana L.) cultivars from Black Sea countries assessed using SSR markers

P>European hazelnut (Corylus avellana L.) is an important crop in Turkey, Georgia and Azerbaijan, where cultivars were selected from the native vegetation. Accessions from Turkey have been assigned to the Black Sea group, and cultivars from Georgia and Azerbaijan have a similar phenotype. Genetic diversity was investigated in 88 accessions from these three countries and compared with cultivars from Spain and Italy using 12 microsatellite loci. A high level of genetic diversity (H-e = 0.71, H-o = 0.70) was observed in the Black Sea accessions. Six Turkish accessions in the US hazelnut collections were found to be synonyms of cultivars in the Turkish collection in Giresun. An unweighted pair-group method using arithmetic average dendrogram and principal component analysis of 109 unique accessions showed a tendency to form subgroups by country of origin, and high diversity within each subgroup. A moderate shift in allelic frequencies (F-ST = 0.114-0.131) was seen between accessions from the Black Sea and the Spanish-Italian accessions. Simple sequence repeat analysis identified the putative parents of two Turkish cultivars.