Genetic identity and relationships of hazelnut (Corylus avellana L.) landraces as revealed by morphological characteristics and molecular markers

• The hazelnut genotypes were phenotypically diverse and many had characteristics appreciated by the market.
• Nut and kernel variables were characteristics with higher variation.
• Simple correlation analysis showed the existence of significant relationships among some characteristics.
• ISSR and RAPD primers generated 140 and 188 polymorphic fragments, respectively.
• The dendrograms based on both molecular data showed two main clusters.

Hazelnut (Corylus avellana L.) is a commercially important species among nut trees and is a traditional crop in Iran. This study describes phenotypic variation in morphological traits and investigates genetic relationships among genotypes and cultivars of hazelnut using ISSR and RAPD markers. The genotypes were phenotypically diverse, which nut and kernel variables were characteristics with higher variation. Simple correlation coefficient analysis showed the existence of significant positive and negative correlations among some characteristics. Ten ISSR and fifteen RAPD primers, which generated 140 and 188 polymorphic fragments, respectively, were able to distinguish genetic variation among genotypes. The dendrograms based on both molecular data showed two main clusters with high variability between genotypes. The results suggested that the studied genotypes were distant from each other and some of them may be directly useful as new cultivars or alternatively as parents in breeding programs. The preservation of this genetic diversity is important.