Morphophysiological and Phytochemical Diversity of Hazelnut (Corylus avellana L.) Populations in Northwestern Iran

Due to the nutritional and pharmaceutical importance of hazelnut (Corylus avellana L.), the morphophysiological and phytochemical diversity of 15 Iranian hazelnut populations with two commercial cultivars were studied. The genotypes had significant differences in morphophysiological and phytochemical characteristics. The significant variance among genotypes (p<0.01) and high genetic variance (σ2g) indicated the divearsity in most traits. The highest coefficient of genetic changes was related to the percentage of fruit kernel, kernel width, calcium, phosphorus, total phenol and taxol. The main components did not correspond to different traits.  Mantel test showed that the correlation between the groupings based on morphological traits and climatic variability was 0.67%, while it was 0.51% for the phytochemical traits and 0.41% for taxol. The significant diversity among hazelnut genotypes and also the mismatch with climatic diversity indicated the role of genetic factors on traits, which can be used in future breeding programs to produce superior hazelnut cultivars.