Identification, collection and study of morphological and cytogenetic characteristics of wild Hazelnut population

In this study wild (forest) grown populations of Iranian hazelnut in Western Caspian Sea (Fandoghloo forest, Ardebil province) and Eastern Caspian Sea (Kopeh Dagh region, North Khorasan province) were collected and evaluated using morphological traits and molecular DNA markers. Based on the comparison of characterized populations and their genetic diversities with those of cultivated varieties of Iranian hazelnut showed that all wild (fores) acessions, examined in this study, belonged to the species known as Corylus avellana. High levels of morphologica diversity was observed in both forest populations of hazelnut in Western and Eastern Caspian Sea. According to these results, originally proposed cytological evaluation was found unnecessary. Therefor, molecular evaluation of DNA using simple sequense repeat (SSR) markers was carried out for verifying the results of morphological eveluation and better understanding the diversity structure in Iranian forest populations of hazelnut. Ten genotypes of each of the two forest populations as well as the cultivated variety populations, were DNA fingerprinted by using 13 primer pairs of SSR markers. A total of 84 alleles with an average of 6.5 alleles at each locus was amplified. Maximum number of alleles was observed for SSR locus CAC-B029b with 9 alleles. The mean polymorphic information content (PIC) value of 0.27 for all genotypes and maximum PIC of 0.39 for locus Cat-B502 were estimated. Based on the cluster analysis and principal component analysis of molecular data, genotypes examined in this study were calssified into eight main groups. All forest genotypes of North Khorasan (Eastern Caspian Sea) were placed in one group and those of Ardebil (Western Caspian Sea) were separatly located in five different groups. Results of this study indicated that: firstly, a higher level of genetic diversity was observed in forest population of Ardebil; secondly, as expected, very little genetic exchange has occurred between the isolated hazelnut population in the east and the one in the west of Caspian Sea; thirdly, due to a much higher genetic diversity of hazelnut in western Caspian, most probably, the geneflow in the wild populations of hazelnut in Iran has taken place eastward.