STUDY OF EFFICIENCY OF CP-DNA GENE, IRAP, AND REMAP MARKERS FOR STUDY OF GENETIC DIVERSITY OF SOME IRANIAN WALNUT POPULATIONS

The Persian walnut, also known Juglans regia of the genus Juglans is cultivated throughout the temperate regions of the world for its high-quality wood and edible nuts. Genetic diversity, structure and differentiation of cultivated walnut are important for effective conservation, management, and utilisation of germplasm. Recent study on genetic diversity and genotype differentiation in Persian walnut of Iran, revealed that these genotypes can be differentiated by ITS and ISSR, however, these markers show a low degree of genetic variability. ITS sequences revealed a lower degree of genetic difference of the studied Persian walnut genotypes compared to that of ISSR molecular markers. Therefore, it is important to investigate these genotypes by the other molecular markers to find out which one can produce more data on genetic structure and variability in these important genotypes. For the same reason, we continued this study by using cp-DNA (psbA-trnhG) gene, IRAP, and REMAP. To provide barcode for Iranian genotypes of Juglans regia is an other objective of this study. For IRAP and REMAP analyses studies, we randomly selected 60 plants from 6 populations including 3 wild and 3 cultivated populations. For cp- DNA analysis we used 21 plants of Juglans regia randomly selected from 6 studied populations. The present study revealed a high level of genetic variability in Juglans regia genotypes in those sequences investigated by IRAP and REMAP molecular markers. We reported that IRAP and REMAP molecular markers cannot be efficiently used in walnut germplasm genetic screening.