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.
Ahmed, N., Mir, J. I., Mir, R. R., Rather, N. A., Rashid, R., Wani, S. H., Shafi, W., Mir, H. and Sheikh, M. A. (2012): SSR and RAPD analysis of genetic diversity in walnut (Juglans regia L.) genotypes from Jammu and Kashmir, India.–Physiol. Mol. Biol. Plants 18(2): 149–160 (2012).
Arab, M. M., Marrano, A., Abdollahi-Arpanahi, R., Leslie, C. A., Askari, H., Neale, D. B. and Vahdati, K. (2019): Genome-wide patterns of population structure and association mapping of nut-related traits in Persian walnut populations from Iran using the Axiom J. regia 700K SNP array.–Sci. Rep. 9(1): 6376.
Aradhya, M., Woeste, K. and Velasco, D. (2010): Genetic diversity, structure and differentiation in cultivated walnut (Juglans regia L).–Acta. Hort. 861: 127–132.
Aradhya, M., Velasco, D., Ibrahimov, Z., Toktoraliev, B., Maghradze, D., Musayev, M., Bobokashvili, Z. and Preece, J. E. (2017): Genetic and ecological insights into glacial refugia of walnut (Juglans regia L.).–PLoS ONE 12(10): 0185974.
Bayazit, S., Kazan, K., Gülbitti, S., Cevik, V., Ayanoglu, H. and Ergül, A. (2007): AFLP analysis of genetic diversity in low chill requiring walnut (Juglans regia L.) genotypes from Hatay, Turkey.–Sci: Hortic. 111: 394–398.
Beug, H. J. (1975): Man as a factor in the vegetational history of the Balkan Peninsula. – In: Jordanov, D., Bondev, I., Kozuharov, S., Kuzmanov, B. and Palamarev, E. (eds): Problems of Balkan flora and vegetation. Publishing House of the Bulgarian Academy of Sciences, Sofia, Bulgaria, pp. 72–78.
CBOL Plant Working Group (2009): A DNA barcode for land plants. – Communicated by Daniel H. Janzen, University of Pennsylvania, Philadelphia, PA.
Ehteshamnia, A. A., Sharifani, M., Vahdati, K. and Erfani Moghadam, V. (2009): Investigation of genetic diversity among some native populations of walnut (Juglans regia L.) in Golestan Province by SSR markers.–J. Plant Prod. 4: 39–58.
Fazekas, A. J., Burgess, K. S., Kesanakurti, P. R., Graham, S. W. and Newmaster, S. G. (2008): Multiple multilocus DNA barcodes from the plastid genome discriminate plant species equally well.–PLoS ONE 3: e2802.
Fjellstrom, R. G., Parfitt, D. E. and Mcgranahan, G. H. (1994): Genetic relationship and characterization of Persian walnut (Juglans regia L.) genotypes using restriction fragment length polymorphisms (RFLPs).–J. Amer. Soc. Hortic. Sci. 119: 833–839.
Hammer, Ø., Harper, D. A. T. and Ryan, P. D. (2012): PAST: Paleontological statistics software package for education and data analysis.–Pal. Electronica 4: 9.
Hollingsworth, P. M., Graham, S. W. and Little, D. P. (2011): Choosing and using a plant DNA barcode.–PLoS ONE 6(5): e19254.
Kalendar, R. and Schulman, A. H. (2006): IRAP and REMAP for retrotransposon-based genotyping and fingerprinting.–Nat Protoc. 1(5): 2478–2484.
Karimi, R., Ershadi, A., Vahdati, K., Ehtesham Nia, A., Sharifani, M., Rasouli, M. and Ebrahimi, A. (2014): Morphological and molecular evaluation of Persian walnut populations in northern and western regions of Iran.–J. Nuts 5(2): 21–31.
Križman, M., Jakše, J., Baričevič, D., Javornik, B. and Prošek, M. (2006): Robust CTAB-activated charcoal protocol for plant DNA extraction.–Acta Agric. Sloven. 87: 427–433.
Laiou, A., Aconiti Mandolini, L., Piredda, R., Bellarosa, R. and Simeone, M. C. (2013): DNA barcoding as a complementary tool for conservation and valorisation of forest resources.–ZooKeys 365: 197–213.
Maghsoodi, M., Sheidai, M. and Koohdar, F. (2018): Population genetic study in Juglans regia L. (Persian walnut) and its taxonomic status within the genus Juglans L.–Phytotaxa 376: 154–166.
Mohsenipoor, S., Vahdati, K., Amiri, R. and Mozaffari, M. (2010): Study of the genetic structure and gene flow in Persian walnut (Juglans regia L.) using SSR markers.–Acta Hortic. 861: 133–142.
Nematollahi, A., Vahdati, K., Golein, B., Nabipour, A. and Danesh, M. (2009): Assessment of genetic variation in citrus germplasm of south of Iran using SSR markers.–Acta Hortic. 839: 549–554.
Nicese, F. P., Hormaza, J. I. and Mcgranahan, G. H. (1998): Molecular characterization and genetic relatedness among walnut (Juglans regia L.) genotypes based on RAPD markers.–Euphytica 101: 199–206.
Ninot, A. and Aletà, N. (2003): Identification and genetic relationship of Persian walnut genotypes using isozyme markers.–J. Amer. Pomol. Soc. 57: 106–114.
Peakall, R. and Smouse, P. E. (2006): GENALEX 6: genetic analysis in Excel. Population genetic software for teaching and research.–Mol. Ecol. Notes 6: 288–295.
Podani, J. (2000): Introduction to the exploration of multivariate data. – Backhuys, Leiden, 407 pp.
Pop, I. F., Vicol, A. C., Botu, M., Raica, P. A., Vahdati, K. and Pamfil, D. (2013): Relationships of walnut genotypes in a germplasm collection: Comparative analysis of phenotypic and molecular data.–Sci. Hortic. 153: 124–135.
Popov, K. P. (1994): Trees, shrubs, and semishrubs in the mountains of Turkmenistan. – In: Fet, V. and Atamuradov, K. I. (eds): Biogeography and ecology of Turkmenistan. Springer, Dordrecht, pp. 173–186.
Popov, M. G. (1929): Wild growing fruit trees and shrubs of Asia Minor.–Bull. Appl. Bot. Pl. Breed. 22: 241–483. [in Russian]
Ruiz-Garcia, L., Lopez-Ortega, G., Denia, A. F. and Frutos Tomas, D. F. (2011): Identification of a walnut (Juglans regia L.) germplasm collection and evaluation of their genetic variability by microsatellite markers.–Spanish J. Agric. Res. 9: 179–192.
Sadat-Hosseini, M., Vahdati, K. and Leslie, C. A. (2019): Germination of Persian walnut somatic embryos and evaluation of their genetic stability by ISSR fingerprinting and flow cytometry.–HortScience 54(9): 1576–1580.
Shaw, J. and Small, R. L. (2005): Chloroplast DNA phylogeny and phylogeography of the North American plums (Prunus subgenus Prunus section Prunocerasus, Rosaceae).–Amer. J. Bot. 92: 2011–2030.
Sheidai, M., Taban, F., Talebi, S. M. and Noormohammadi, Z. (2016): Genetic and morphological diversity in Stachys lavandulifolia (Lamiaceae) populations.–Biologija 62(1): 9–24.
Sheidai, M., Zanganeh, S., Haji-Ramezanali, R., Nouroozi, M., Noormohammadi, Z. and Ghasemzadeh-Baraki, S. (2013): Genetic diversity and population structure in four Cirsium (Asteraceae) species.–Biologia 68: 384–397.
Solar, A., Smole, J., Štampar, F. and Viršček-Marn, M. (1994): Characterization of isozyme variation in walnut (Juglans regia L.).–Euphytica 77: 105–112.
Tamura, K., Peterson, D., Peterson, N., Stecher, G., Nei, M. and Kumar, S. (2012): MEGA5: molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods.–Mol. Biol. Evol. 28(10): 2731–2739.
Timmer, J. C., Enoksson, M., Wildfang, E., Zhu, W., Igarashi, Y., Denault, J. B., Ma, Y., Dummitt, B., Chang, Y. H., Mast, A. E., Eroshkin, A., Smith, J. W., Tao, W. A. and Salvesen, G. S. (2007): Profiling constitutive proteolytic events in vivo.–Biochem. J. 407(1): 41–48.
Wang, H., Pei, D., Gu, R.-S. and Wang, B.-Q. (2008): Genetic diversity and structure of walnut populations in Central and Southwestern China revealed by microsatellite markers.–J. Amer. Soc. Hort. Sci. 133(2): 197–203.
Weising, K., Nybom, H., Wolff, K. and Kahl, G. (2005): DNA Fingerprinting in plants. – In: Principles, methods, and applications. (2nd ed.). CRC Press, Boca Rayton, 472 pp.
Zohary, D. and Hopf, M. (1993): Domestication of plants in the old world. – Clarendon Press, Oxford, 249 pp.