Study of Correlations betweenHorticultural Traits and Variables Affecting Kernel Percentage of Walnut (Juglans regia L.)

Document Type : Research Article


1 Department of Horticulture, Ferdowsi University of Mashhad, Mashhad, Iran

2 Department of Horticulture, Agricultural and Natural Resources Research Center, Shahroud, Iran


Studies of physiological diversity and its effect on the expression of traits in plants are used in breeding programs as a selective tool with the aim of selecting special attributes for creating a new product. In this study, the correlation coefficients among 17 horticultural traits of 34 genotypes from 11 different places of Semnan province were examined. A significant positive correlation was observed between fruit weight and kernel weight, susceptibility to blight and leaf abscission, leafing date and female flower emergence and between kernel percentage, kernel weight and kernel plumpness. Furthermore, a significant negative correlation existed between harvest time and tree vigor, fruit shape and fruit weight and kernel percentage with shell thickness. The most important characteristics that had a direct impact on kernel percentage were shell thickness and kernel plumpness. The attributes that were effective on fruit ripening were tree form, catkin emergence time and shell thickness. However, the residual effects suggested that there might be other important determinant traits for harvest date, which were not considered in this study.


Akca Y, Sen SM (1997) The relationship between dichogamy and yield-nut characteristics in Juglans regia L. Acta Horticulturae. 442, 215–216.
Amiri R, Vahdati K, Mohsenipoor S, Mozaffari MR, Leslie C (2010) Correlations between some horticultural traits in walnut. Horticultural Science. 45, 1690–1694.
Arzani K, MansouriArdakan H, Vezvaei A, Roozban MR (2008) Morphological variation among Persian walnut (Juglans regia L.) genotypes from central Iran. New Zealand Journal of Crop and Horticultural Science. 36, 159-168.
Asadian GH, Pieber K (2005) Morphological variations in walnut varieties of the Mediterranean regions. International Journal of agriculture and biology. 7, 1560-8530.
Aslantas R (2006) Identification of superior walnut (Juglans regia) genotypes in north-eastern Anatolia,
Turkey. New Zealand Journal of Crop and Horticultural Science. 34, 231-237.
Atefi J (1990) Preliminary research of Persian walnut and correlation between pair characters. Acta Horticulture. 284, 97–104.
Bayazit S (2012) Determination of relationships among kernel percentage and yield characteristics in some turkish walnut genotypes by correlation and path analysis. Journal of Animal & Plant Sciences. 22(2), 513-517.
Coates WW (2012) Varietal susceptibility of English walnuts to walnut anthracnose disease (Ophiognomonia leptos pyla). Walnut Research Reports Database. California Walnut Board. 389-191.
Cosmulescu S, Botu M (2012) Walnut biodiversity in south-western Romania resource for perspective cultivars. Pakistan Journal of Botanic .44 (1), 307-311.
Ehteshamnia A, Sharifani M, Vahdati K, Erfani Moghaddam V (2009) Investigation of genetic diversity among some native populations of walnut (Juglans regia L.) in Golestan province by SSR markers. Iran Journal of Plant Production. 16, 39-58. [In Persian].
Eskandari S, Hassani D, Abdi A (2006) Investigation on genetic diversity of Persian walnut and evaluation of promising genotypes. Acta Horticulturae. 705, 159–166.
FAO Statistic Website (2015) Top production Walnuts with shell-2012 http://faostat.fao.Org/site/339/default.aspx.
Ghasemi M, Arzani K, Hassani D (2012) Evaluation and identification of walnut (Juglans regia L.) Genotypes in Markazi province of Iran.Crop Breeding Journal. 2(2) , 119-124.
Germain E (1997) Genetic improvement of the Persian walnut (Juglans regia L.). Acta Horticulturae. 442, 21-32.
Hansche PE, Beres V, Forde HI (1972) Estimates of quantitative genetic properties of walnut and their implications for cultivar improvement. Journal of American Society for Horticulture Science. 97, 279–285.
Kang MS, Miller JD, Tai PYP (1983) Genetic and phenotypic path analysis and heritability in sugar cane. Crop Science. 23, 643–647.
Karimi HR, Zamani Z, Ebadi A, Fatahi R (2009) Morphological diversity of Pistacia species in Iran.  Genetic Resources and Crop Evolution. 56, 561-571.
Mc Granahan GH, Leslie C (1990) Walnuts (Juglans). Acta Horticulture. 290, 905-951.
Michailides TJ, Coates B, Morgan D, Puckett R, Hasey J, Anderson K, Buchner R, DeBuse C, Bentley W (2012) Managing anthracnose blight and botryosphaeria and phomopsis cankers of walnut. Walnut Research Reports Database. California Walnut Board, 381-388.
Mohammadi  SA, Prasanna BM, Singh NN (2003) Sequential path model for determining interrelationship among grain yield and related characters in maize. Crop Science. 43, 1690–1697.
Norouzi R, Heidari S, Asgari-Sarcheshmeh MA, Shahi-Garahlar A (2013) Estimation of Phenotypical and Morphological Differentiation among Some Selected Persian Walnut (Juglans regia L.) Accessions.International Journal of Agronomy and Plant Production. 4(9), 2438-2445.
Papoliyazdi MH, Jalali A (1995) Walnut.Geographical research Journal. 38, 3-36. [In Persian]
Sharma OC, Sharma SD (2001) Genetic divergence in seedling trees of Persian walnut (Juglans regia L.) for various metric nut and kernel characters in Himachal Pradesh. Scientia Horticulturae. 88, 63–171.
Sharma AK, Das B (2003) Genetic variation study on nut and kernel characters of walnut seedlings. Progressive Horticulture. 35, 11-13.
Solar A, Hudina M, Stampar F (2001) Relationship between tree architecture, phonological data and generative development in walnut (Juglans regia L.). Acta Horticulturae. 544, 275–285.
Zeneli G, Kola H, Dida M (2005) Phenotypic variation in native walnut populations of Northern Albania. ScientiaHorticulturae. 105, 91-100.