Physicochemical Properties of Black Walnut (Juglans nigra L.) in the Western Mid-hills of Nepal

Document Type : Research Article


1 Faculty of Agriculture, Agriculture and Forestry University, Rampur, Chitwan, Nepal

2 Multi-Dimensional Action for Development Nepal, Bharatpur-19, Chitwan, Nepal

3 Faculty of Animal Science, Veterinary Science and Fisheries; Department of Animal Nutrition and Fodder Production, Rampur, Chitwan, Nepal


The black walnut (Juglans nigra L.) is an underutilized fruit in the mid-hills of Nepal. However, the physico-chemical properties of Nepalese black walnut are almost unavailable in the literature. Four walnut growing districts namely Baitadi, Dadeldhura, Jumla and East Rukum selected and the black walnut collected at commercial maturity from the local markets. The physical properties were assessed following the IPGRI descriptors, whilst chemical composition by the proximate method across the location. The energy content estimated from the fat, protein and carbohydrate values obtained from the proximate content. The nut weight, kernel weight, nut length, nut diameter were found significantly affected by site, while the effect was similar for the kernel ratio (19-23%). A strong positive correlation (r2 = 0.58) was found between moisture and nut diameter, between moisture and nut weight (r2 = 0.52) and between nut weight and kernel weight (r2 = 0.64). The moisture content, crude protein and total ash content were unaffected by site, whilst the crude fibre, crude fat and soluble carbohydrate content were differed by location of sample collection. The proximate revealed the very best fat or oil content in Dadeldhura district (53.05%), the highest crude fibre in East Rukum district (7.26%), whilst the carbohydrate was found highest in the Jumla (24.69%). The low carbohydrate content in walnut of Dadeldhura might be a hint for the drought tolerance genotype of black walnut. It’s still early to conclude the location effect on black walnut quality without a detailed analysis of environmental and genotypic studies.


Acharya GR, Koirala PN, Neupane L, Devkota SC (2009) Livelihood Option from Minor Forest Produce: Context of Non-Timber Forest Product and Poverty Reduction in Mid Hills of Nepal. Journal of Wetlands Ecology. 2, 57–66.
Acharya KP (2006) Linking trees on farms with biodiversity conservation in subsistence farming systems in Nepal. Biodiversity and Conservation. 15, 631 – 646. https : // doi . org/10.1007/s10531-005-2091-7.
Akca Y, Mehmet Sen S (1995) The relationship between dichogamy and yield-nut characteristics in Juglans regia L. Acta Horticulturae. 442, 215-216.
Anderson KJ, Teuber SS, Gobeille A, Cremin P, Waterhouse AL, Steinberg FM (2018) Walnut polyphenolics inhibit in vitro human plasma and LDL oxidation. The Journal of Nutrition. 131, 2837 – 2842. https : // doi . org /10.1093/jn/131.11.2837.
AOAC (1997) Official methods of analysis. Association of Analytical Chemists. Arlington, VA, USA.
Aryapak S, Ziarati P (2014) Nutritive value of Persian walnut (Juglans regia L.) orchards. American- Eurasian Journal of Agriculture and Environmental Science. 14, 1228-1235.
Bhattarai BP, Tomar CC (2009) Effect of Integrated Nutrient Management on Leaf Nutrient Status of Walnut (Juglans regia L .). Nepal Journal of Science and Technology. 10, 63–67.
CBS (2019) Distiect profiels of Nepal. Central bureau of statistics, Kathmandu, Nepal. Retrived from
Chatrabnous N, Yazdani N, Vahdati, K (2018) Determination of nutritional value and oxidative stability of fresh walnut. Journal of Nut. 9(1), 11-20. DOI : 10 . 22034 /jon . 2018 .540862.
Dogan BM, Akgul A, Faculty E,  Faculty A (2005) Fatty acid composition of some walnut (Juglans regia L.) cultivars from east Anatolia. Grasas y Aceites. 56, 328–331.
Ebrahimi A, Khadivi-Khub A, Nosrati Z, Karimi R (2015) Identification of superior walnut (Juglans regia) genotypes with late leafing and high kernel quality in Iran. Scientia Horticulturae. 193, 195-201.
Ehteshamnia A, Sharifani M,  Vahdati K (2010) Investigation of qualitative morphological and geographical diversity among native populations of walnut (Juglans regia L.) in Golestan province. Journal of Plant Production. 17(2), 15-38.
Ehteshamnia A, Sharifani M, Vahdati K, Erfani MV, Mousavizadeh S, Mohseni PTS (2009) Investigation of morphological diversity among native populations of walnut (Juglans regia) in Golestan Province, of Iran. Journal of Plant Production. 16(3), 29-48.
Elmeer Kh, Mattat I, Al-Malki A, Al-Mamari AG, BoJulaia K, Hamwieh A,  and Baum M (2019) Assessing genetic diversity of shishi date palm cultivars in saudi arabia and‎ qatar using‎ microsatellite markers‎. International Journal of Horticultural Science and Technology. 6(1), 1-9.
Etehadpour M, Tavassolian I ( 2019) Ecological factors regulate essential oil yield, percent and compositions of endemic yarrow (Achillea eriophora DC.) in Southeast Iran. International Journal of Horticultural Science and Technology. 6(2), 201-215.
Farsi M, Fatahi Moghadam MR, Zamani Z, Hassani D (2018) Effects of scion cultivar, rootstock age and hormonal treatment on minigrafting of Persian walnut. International Journal of Horticultural Science and Technology. 5(2), 185-197.
Gandev S (2007) Budding and grafting of the walnut (Juglans regia L.) and their effectiveness in Bulgaria. Bulgarian Journal of Agricultural Science. 13, 683-689.
Gauthier MM, Jacobs DF (2011) Walnut (Juglans spp.) ecophysiology in response to environmental stresses and potential acclimation to climate change. Annals of Forest Science. 68, 1277-1290.
Ghanbari AMF,  ShokouhianA, Pyrayesh A (2018) Evaluation of quantitative and qualitative characteristics of persian walnut (Juglans regia L.) genotypes in the west of Meshkin-Shahr. Journal of Nuts. 9(1), 57-65. DOI: 10.22034/jon.2018.540866.
Ghasemi K, Ghasemi Y, Ehteshamnia A, Nabavi SM, Nabavi SF, Ebrahimzadeh MA, Pourmorad F (2011) Influence of environmental factors on antioxidant activity, phenol and flavonoids contents of walnut (Juglans regia L.) green husks. Journal of Medicinal Plants Research. 5(7), 1128-1133.
Golzari M, Rahemi M, Hassani D, Vahdati K,  Dalalpour MN (2013) Protein content, fat and fatty acids of kernel in some Persian walnut (Juglans regia L.) cultivars affected by kind of pollen. Iranian Journal of Food Science and Technology. 10(38), 21-31.
Hassankhah A, Vahdati K, Rahemi M, Hassani D, Sarikhani Khorami S (2017) Persian walnut phenology: effect of chilling and heat requirements on budbreak and flowering date. International Journal of Horticultural Science and Technology. 4(2), 259-271
Heidari L, Boroomand N, Sadat-Hosseini M (2019) The effect of different water potentials on seed germination and growth of some Persian walnut populations. Journal of Nuts. 10(2): 186-201. DOI: 10. 22034/ jon. 2019 .1869808. 1058.
Igara CE, Omoboyowa DA, Uchegbu RI, Ahuchaogu AA (2017) Phytochemical composition, proximate analysis and vitamin content of (Tetracarpidium conophorum ) wall nut seed. Chemical Research Journal. 2,1–8.
IPGRI (1994) Descriptiors for walnut (Juglans spp.). International Plant Genetic Resources Institute (IPGRI), Rome, Italy. pp 1-51 (ISBN:13:978-92-9043-211-1). 
Jahanbani R, Ghaffari SM, Salami M, Vahdati K, Sepehri H,  Namazi Sarvestani N, Sheibani N, Moosavi-Movahedi AA (2016) Antioxidant and anticancer activities of walnut (Juglans regia L.) protein hydrolysates using different proteases. Plant Foods and Human Nutrition. 71, 402-409.
Kamal A, Åke B, Britta O (2009) Uncultivated plants and livelihood support –a case study from the Chepang people of Nepal. Ethnobotany Research and Applications. 7, 409-422.
Kelc D, Stampar F, Solar A, Diversity G (2007) Fruiting behaviour of walnut trees influences the relationship between the morphometric traits of the parent wood and nut weight. Journal of Horticultural Science and Biotechnology. 82, 439-445. https: // doi .org/10.1080/14620316.2007.11512256.
Khadivi-Khub A, Ebrahimi A, Sheibani F, Esmaeili A (2015) Phenological and pomological characterization of Persian walnut to select promising trees. Euphytica. 205, 557–567.
Karimi R, Ershadi A, Ehteshamnia A, Sharifani M, Rasouli M, Ebrahimi A,  Vahdati K (2014) Morphological and molecular evaluation of Persian walnut populations in northern and western regions of Iran. Journal of Nuts. 5(2), 21-31.
Karimi R, Ershadi A, Vahdati K,  Woeste K (2010) Molecular characterization of Persian walnut populations in Iran with microsatellite markers. HortScience. 45(9), 1403-1406. DOI:
Mirzabea AH, Ráufib A, Mansouria A,  Vahdatib K (2014) Advanced Crop Science. Science. 4(1), 24-40.
Gharibzahedi SMT, Mousavi M, Hamedi M, Khodaiyan F (2011) Determination and characterization of kernel biochemical composition and functional compounds of Persian walnut oil. Journal of Food Science and Technology. 51, 34-42.
Mohebi A (2019) Effects of superabsorbents on growth and physiological responses of date palm seedling under water deficit conditions. International Journal of Horticultural Science and Technology. 6(1), 77-88.
Özkan BG, Koyuncu MA (2005) Physical and chemical composition of some walnut (Juglans regia L.) genotypes grown in Turkey. Grasas y Aceites. 56,141–146.
Parvin P, Khezri M, Tavasolian I, Hosseini H (2015) The effect of Gibbrellic acid and chilling stratification on seed germination of Eastern black walnut (Juglans nigra L.). International Journal of Nutrition Related Sciences. 6, 67–76.
Ramos DE, Brown LC, Uriu K, Marangoni B (1978) Water stress affects size and quality of walnuts. California Agriculture. 32, 5–8.
Rana N, Kumar P, Rana VS,  Sharma NC (2015) Variation in physico-chemical characteristics of different walnut cultivars grown in himachal pradesh (India). International Journal of Food and Fermentation Technology. 5, 33-37.
Rezaee R, Vahdati K, Valizadeh M (2009) Variability of seedling vigour in Persian walnut as influenced by the vigour and bearing habit of the mother tree. The Journal of Horticultural Science and Biotechnology. 84, 228-232.
Rodriguez R, Revilla A, Albuerne M, Perez C (1989) Walnut (Juglans spp.) Trees II (pp. 99-126): Springer.
Roozban MR, Mohamadi N, Vahdati K (2005) Fat content and fatty acid composition of four Iranian pistachio varieties grown in Iran. Acta Horticulturae. 726, 573-577.
Shojaeiyan A, Rashidi Monfared S, Ayyari M (2018) Quantitative assessment of diosgenin from different ecotypes of iranian fenugreek
(Trigonella foenum-graecum L.) by
high-performance liquid chromatography. International Journal of Horticultural Science and Technology. 5(1), 103-109.
Taha NA, Al-wadaan, MA (2011) Utility and importance of walnut, Juglans regia Linn: A review. African Journal of Microbiology Research. 5, 5796–5805. https : // doi. org /10.5897/AJMR11.610.
Vahdati K, Sarikhani Khorami S, Arab MM (2018) Walnut: a potential multipurpose nut crop for reclaiming deteriorated lands and environment. Acta Horticulturae. 1190, 95-100. DOI: 10.17660/ActaHortic. 2018.1190.16.
Woeste K, Burns R, Rhodes O, Michler C (2002) Microsatellite Loci From Black Walnut. Journal of Heredity. 93, 58–60.