Evaluation of ‘Esterhazy II’ Persian walnut (Juglans regia L.) genotypes from Hungary, Austria, and Switzerland

Evaluation of ‘Esterhazy II’ Persian walnut (Juglans regia L.) genotypes from Hungary, Austria, and Switzerland | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Short Report Evaluation of ‘Esterhazy II’ Persian walnut (Juglans regia L.) genotypes from Hungary, Austria, and Switzerland Géza Bujdosó, Alina Ratiu, Andreas Spornberger, Daniela Noll, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7068639/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 07 Aug, 2025 Read the published version in Genetic Resources and Crop Evolution → Version 1 posted 13 You are reading this latest preprint version Abstract The historic Persian walnut genotype, known as ‘Esterhazy II’ and derived from Hungary, is well-known in the German-speaking countries; however, there are only a few specimens showing significant variability in traits in its native country. In this current study, the aim was to evaluate our genotype, labelled ‘Esterhazy II’, which is planted in the ex-situ gene bank of the Hungarian University of Agriculture and Life Sciences, and compare it to other true-to-type ones. During the examination, the SSR analysis confirmed that the Hungarian ‘Esterhazy II’ is exactly identical to the true-to-type Austrian and Swiss varieties. The Austrian and the Swiss ‘Esterhazy II’ differed significantly in nut height from the control ‘Chandler’. There was no further significant difference in the nut parameters. All Esterhazy genotypes, except ‘Esterhazy II’ from Hungary, as well as ‘Milotai 10’, ‘Chandler’, were significantly different from ‘Alsószentiváni 117’ and ‘Tiszacsécsi 83’ in shell thickness. The Hungarian ‘Esterhazy II’ reached the heaviest dried nut weight; there wasn’t any significant difference in this parameter among the study's varieties. The Swiss ‘Esterhazy II’ and ‘Esterhazy kesei’ had the heaviest kernel weight. Kernel weight of the Austrian ‘Esterhazy II’ differed from the Swiss ‘Esterhazy II’ and ‘Esterhazy kesei’. The Austrian ‘Esterhazy II’ had a significantly smaller cracking rate compared to Swiss ‘Esterhazy II’, ‘Alsószentiváni 117’, and ‘Tiszacsécsi 83’ and a higher rate of halves compared to ‘Esterhazy kesei’ and ‘Alsószentiváni 117’. historic variety local population nut pomology selection SSR analysis Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction The Persian walnut ( Juglans regia L.) is a well-known and widespread nut tree species in the Carpathian Basin, including Hungary. The backyard gardens should have at least one walnut tree in the countryside. This nut tree species might be native to the Pannonian basin, and this population was mixed with other populations (located in Anatolia) through human-mediated activity (Pollegioni et al., 2015 , 2017 , Vahdati 2014 ), which provides a wide range of variability. Accessions with a certain geographical origin, such as walnut derived from Milota and Tarpa (both villages are from Northeast Hungary), Eszterháza, located in Northwest Hungary (today Eszterháza is part of Fertőd, merged in 1950), as well as from Sebesel and Baia Mare (located in Romania), had good renown on the markets during the 18th century. Furthermore, the relative frequency of genotypes with red kernels was very high in the Western or Southwestern Transdanubia. In Transylvania, it was very frequent to find cluster-bearing genotypes. Others, such as genotypes with stone shell, paper shell, thin shell, soft shell, and large nut size did not have special geographic locations, but were typical for the Pannonian Basin (Dochnahl, 1860 , Schneiders 1899 , Mohácsy – Porpáczy 1951, Porpáczy et al. 1955 ). All previously bred, so-called historic genotypes were lost because of a lack of vegetative propagation. This xenovegetative propagation method started in the 1970s in Hungary; therefore, there are some specimens labelled under historic variety names having different traits on the market. The mindful breeding activity started after the strong winter in 1928/29, when seedlings, imported from France in 1910, were heavily damaged by the frosts during the dormant period. First, the breeders used selection from the local population, because 1,900,000 walnut trees were registered during the fruit-bearing tree data collection in 1935 (Porpáczy et al. 1955 ). This method is still very popular in lot of countries such as in China (Luo et al. 2022 ), India (Sajwan 2022 , Shah et al., 2023 ), Iran (Fallah et al., 2024 ), Nepal (Khanal et al., 2023 ), Uzbekistan (Butkov et al., 2020 ), Türkiye (Keles 2014, Aydemir et al., 2025 kücü et al., 2025 ), Kazahstan (Akca et al., 2020 ), Russian Federation (Sokolova, 2022 ), Serbia (Cercovic et al., 2010, Paunović and Rade, 2023 ), Australia (Sluiter et al., 2014 ), Czech Republic (Pavliuk et al., 2025 ), Romania (Botu et al., 2014 , Iordănescu et al., 2021 ), France (Lheureux et al. 2021 ), and Hungary (Bujdosó et al., 2020 ). During the 1930s, the breeding aims were focused on the adaptation of the trees to the local climate conditions and good nut quality (at least 32 mm in diameter, smooth shell surface with light colour, light kernel colour, at least 50% kernel yield, no aftertaste). Furthermore, it was essential to have tolerance to the fungal diseases, and the homogamy was preferred (Porpáczy et al. 1955 ). Today, homogamy during the blossom period is no longer preferred, but others are accepted by the breeders. Further breeding aims were added to this list, like tolerance to the bacterial diseases (Frutos, 2010 , Sun et al., 2025 ), late leafing (Akca, and Özongun 2004 , Kavosi and Khadivi, 2021 Fallah et al., 2022 , Sutyemez et al., 2022 , Hamidirad et al., 2025 ), lateral bearing (Botu et al. 2010 , 2019 , Bernard et al., 2020 , Rezaei et al., 2020 , Hakimi et al., 2024 ), and good shell structure (Sarikhani et al., 2018 , Sarikhani and Vahdati, 2019 , Rezaei et al., 2020 ), Furthermore, good adaptability to the different environmental factors such as drought tolerance (Lofti et al., 2022, Zheng et al., 2024 , Gao et al., 2025 ), low-temperature stress (Zhang et al. 2020 , Zhao et al., 2024), salt tolerance (Ji et al., 2022 , Zheng et al., 2024 ) is needed. During the early stage of breeding, some candidates were prepared for approval. At that time, a candidate had to pass the DUS examination and the Value of Cultivation and Use Test. This later-mentioned test took a long period (15–30 years), in the case of walnut. Furthermore, novel-bred genotype had to have at least one positive value compared to the reference cultivar. During this period, there were some genotypes under evaluation, such as ‘Alsószentiváni 117’, ‘Milotai 10’, ‘Tiszacsécsi 83’, ‘Fertődi 1’, ‘Eszterhazai II’. Among these, the Esterhazy genotypes appeared with various synonyms (Eszterházi, Eszterházy, Eszterházai, Eszterházy), and are still very popular in Switzerland, Germany, and Austria (Solar et al., 1997 ). Unfortunately, many of the historic walnut genotypes were putatively lost due to the use of generative propagation. In this study, our goal was to evaluate the genotypes/varieties, selected from the local populations, with special regard to of the ‘Esterhazy II’ genotypes. Materials and methods Plant material There were some specimens labelled ‘Esterhazy II’ in the ex situ gene bank collection of the Hungarian University of Agriculture and Life Sciences, but those were not true-to-type ones (Bujdosó et al., 2021 , 2022 ). Continuing this research, we went back to that site, from which this genotype was described and selected. Around Eszterháza (part of Fertőd today), the walnut accessions were checked, and senior colleagues were asked about the true-to-type ‘Esterhazy II’ genotype. Finally, we found one tree, which was identified on the old maps of the trials. Samples were collected to check the nut characteristics and the genetic identity of this tree. To add additional true-to-type ‘Esterhazy II’ specimens, the Nut Tree Working Group of European Fruit Research Institute was asked to provide the requested material. BOKU from Austria, and a Swiss nursery (located in Hörhausen) sent us nut and leaf samples to check and compare them with our selected tree. It is important to mention that we do not have any knowledge about having any ‘Esterhazy II’ in the herbaria now. So, the specimen labelled true-to-type ‘Esterhazy II’ from Hungary (marked as ‘Esterhazy II (H)), and further two true-to-type ‘Esterhazy II’ accessions from Austria (marked as ‘Esterhazy II’ (A)), and Switzerland (marked as ‘Esterhazy II’ (CH)), the most grown varieties, selected from the Hungarian local population, ‘Milotai 10’, ‘Tiszacsécsi 83’ and ‘Alsószentiváni 117’, another Esterhazy-type variety, ‘Esterhazy kesei’, as well as the most grown cultivar on the Earth, the US-bred ‘Chandler’ as control, were added to the trial (Table 1 ). Table 1 Some nut characters of the examined varieties, involved in the trial Name of the cultivar Origin Nut diameter (mm) Nut shape Nut weight (g) Kernel colour Kernel yield (%) Alsószentiváni 117 selected from the Hungarian population 33 to 36 elongated 11 to 14 yellowish brown 48 to 51 Chandler cross between Pedro and UC 56–224 28 to 30 round 13 light yellowish brown 49 Esterhazy II derived from a French population, selected in Hungary 37 to 45 ovate with medium-long tip 13 to 15 ivory white 49 Esterhazy kesei selected from the Hungarian population 35 to 37 ovate 13 to 16 light yellow 45 Milotai 10 selected from the Hungarian population 33 to 35 round 13 to 17 straw yellow 47 to 52 Tiszacsécsi 83 selected from the Hungarian population 32 to 34 elongiated 11 to 14 2 light yellowish brown 48 to 52 sources: Böllersen, ( 2017 ), Szentiványi, P. and Kállay T. ( 2006 ), Ramos, 1998 , Aleta, et al., 2005 , Connell et al., 2010 , Bujdosó et al., 2019 , 2022 . Observed traits The Hungarian samples were from a rainfed experimental orchard was established in Érd, Hungary (lat. 47°20′11″N, long. 18°51′53″E; elevation, 127 m above sea level), in 1990. All trees were grafted on selected J. regia seedlings, and plated in five replications in 10 m inter-row and between the row spacing, trained as a central leader canopy. The Table 2 . contains climate and soil conditions of the different sites. Table 2 Climate and soil conditions of the sites involved in the trial Érd (Hungary) Vienna (Austria) Hörhausen (Switzerland) average yearly temperature (˚C) 11.5 10.2 5.8 average yearly temperature during the growing season (between March and September) (˚C) 18.3 16.9 13.8 average yearly precipitation (mm) 538 550 990 During this research period of 2010 to 2024 the nut tree characters (nut height, nut diameter, nut width, shell thickness, dried nut and kernel weight, kernel yield: rate of weight of halves compared to the whole nut weight, and rate of halves: rate of weight of halves compared to the weight of whole kernel) of 1 kg samples were checked. Genetic analysis To prove the genetic identity of the selected samples, a genetic fingerprinting analysis was conducted applying nuclear microsatellite (or nSSR, nuclear simple sequence repeats) markers. The following 13 markers were selected from the available literature: WGA27, WGA72 (Woeste et al., 2002 ), WGA001, WGA004, WGA009, WGA089, WGA118, WGA202, WGA276, WGA321, WGA331 (Dangl et al., 2005 ) and JR1817, JR6160 (Dang et al., 2016 ). PCR conditions were applied based on the original references. For SSR data analysis, GenAlEx 6.5 software (Peakall and Smouse, 2006, 2012) was used. The probability of identity (P ID ) was calculated for the combination of the 13 analyzed loci, and possible matching genotypes were verified. The Genetic distance (Codom-Genotypic) option was applied for generating a pairwise, individual-by-individual genetic distance matrix. Matrix was used for subsequent PCoA and for constructing UPGMA dendrogram by PAST 4.03 (Hammer et al., 2001). Results First, the genetic identity of the analysed samples was confirmed by the fingerprint analysis. The low value of the P ID index (9.54×10 − 9 ) indicated the high accuracy and resolution of the applied markers. The three different ‘Esterhazy II’ specimens involved in the study shared the same genotype; therefore, they can be considered true replicates of the same historical variety. The other five cultivars represented different genetic backgrounds. The ‘Esterhazy II’ genotype appeared relatively distinct from the other clones in this evaluation (Fig. 1 ). The highest nut height was reached by ‘Chandler’, followed by ‘Milotai 10’, and ‘Esterhazy kesei’. The smallest nut height was measured in the case of ‘Alsószentiváni 117’, ‘Tiszacsécsi 83’, ‘Esterhazy II’ harvested in Austria. Nut height of ‘Chandler’ and ‘Milotai 10’ differed significantly from the ‘Esterhazy II’ from Austria and Switzerland, but not from the Hungarian accession. Regarding the diameter, all measured varieties reached the lowest border of the first grade (32 mm), except the control. The largest nut diameter was measured on ‘Milotai 10’, followed by ‘Esterhazy II’ from Switzerland, ‘Alsószentiváni 117’, and ‘Esterhazy kesei’. The smallest nut diameter was measured on the control, ‘Chandler’. The nut width values were similar for all; the largest width was reached by ‘Alsószentiváni 117’, the smallest one was produced by ‘Esterhazy II’, derived from Austria, and the control. There wasn’t a significant difference in nut diameter and nut width (Fig. 1 ). The shell thickness is important during both mechanical harvesting and the post-harvesting. ‘Esterhazy kesei’ had the thickest shell, followed by ‘Esterhazy II’ from Austria and ‘Milotai 10’. The ‘Alsószentiváni 117’ and ‘Tiszacsécsi 83’ had the softest shell, which had a significant difference from the other observed varieties (Fig. 2 ). The Hungarian ‘Esterhazy II’ produced the highest dried nut weight, followed by ‘Alsószentiváni 117’ and ‘Esterhazy II’ from Switzerland. The lowest dried nut weight was reached by ‘Esterhazy II’, derived from Austria, Tiszacsécsi 83’ and the control. There was no significant difference in this parameter. Regarding the kernel weight, the Hungarian-bred ‘Esterhazy kesei’ and the Swiss ‘Esterhazy II’ samples had the heaviest kernels and differed significantly from the other samples. The smallest weight value was reached by ’Chandler’ (Fig. 3 ). The kernel yield is an important parameter because it shows the harvestable quantity. The ‘Tiszacsécsi 83’ ‘Alsószentiváni 117’, ‘Chandler’, and the Swiss ‘Esterhazy II’ reached the highest values. The lowest was produced by the Austrian ‘Esterhazy II’, which did not reach the minimum 40% in kernel yield. The Swiss ‘Esterhazy II’ Tiszacsécsi 83’, and ‘Alsószentiváni 117’ showed a significant difference from the Austrian one in kernel yield. The cracking rate indicates the rate of halves, which is the most important value on the markets. The Swiss ‘Esterhazy II’ and ‘Chandler’ had the highest rate of halves, followed by the Austrian ‘Esterhazy II’. The lowest value from this parameter was produced by ‘Esterhazy kesei’ and ‘Alsószentiváni 117’; both had a significant difference from the other examined varieties (Fig. 4 ). Discussion It is typical for genotypes, accessions derived from the Carpathian Basin, to have large nut sizes (Bujdosó et al. 2020 ), which was confirmed in this trial. Large nut size is important because the market pays extra for the large nut size categories (premium ≤ 32.0 mm, premium + ≤ 34.0, premium++ ≤ 36.0 mm in diameter). The large nut size of varieties, derived from the Pannonian Basin (Bujdosó et al. 2020 ), correlated well to the heavy dried nut weight, as proven in the trial. Beside these two important traits, the selected ‘Esterhazy II’ specimen has a thin shell, which did not have any significant difference from the approved varieties (Fig. 2 ). However, it cannot be confirmed with certainty that ‘Esterhazy II’ does not have French origin based on this study; it is clearly visible that this genotype stands closer to the Hungarian-bred cultivars ‘Tiszacsécsi 83’ and ‘Alsószentiváni 117’. These two are local selections from Central Hungary (Mezőföld region) and Northeast Hungary (Bereg region), respectively. Based on the literature data and the experience collected from German-speaking countries, the ‘Esterhazy II’ is suitable for small-scale cultivation. Declarations Acknowledgements This work was supported by the Research Excellence Programme of the Hungarian University of Agriculture and Life Sciences. Author contributions Géza Bujdosó, Klára Cseke, and Andreas Spornberger contributed to the study conception and design. Material preparation was performed by Géza Bujdosó, Alina Ratiu, Daniela Noll, and Andreas Spornberger. Data collection and analysis were performed by Géza Bujdosó, Alina Ratiu, and Klára Cseke. The first draft of the manuscript was written by Géza Bujdosó and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Funding none Data availability Datasets generated and/or analyzed during the current study are available in the general PC under accession number 4/18/2024. Conflict of interest The authors declare no competing interests. Open Access This article is licensed under a Creative Com mons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Crea tive Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. 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Journal of Pharmacognosy and Phythochemistry 9:3082-3087 Schneiders E (1899) Der neuzeitliche Walnussbaum [The modern walnut tree]. Ulmer Verlag [Publisher], Stuttgart. 15-20 p Shah R, Bakshi P, Jasrotia Wali V, Sharma S, Gupta M, Gupta R, Jamwal M (2023) Comparative morpho-molecular characterization of elite walnut variety Parbat (JWSP-06) with local selections of north-western Himalayan region of Jammu and Kashmir, India. Scientia Hortic-Amsterdam 319. 112176 https://doi.org/10.1016/j.scienta.2023.112176 Sluiter I.R.K, McKenzie L, Mitchell JR. (2014) Walnut rootstock selection for calcareous soils in Southeastern Australia and the potential for expanding the walnut industry in the region. Acta Hortic 1050:105-111 https://doi.org/10.17660/ActaHortic.2014.1050.12 Sokolova, V (2022) Selection of a breeding source material in the collection of the walnut (Juglans regia L.) of the Main Botanical Garden RAS. Pomiculture and small fruits culture in Russia 70:7-18 https://doi.org/10.31676/2073-4948-2022-70-7-18 Solar A, Stampar F, Smole J (1997) The degree of heterodichogamy of some walnut cultivars (Juglans regia l.) in Slovenia. Acta Hortic 442:217-224 https://doi.org/10.17660/ActaHortic.1997.442.32 Sun H, Yali W, Wang W, Zupaila N, Wang L, Ma R (2025) Study on Influencing Factors and Low-Temperature Treatment of Walnut Canker Disease in Hotan County, Xinjiang. Forests 16:728 https://doi.org/10.3390/f16050728 Sutyemez M, Özcan A, Bükücü Ş (2022) A superior genetic source for late leafing in walnut ‘Ahir Nut’. Hortic Sci 49:205-212 https://doi.org/10.17221/22/2022-HORTSCI Szentiványi P, Kállay T (Eds.) Dió.[Persian Walnut]; Mezőgazda Kiadó [Mezőgazda Publisher]: Budapest, Hungary, 2006; p. 66–67. Zhang M-H, Wang J-C, Yang H, Zhang D-Y, Deng P-C, Cui Z-J (2020) Physiological response of Xinjiang wild walnut germplasm to low temperature stress. J Appl Ecol 31:2558-2566 https://doi.org/10.13287/j.1001-9332.202008.002 Zhao H, Luo X, Guo C, Zhang Z, Ma K, Niu J-X, Quan S (2025) Transcriptome and MicroRNA Analysis of Juglans regia in Response to Low-Temperature Stress. Int J Mol Sci 26:1401. https://doi.org/10.3390/ijms26041401 Zheng X, Nie R, Li A, Wu C, Ji X, Tang J, Zhang J (2024) Integrated physio-biochemical and transcriptomic analysis reveals mechanism underlying salt tolerance in walnut. Plant Growth Regul 104:727-743. https://doi.org/10.1007/s10725-024-01193-3 Vahdati K (2014) Traditions and folks for walnut growing around the Silk Road. Acta Hortic1032:19–24 https://doi.org/10.17660/ActaHortic.2014.1032.1 Woeste K, Burns R, Rhodes O, Michler C (2002) Thirty polymorphic nuclear microsatellite loci from black walnut. J Hered 93:58-60 https://doi.org/10.1093/jhered/93.1.58 Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7068639","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Short Report","associatedPublications":[],"authors":[{"id":484739140,"identity":"d3c64ca4-8bfa-4c00-8138-4891be83bf77","order_by":0,"name":"Géza Bujdosó","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/0lEQVRIiWNgGAWjYBACAwaGBAk47wMDAw+UeYA4LYwzIFoYGwhoYYBrYYZagV+LuUTCwxsf/tgwyLu3P/xs23ZHhkHs8PMHHxjuJDbg0GI5IyHZcmZbGoPhmQPJ0rltz3gYpNMMG2cwPMOpxeBGQpo0b8NhBsMZCQeAWg7z2N9OMGzmYTiMXwvPH6CW+Q+bf1sCtTBIp39s/kNQC9thBnkJZjZpRrCWHMNmBjxaLHsegP3CY8CTxmbZcw6spXBmj8FhY1xazNlzEkEhJifffvzxjR9lh+2BDtvw4UfFYVlcWoBxlwAmDQ6gOhineiBgh6iVx23oKBgFo2AUjHQAALppW2ovR56VAAAAAElFTkSuQmCC","orcid":"","institution":"Hungarian University of Agriculture and Life Sciences","correspondingAuthor":true,"prefix":"","firstName":"Géza","middleName":"","lastName":"Bujdosó","suffix":""},{"id":484739141,"identity":"585be816-e397-4db8-b0a3-fc50d1bd9d71","order_by":1,"name":"Alina Ratiu","email":"","orcid":"","institution":"Hungarian University of Agriculture and Life Sciences","correspondingAuthor":false,"prefix":"","firstName":"Alina","middleName":"","lastName":"Ratiu","suffix":""},{"id":484739142,"identity":"8706be51-92ca-4d34-80b1-4b39b148982d","order_by":2,"name":"Andreas Spornberger","email":"","orcid":"","institution":"BOKU University","correspondingAuthor":false,"prefix":"","firstName":"Andreas","middleName":"","lastName":"Spornberger","suffix":""},{"id":484739143,"identity":"0cbac002-9d2d-44ed-a7fb-32cb61d4e1aa","order_by":3,"name":"Daniela Noll","email":"","orcid":"","institution":"BOKU University","correspondingAuthor":false,"prefix":"","firstName":"Daniela","middleName":"","lastName":"Noll","suffix":""},{"id":484739144,"identity":"ff9781ff-339d-4dbe-84ae-12be7dc8dc88","order_by":4,"name":"Klára Cseke","email":"","orcid":"","institution":"University of Sopron","correspondingAuthor":false,"prefix":"","firstName":"Klára","middleName":"","lastName":"Cseke","suffix":""}],"badges":[],"createdAt":"2025-07-07 20:38:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7068639/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7068639/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10722-025-02590-x","type":"published","date":"2025-08-07T15:57:33+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":86759367,"identity":"a5dd69ac-49b3-4666-9455-7f27d41fb75f","added_by":"auto","created_at":"2025-07-15 10:01:42","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":43120,"visible":true,"origin":"","legend":"\u003cp\u003eNut height (NH), nut diameter (ND), and nut width (NW) in mm of the measured varieties (SD\u003csub\u003e5%NH\u003c/sub\u003e= 5.0, SD\u003csub\u003e5%ND\u003c/sub\u003e= 1.5, SD\u003csub\u003e5%NW\u003c/sub\u003e= 1.2)\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7068639/v1/8cf30474388ac6e67d5e01b4.png"},{"id":86759368,"identity":"015f5183-3969-4b18-8a27-ec877d8283f0","added_by":"auto","created_at":"2025-07-15 10:01:42","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":24255,"visible":true,"origin":"","legend":"\u003cp\u003eShell thickness of the studied varieties (SD\u003csub\u003e5%\u003c/sub\u003e= 0.25)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7068639/v1/e9bdd47c9e8a5777edc52ad3.png"},{"id":86759380,"identity":"4d4d8d28-cf33-49b1-be1f-e0b1d12aa763","added_by":"auto","created_at":"2025-07-15 10:01:43","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":42804,"visible":true,"origin":"","legend":"\u003cp\u003eDried nut weight (DNW) and kernel weight (KW) of the studied varieties (SD\u003csub\u003e5%DNW\u003c/sub\u003e= 1.4, SD\u003csub\u003e5%KW\u003c/sub\u003e= 0.7)\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7068639/v1/21db0406056bd65adb4c08b7.png"},{"id":86759369,"identity":"a5840c4a-1d04-494f-8635-1a78429d6cf0","added_by":"auto","created_at":"2025-07-15 10:01:42","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":37538,"visible":true,"origin":"","legend":"\u003cp\u003eCracking rate (CR) and ratio of halves (RH) of the studied varieties (SD\u003csub\u003e5%CR\u003c/sub\u003e= 6.5, SD\u003csub\u003e5%RH\u003c/sub\u003e= 8.0)\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7068639/v1/b79636d37524603da6a78cf0.png"},{"id":88814334,"identity":"e55fbd1e-b706-42da-986d-27471e2813e6","added_by":"auto","created_at":"2025-08-11 16:09:39","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":622682,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7068639/v1/4496b875-07bf-49d2-b6b8-d57b2527cb33.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Evaluation of ‘Esterhazy II’ Persian walnut (Juglans regia L.) genotypes from Hungary, Austria, and Switzerland","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe Persian walnut (\u003cem\u003eJuglans regia\u003c/em\u003e L.) is a well-known and widespread nut tree species in the Carpathian Basin, including Hungary. The backyard gardens should have at least one walnut tree in the countryside. This nut tree species might be native to the Pannonian basin, and this population was mixed with other populations (located in Anatolia) through human-mediated activity (Pollegioni et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2015\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2017\u003c/span\u003e, Vahdati \u003cspan citationid=\"CR57\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), which provides a wide range of variability. Accessions with a certain geographical origin, such as walnut derived from Milota and Tarpa (both villages are from Northeast Hungary), Eszterh\u0026aacute;za, located in Northwest Hungary (today Eszterh\u0026aacute;za is part of Fertőd, merged in 1950), as well as from Sebesel and Baia Mare (located in Romania), had good renown on the markets during the 18th century. Furthermore, the relative frequency of genotypes with red kernels was very high in the Western or Southwestern Transdanubia. In Transylvania, it was very frequent to find cluster-bearing genotypes. Others, such as genotypes with stone shell, paper shell, thin shell, soft shell, and large nut size did not have special geographic locations, but were typical for the Pannonian Basin (Dochnahl, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e1860\u003c/span\u003e, Schneiders \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e1899\u003c/span\u003e, Moh\u0026aacute;csy \u0026ndash; Porp\u0026aacute;czy 1951, Porp\u0026aacute;czy et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e1955\u003c/span\u003e). All previously bred, so-called historic genotypes were lost because of a lack of vegetative propagation. This xenovegetative propagation method started in the 1970s in Hungary; therefore, there are some specimens labelled under historic variety names having different traits on the market.\u003c/p\u003e\u003cp\u003eThe mindful breeding activity started after the strong winter in 1928/29, when seedlings, imported from France in 1910, were heavily damaged by the frosts during the dormant period. First, the breeders used selection from the local population, because 1,900,000 walnut trees were registered during the fruit-bearing tree data collection in 1935 (Porp\u0026aacute;czy et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e1955\u003c/span\u003e). This method is still very popular in lot of countries such as in China (Luo et al. \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), India (Sajwan \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Shah et al., \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), Iran (Fallah et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), Nepal (Khanal et al., \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), Uzbekistan (Butkov et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), T\u0026uuml;rkiye (Keles 2014, Aydemir et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2025\u003c/span\u003ek\u0026uuml;c\u0026uuml; et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2025\u003c/span\u003e), Kazahstan (Akca et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), Russian Federation (Sokolova, \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), Serbia (Cercovic et al., 2010, Paunović and Rade, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), Australia (Sluiter et al., \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), Czech Republic (Pavliuk et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2025\u003c/span\u003e), Romania (Botu et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2014\u003c/span\u003e, Iordănescu et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), France (Lheureux et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), and Hungary (Bujdos\u0026oacute; et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eDuring the 1930s, the breeding aims were focused on the adaptation of the trees to the local climate conditions and good nut quality (at least 32 mm in diameter, smooth shell surface with light colour, light kernel colour, at least 50% kernel yield, no aftertaste). Furthermore, it was essential to have tolerance to the fungal diseases, and the homogamy was preferred (Porp\u0026aacute;czy et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e1955\u003c/span\u003e). Today, homogamy during the blossom period is no longer preferred, but others are accepted by the breeders. Further breeding aims were added to this list, like tolerance to the bacterial diseases (Frutos, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2010\u003c/span\u003e, Sun et al., \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2025\u003c/span\u003e), late leafing (Akca, and \u0026Ouml;zongun \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2004\u003c/span\u003e, Kavosi and Khadivi, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2021\u003c/span\u003e Fallah et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Sutyemez et al., \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Hamidirad et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e), lateral bearing (Botu et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2010\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2019\u003c/span\u003e, Bernard et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2020\u003c/span\u003e, Rezaei et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2020\u003c/span\u003e, Hakimi et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), and good shell structure (Sarikhani et al., \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2018\u003c/span\u003e, Sarikhani and Vahdati, \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2019\u003c/span\u003e, Rezaei et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), Furthermore, good adaptability to the different environmental factors such as drought tolerance (Lofti et al., 2022, Zheng et al., \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2024\u003c/span\u003e, Gao et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2025\u003c/span\u003e), low-temperature stress (Zhang et al. \u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e2020\u003c/span\u003e, Zhao et al., 2024), salt tolerance (Ji et al., \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Zheng et al., \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) is needed.\u003c/p\u003e\u003cp\u003eDuring the early stage of breeding, some candidates were prepared for approval. At that time, a candidate had to pass the DUS examination and the Value of Cultivation and Use Test. This later-mentioned test took a long period (15\u0026ndash;30 years), in the case of walnut. Furthermore, novel-bred genotype had to have at least one positive value compared to the reference cultivar. During this period, there were some genotypes under evaluation, such as \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;, \u0026lsquo;Milotai 10\u0026rsquo;, \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo;, \u0026lsquo;Fertődi 1\u0026rsquo;, \u0026lsquo;Eszterhazai II\u0026rsquo;. Among these, the Esterhazy genotypes appeared with various synonyms (Eszterh\u0026aacute;zi, Eszterh\u0026aacute;zy, Eszterh\u0026aacute;zai, Eszterh\u0026aacute;zy), and are still very popular in Switzerland, Germany, and Austria (Solar et al., \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e1997\u003c/span\u003e). Unfortunately, many of the historic walnut genotypes were putatively lost due to the use of generative propagation.\u003c/p\u003e\u003cp\u003eIn this study, our goal was to evaluate the genotypes/varieties, selected from the local populations, with special regard to of the \u0026lsquo;Esterhazy II\u0026rsquo; genotypes.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e\u003cb\u003ePlant material\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThere were some specimens labelled \u0026lsquo;Esterhazy II\u0026rsquo; in the ex situ gene bank collection of the Hungarian University of Agriculture and Life Sciences, but those were not true-to-type ones (Bujdos\u0026oacute; et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Continuing this research, we went back to that site, from which this genotype was described and selected. Around Eszterh\u0026aacute;za (part of Fertőd today), the walnut accessions were checked, and senior colleagues were asked about the true-to-type \u0026lsquo;Esterhazy II\u0026rsquo; genotype. Finally, we found one tree, which was identified on the old maps of the trials. Samples were collected to check the nut characteristics and the genetic identity of this tree. To add additional true-to-type \u0026lsquo;Esterhazy II\u0026rsquo; specimens, the Nut Tree Working Group of European Fruit Research Institute was asked to provide the requested material. BOKU from Austria, and a Swiss nursery (located in H\u0026ouml;rhausen) sent us nut and leaf samples to check and compare them with our selected tree. It is important to mention that we do not have any knowledge about having any \u0026lsquo;Esterhazy II\u0026rsquo; in the herbaria now. So, the specimen labelled true-to-type \u0026lsquo;Esterhazy II\u0026rsquo; from Hungary (marked as \u0026lsquo;Esterhazy II (H)), and further two true-to-type \u0026lsquo;Esterhazy II\u0026rsquo; accessions from Austria (marked as \u0026lsquo;Esterhazy II\u0026rsquo; (A)), and Switzerland (marked as \u0026lsquo;Esterhazy II\u0026rsquo; (CH)), the most grown varieties, selected from the Hungarian local population, \u0026lsquo;Milotai 10\u0026rsquo;, \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo; and \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;, another Esterhazy-type variety, \u0026lsquo;Esterhazy kesei\u0026rsquo;, as well as the most grown cultivar on the Earth, the US-bred \u0026lsquo;Chandler\u0026rsquo; as control, were added to the trial (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSome nut characters of the examined varieties, involved in the trial\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eName of the cultivar\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOrigin\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNut diameter (mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eNut shape\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eNut weight (g)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eKernel colour\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eKernel yield (%)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAls\u0026oacute;szentiv\u0026aacute;ni 117\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eselected from the Hungarian population\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e33 to 36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eelongated\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11 to 14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eyellowish brown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e48 to 51\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eChandler\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ecross between Pedro and UC 56\u0026ndash;224\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e28 to 30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eround\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003elight yellowish brown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e49\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEsterhazy II\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ederived from a French population, selected in Hungary\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e37 to 45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eovate with medium-long tip\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13 to 15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eivory white\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e49\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEsterhazy kesei\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eselected from the Hungarian population\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e35 to 37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eovate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13 to 16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003elight yellow\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMilotai 10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eselected from the Hungarian population\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e33 to 35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eround\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13 to 17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003estraw yellow\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e47 to 52\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTiszacs\u0026eacute;csi 83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eselected from the Hungarian population\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e32 to 34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eelongiated\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11 to 14\u003c/p\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003elight yellowish brown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e48 to 52\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003esources: B\u0026ouml;llersen, (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2017\u003c/span\u003e), Szentiv\u0026aacute;nyi, P. and K\u0026aacute;llay T. (\u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e2006\u003c/span\u003e), Ramos, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e1998\u003c/span\u003e, Aleta, et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2005\u003c/span\u003e, Connell et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2010\u003c/span\u003e, Bujdos\u0026oacute; et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2019\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2022\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cb\u003eObserved traits\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe Hungarian samples were from a rainfed experimental orchard was established in \u0026Eacute;rd, Hungary (lat. 47\u0026deg;20\u0026prime;11\u0026Prime;N, long. 18\u0026deg;51\u0026prime;53\u0026Prime;E; elevation, 127 m above sea level), in 1990. All trees were grafted on selected \u003cem\u003eJ. regia\u003c/em\u003e seedlings, and plated in five replications in 10 m inter-row and between the row spacing, trained as a central leader canopy. The Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. contains climate and soil conditions of the different sites.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eClimate and soil conditions of the sites involved in the trial\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026Eacute;rd\u003c/p\u003e\u003cp\u003e(Hungary)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eVienna\u003c/p\u003e\u003cp\u003e(Austria)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eH\u0026ouml;rhausen\u003c/p\u003e\u003cp\u003e(Switzerland)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eaverage yearly temperature\u003c/p\u003e\u003cp\u003e(˚C)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e11.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e10.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eaverage yearly temperature during the growing season (between March and September)\u003c/p\u003e\u003cp\u003e(˚C)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e18.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eaverage yearly precipitation\u003c/p\u003e\u003cp\u003e(mm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e538\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e550\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e990\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eDuring this research period of 2010 to 2024 the nut tree characters (nut height, nut diameter, nut width, shell thickness, dried nut and kernel weight, kernel yield: rate of weight of halves compared to the whole nut weight, and rate of halves: rate of weight of halves compared to the weight of whole kernel) of 1 kg samples were checked.\u003c/p\u003e\u003cp\u003e\u003cb\u003eGenetic analysis\u003c/b\u003e\u003c/p\u003e\u003cp\u003eTo prove the genetic identity of the selected samples, a genetic fingerprinting analysis was conducted applying nuclear microsatellite (or nSSR, nuclear simple sequence repeats) markers. The following 13 markers were selected from the available literature: WGA27, WGA72 (Woeste et al., \u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e2002\u003c/span\u003e), WGA001, WGA004, WGA009, WGA089, WGA118, WGA202, WGA276, WGA321, WGA331 (Dangl et al., \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2005\u003c/span\u003e) and JR1817, JR6160 (Dang et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). PCR conditions were applied based on the original references.\u003c/p\u003e\u003cp\u003eFor SSR data analysis, GenAlEx 6.5 software (Peakall and Smouse, 2006, 2012) was used. The probability of identity (P\u003csub\u003eID\u003c/sub\u003e) was calculated for the combination of the 13 analyzed loci, and possible matching genotypes were verified. The Genetic distance (Codom-Genotypic) option was applied for generating a pairwise, individual-by-individual genetic distance matrix. Matrix was used for subsequent PCoA and for constructing UPGMA dendrogram by PAST 4.03 (Hammer et al., 2001).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eFirst, the genetic identity of the analysed samples was confirmed by the fingerprint analysis. The low value of the P\u003csub\u003eID\u003c/sub\u003e index (9.54\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;9\u003c/sup\u003e) indicated the high accuracy and resolution of the applied markers. The three different \u0026lsquo;Esterhazy II\u0026rsquo; specimens involved in the study shared the same genotype; therefore, they can be considered true replicates of the same historical variety. The other five cultivars represented different genetic backgrounds. The \u0026lsquo;Esterhazy II\u0026rsquo; genotype appeared relatively distinct from the other clones in this evaluation (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eThe highest nut height was reached by \u0026lsquo;Chandler\u0026rsquo;, followed by \u0026lsquo;Milotai 10\u0026rsquo;, and \u0026lsquo;Esterhazy kesei\u0026rsquo;. The smallest nut height was measured in the case of \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;, \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo;, \u0026lsquo;Esterhazy II\u0026rsquo; harvested in Austria. Nut height of \u0026lsquo;Chandler\u0026rsquo; and \u0026lsquo;Milotai 10\u0026rsquo; differed significantly from the \u0026lsquo;Esterhazy II\u0026rsquo; from Austria and Switzerland, but not from the Hungarian accession.\u003c/p\u003e\n\u003cp\u003eRegarding the diameter, all measured varieties reached the lowest border of the first grade (32 mm), except the control. The largest nut diameter was measured on \u0026lsquo;Milotai 10\u0026rsquo;, followed by \u0026lsquo;Esterhazy II\u0026rsquo; from Switzerland, \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;, and \u0026lsquo;Esterhazy kesei\u0026rsquo;. The smallest nut diameter was measured on the control, \u0026lsquo;Chandler\u0026rsquo;.\u003c/p\u003e\n\u003cp\u003eThe nut width values were similar for all; the largest width was reached by \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;, the smallest one was produced by \u0026lsquo;Esterhazy II\u0026rsquo;, derived from Austria, and the control. There wasn\u0026rsquo;t a significant difference in nut diameter and nut width (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eThe shell thickness is important during both mechanical harvesting and the post-harvesting. \u0026lsquo;Esterhazy kesei\u0026rsquo; had the thickest shell, followed by \u0026lsquo;Esterhazy II\u0026rsquo; from Austria and \u0026lsquo;Milotai 10\u0026rsquo;. The \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo; and \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo; had the softest shell, which had a significant difference from the other observed varieties (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eThe Hungarian \u0026lsquo;Esterhazy II\u0026rsquo; produced the highest dried nut weight, followed by \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo; and \u0026lsquo;Esterhazy II\u0026rsquo; from Switzerland. The lowest dried nut weight was reached by \u0026lsquo;Esterhazy II\u0026rsquo;, derived from Austria, Tiszacs\u0026eacute;csi 83\u0026rsquo; and the control. There was no significant difference in this parameter.\u003c/p\u003e\n\u003cp\u003eRegarding the kernel weight, the Hungarian-bred \u0026lsquo;Esterhazy kesei\u0026rsquo; and the Swiss \u0026lsquo;Esterhazy II\u0026rsquo; samples had the heaviest kernels and differed significantly from the other samples. The smallest weight value was reached by \u0026rsquo;Chandler\u0026rsquo; (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eThe kernel yield is an important parameter because it shows the harvestable quantity. The \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo; \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;, \u0026lsquo;Chandler\u0026rsquo;, and the Swiss \u0026lsquo;Esterhazy II\u0026rsquo; reached the highest values. The lowest was produced by the Austrian \u0026lsquo;Esterhazy II\u0026rsquo;, which did not reach the minimum 40% in kernel yield. The Swiss \u0026lsquo;Esterhazy II\u0026rsquo; Tiszacs\u0026eacute;csi 83\u0026rsquo;, and \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo; showed a significant difference from the Austrian one in kernel yield.\u003c/p\u003e\n\u003cp\u003eThe cracking rate indicates the rate of halves, which is the most important value on the markets. The Swiss \u0026lsquo;Esterhazy II\u0026rsquo; and \u0026lsquo;Chandler\u0026rsquo; had the highest rate of halves, followed by the Austrian \u0026lsquo;Esterhazy II\u0026rsquo;. The lowest value from this parameter was produced by \u0026lsquo;Esterhazy kesei\u0026rsquo; and \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;; both had a significant difference from the other examined varieties (Fig. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIt is typical for genotypes, accessions derived from the Carpathian Basin, to have large nut sizes (Bujdos\u0026oacute; et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), which was confirmed in this trial. Large nut size is important because the market pays extra for the large nut size categories (premium\u0026thinsp;\u0026le;\u0026thinsp;32.0 mm, premium\u0026thinsp;+\u0026thinsp;\u0026le;\u0026thinsp;34.0, premium++ \u0026le; 36.0 mm in diameter). The large nut size of varieties, derived from the Pannonian Basin (Bujdos\u0026oacute; et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), correlated well to the heavy dried nut weight, as proven in the trial. Beside these two important traits, the selected \u0026lsquo;Esterhazy II\u0026rsquo; specimen has a thin shell, which did not have any significant difference from the approved varieties (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eHowever, it cannot be confirmed with certainty that \u0026lsquo;Esterhazy II\u0026rsquo; does not have French origin based on this study; it is clearly visible that this genotype stands closer to the Hungarian-bred cultivars \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo; and \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;. These two are local selections from Central Hungary (Mezőf\u0026ouml;ld region) and Northeast Hungary (Bereg region), respectively.\u003c/p\u003e\u003cp\u003eBased on the literature data and the experience collected from German-speaking countries, the \u0026lsquo;Esterhazy II\u0026rsquo; is suitable for small-scale cultivation.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by the Research Excellence Programme of the Hungarian University of Agriculture and Life Sciences.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eG\u0026eacute;za Bujdos\u0026oacute;, Kl\u0026aacute;ra Cseke, and Andreas Spornberger contributed to the study conception and design. Material preparation was performed by G\u0026eacute;za Bujdos\u0026oacute;, Alina Ratiu, Daniela Noll, and Andreas Spornberger. Data collection and analysis were performed by G\u0026eacute;za Bujdos\u0026oacute;, Alina Ratiu, and Kl\u0026aacute;ra Cseke. The first draft of the manuscript was written by G\u0026eacute;za Bujdos\u0026oacute; and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e none\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDatasets generated and/or analyzed during the current study are available in the general PC under accession number 4/18/2024.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOpen Access\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThis article is licensed under a Creative Com mons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Crea tive Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article\u0026rsquo;s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article\u0026rsquo;s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAkca Y, \u0026Ouml;zongun Ş (2004) Selection of late leafing, late flowering, laterally fruitful walnut (Juglans regia) types in Turkey. 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Int J Mol Sci 26:1401. https://doi.org/10.3390/ijms26041401\u003c/li\u003e\n\u003cli\u003eZheng X, Nie R, Li A, Wu C, Ji X, Tang J, Zhang J (2024) Integrated physio-biochemical and transcriptomic analysis reveals mechanism underlying salt tolerance in walnut. Plant Growth Regul 104:727-743. https://doi.org/10.1007/s10725-024-01193-3\u003c/li\u003e\n\u003cli\u003eVahdati K (2014) Traditions and folks for walnut growing around the Silk Road. Acta Hortic1032:19\u0026ndash;24 https://doi.org/10.17660/ActaHortic.2014.1032.1\u003c/li\u003e\n\u003cli\u003eWoeste K, Burns R, Rhodes O, Michler C (2002) Thirty polymorphic nuclear microsatellite loci from black walnut. J Hered 93:58-60 https://doi.org/10.1093/jhered/93.1.58\u003cstrong\u003e\u003c/strong\u003e\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"genetic-resources-and-crop-evolution","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"gres","sideBox":"Learn more about [Genetic Resources and Crop Evolution](https://www.springer.com/journal/10722)","snPcode":"10722","submissionUrl":"https://submission.nature.com/new-submission/10722/3","title":"Genetic Resources and Crop Evolution","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"historic variety, local population, nut pomology, selection, SSR analysis","lastPublishedDoi":"10.21203/rs.3.rs-7068639/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7068639/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe historic Persian walnut genotype, known as \u0026lsquo;Esterhazy II\u0026rsquo; and derived from Hungary, is well-known in the German-speaking countries; however, there are only a few specimens showing significant variability in traits in its native country. In this current study, the aim was to evaluate our genotype, labelled \u0026lsquo;Esterhazy II\u0026rsquo;, which is planted in the ex-situ gene bank of the Hungarian University of Agriculture and Life Sciences, and compare it to other true-to-type ones. During the examination, the SSR analysis confirmed that the Hungarian \u0026lsquo;Esterhazy II\u0026rsquo; is exactly identical to the true-to-type Austrian and Swiss varieties. The Austrian and the Swiss \u0026lsquo;Esterhazy II\u0026rsquo; differed significantly in nut height from the control \u0026lsquo;Chandler\u0026rsquo;. There was no further significant difference in the nut parameters. All Esterhazy genotypes, except \u0026lsquo;Esterhazy II\u0026rsquo; from Hungary, as well as \u0026lsquo;Milotai 10\u0026rsquo;, \u0026lsquo;Chandler\u0026rsquo;, were significantly different from \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo; and \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo; in shell thickness. The Hungarian \u0026lsquo;Esterhazy II\u0026rsquo; reached the heaviest dried nut weight; there wasn\u0026rsquo;t any significant difference in this parameter among the study's varieties. The Swiss \u0026lsquo;Esterhazy II\u0026rsquo; and \u0026lsquo;Esterhazy kesei\u0026rsquo; had the heaviest kernel weight. Kernel weight of the Austrian \u0026lsquo;Esterhazy II\u0026rsquo; differed from the Swiss \u0026lsquo;Esterhazy II\u0026rsquo; and \u0026lsquo;Esterhazy kesei\u0026rsquo;. The Austrian \u0026lsquo;Esterhazy II\u0026rsquo; had a significantly smaller cracking rate compared to Swiss \u0026lsquo;Esterhazy II\u0026rsquo;, \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;, and \u0026lsquo;Tiszacs\u0026eacute;csi 83\u0026rsquo; and a higher rate of halves compared to \u0026lsquo;Esterhazy kesei\u0026rsquo; and \u0026lsquo;Als\u0026oacute;szentiv\u0026aacute;ni 117\u0026rsquo;.\u003c/p\u003e","manuscriptTitle":"Evaluation of ‘Esterhazy II’ Persian walnut (Juglans regia L.) genotypes from Hungary, Austria, and Switzerland","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-15 10:01:38","doi":"10.21203/rs.3.rs-7068639/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-07-20T17:24:04+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-20T15:24:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"317736714899938218764669783940125233224","date":"2025-07-16T09:12:01+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-13T19:19:20+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-13T12:41:10+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-12T09:40:55+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"154380911504460786417502714436473591522","date":"2025-07-11T15:44:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"108459004137072511531329056053952508258","date":"2025-07-11T10:34:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"3779337721021212423680539860679627079","date":"2025-07-11T09:41:46+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-11T09:25:35+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-09T06:59:15+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-09T06:58:52+00:00","index":"","fulltext":""},{"type":"submitted","content":"Genetic Resources and Crop Evolution","date":"2025-07-07T20:26:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"genetic-resources-and-crop-evolution","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"gres","sideBox":"Learn more about [Genetic Resources and Crop Evolution](https://www.springer.com/journal/10722)","snPcode":"10722","submissionUrl":"https://submission.nature.com/new-submission/10722/3","title":"Genetic Resources and Crop Evolution","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"703b8ab5-fb20-4b93-bd0c-39d90bb51375","owner":[],"postedDate":"July 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-11T16:07:36+00:00","versionOfRecord":{"articleIdentity":"rs-7068639","link":"https://doi.org/10.1007/s10722-025-02590-x","journal":{"identity":"genetic-resources-and-crop-evolution","isVorOnly":false,"title":"Genetic Resources and Crop Evolution"},"publishedOn":"2025-08-07 15:57:33","publishedOnDateReadable":"August 7th, 2025"},"versionCreatedAt":"2025-07-15 10:01:38","video":"","vorDoi":"10.1007/s10722-025-02590-x","vorDoiUrl":"https://doi.org/10.1007/s10722-025-02590-x","workflowStages":[]},"version":"v1","identity":"rs-7068639","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7068639","identity":"rs-7068639","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}