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Background Common walnut (Juglans regia L.) is one of the top four most consumed nuts in the world due to its health benefits and pleasant taste. Despite its economic importance, the evolutionary history and genetic control of its adaptation and agronomic traits remain largely unexplored. Results We report a comprehensive walnut genomic variation map based on whole-genome resequencing of 815 walnut accessions. Evolutionary analyses suggest that Chinese J. regia diverged from J. sigillata with extensive hybridizations after the split of the two species. In contrast to annual crops, the genetic diversity and heterozygous deleterious mutations of Chinese common walnut trees have continued to increase during the improvement process. Selective sweep analyses identify 902 genes uniquely selected in the improved common walnut compared to its progenitor population. Five major-effect loci are identified to be involved in walnut adaptations to temperature, precipitation, and altitude. Genome-wide association studies reveal 27 genomic loci responsible for 18 important agronomic traits, among which JrFAD2 and JrANR are the potentially major-effect causative genes controlling linoleic acid content and color of the endopleura of the nut, respectively. Conclusions The largest genomic resource for walnuts to date has been generated and explored in this study, unveiling their evolutionary history and cracking the genetic code for agronomic traits and environmental adaptation of this economically crucial crop tree.

A diverse collection of Juglans species and hybrids with potential to serve as walnut rootstocks was evaluated to identify resistance to Phytophthora cinnamomi, a destructive pathogen affecting commercial production of Persian walnuts worldwide. A total of 35 Juglans genotypes, comprising hybrids and Juglans microcarpa, plus three Juglans regia genotypes as comparison, were inoculated during two seasons (spring and autumn) for 3 years, with two isolates of P. cinnamomi. Inoculations were carried out on excised shoots of the different genotypes by replacing a bark disk with a P. cinnamomi culture plug. After incubation, necrosis length caused by the pathogen was measured. Data were collected and statistically analyzed with generalized linear mixed models. This work pointed out a seasonal influence on some Juglans genotype response to P. cinnamomi: both hybrids and J. microcarpa groups were significantly less sensitive in autumn compared with spring (P = 0.0006), thus this condition must be considered when selecting Juglans for resistance to this pathogen. Three genotypes of J. regia, known for its susceptibility to P. cinnamomi, were used as comparison. Results show good levels of resistance to P. cinnamomi in J. microcarpa genotypes, confirming literature results. Among J. microcarpa genotypes, the Jmi03 is quite promising for its in vitro propagation. A number of Juglans hybrids, H5/18, 7/28,8/29, 10/43, and 6/22, showed significantly higher levels of resistance to P. cinnamomi, compared with susceptible J. regia genotypes. Evaluation, in naturally infected fields, of clonal genotypes and seedling-progenies of resistant genotypes, grafted with commercial walnut varieties, is currently under way and will provide additional information for successful usage.

Graphical abstract, Highlights • Juglans regia L. fruit is commonly used as nutraceuticals especially for development of brain tissue. • Isoprenaline administration produces oxidative damage, reduced antioxidant status and cholinergic crisis along with histopathological alterations in rat brain. • Hull extract administration reduced the lipid and protein peroxidation, restored antioxidant status and histopathological changes in brain induced by isoprenaline., The study was aimed at assessing isoprenaline (ISO) induced oxidative damage in brain of Wistar rats and its protection by hydroethanolic hull extract of Juglans regia. Administration of ISO significantly increases catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), malondialdehyde (MDA) and advanced oxidation protein product (AOPP) levels and significantly reduced activities of antioxidant status (TAS), total thiols (TTH), acetylcholinesterase (AChE), arylesterase (AE), and glutathione peroxidase (GPx) in rat brain. Histopathologically, neuronal degeneration, spongiosis and gliosis were seen in cerebral cortex after ISO administration. Pretreatment with hull extract restored TAS, TTH, AChE, CAT and SOD values. Additionally, significant reductions were noted in levels of MDA, AOPP, and severity of histomorphological changes in cerebral cortex following hull extract treatment. Altered antioxidant biomarkers along with histopathological changes indicate oxidative injury in rat brain following ISO administration. Repeated administration of J. regia hull extract demonstrating presence of neuroprotective properties against ISO induced oxidative damage in rat brain.

Background Walnut is an important economic tree species with prominent economic value and ecological functions. However, in recent years, walnuts have become susceptible to drought stress, resulting in a decline in comprehensive benefits. Therefore, it is necessary to identify the regulatory molecular mechanism associated with walnut response to drought. In many plants, ethylene responsive factor (ERF) gene family plays important roles in response to biotic and abiotic stress, especial drought. Therefore, the identification and characterisation of walnut ERF genes will benefit walnut with regard to the clarification of drought response mechanism as well as the management, production, and quality of plantations. Methods ‘ERF’ was compared against the walnut transcriptome, and the JrERFs with a complete open reading frame (ORF) were identified by ORF Finder. The molecular weights, amino acid residues, and theoretical isoelectric point (pI) were predicted by ExPASy. The distribution of JrERFs in chromosome locations was determined based on walnut genome data from NCBI. The intron-exon structures and conserved domains were analysed using Gene Structure Display Server 2.0 and CD-Search, accordingly. Multi-sequence alignment and a phylogenetic tree were constructed by ClustalX2.1 and MEGA7, respectively. The conserved motifs were acquired using MEME. Total RNA was isolated using the cetyltrimethylammonium ammonium bromide (CTAB) method (Yang et al., 2018). Gene expression was determined by using real-time quantitative polymerase chain reaction (qRT-PCR) analysis and calculated according to the 2−ΔΔCT method (Livak & Schmittgen, 2001). Results A total of 44 JrERFs were identified from the walnut transcriptome, whose ORFs were 450–1,239 bp in length. The molecular weights of the JrERF proteins (consisting 149–412 amino acids) were 16.81–43.71 kDa, with pI ranging from 4.8 (JrERF11) to 9.89 (JrERF03). The JrERFs can be divided into six groups (B1–B6), and among the groups, B6 contained the most number of members. Each JrERF contained 1–6 motifs and each motif comprised 9–50 amino acids. Among the motifs, motif1, motif2, and motif3 were the most abundant. More than 40% of JrERFs were up-regulated continuously when subjected to ethephon (ETH), PEG6000, and PEG6000+ETH treatments. Of all the JrERFs, JrERF11 showed the highest expression. Therefore, we conclude that walnut ERF genes are highly conserved and involved in the regulation of drought response in the presence of ETH. JrERFs are possibly important candidate genes for molecular breeding; hence, the findings of this study provides the theoretical basis for further investigation of ERF genes in walnut and other species.

The transcription factor WRKY is widely distributed in the plant kingdom, playing a significant role in plant growth, development and response to stresses. Walnut is an economically important temperate tree species valued for both its edible nuts and high-quality wood, and its response to various stresses is an important factor that determines the quality of its fruit. However, in walnut trees themselves, information about the WRKY gene family remains scarce. In this paper, we perform a comprehensive study of the WRKY gene family in walnut. In total, we identified 103 WRKY genes in the common walnut that are clustered into 4 groups and distributed on 14 chromosomes. The conserved domains all contained a WRKY domain, and motif 2 was observed in most WRKYs, suggesting a high degree of conservation and similar functions within each subfamily. However, gene structure was significantly differentiated between different subfamilies. Synteny analysis indicates that there were 56 gene pairs in J. regia and A. thaliana, 76 in J. regia and J. mandshurica, 75 in J. regia and J. microcarpa, 76 in J. regia and P. trichocarpa, and 33 in J. regia and Q. robur, indicating that the WRKY gene family may come from a common ancestor. GO and KEGG enrichment analysis showed that the WRKY gene family was involved in resistance traits and the plant-pathogen interaction pathway. In anthracnose-resistant F26 fruits (AR) and anthracnose-susceptible F423 fruits (AS), transcriptome and qPCR analysis results showed that JrWRKY83, JrWRKY73 and JrWRKY74 were expressed significantly more highly in resistant cultivars, indicating that these three genes may be important contributors to stress resistance in walnut trees. Furthermore, we investigate how these three genes potentially target miRNAs and interact with proteins. JrWRKY73 was target by the miR156 family, including 12 miRNAs, this miRNA family targets WRKY genes to enhance plant defense. JrWRKY73 also interacted with the resistance gene AtMPK6, showing that it may play a crucial role in walnut defense.

Walnut is an important cultivated tree with high economic value and wide distribution across China. The objective was to breed a new walnut cultivar with high yield and desirable nut and tree qualities that could meet the demands of the walnut industry in China. ‘Liaoning 4’ walnut cultivar is lateral bearing which originated from a controlled cross between the Persian walnut (J. regia) selections ‘Liaoning Chaoyang big and rough walnut’ and ‘11001’. During long term assessment and research, ‘Liaoning 4’ walnut performed well and it was released as a new cultivar in China on 15 Oct. 2018. It has a high yield and excellent nut traits and has thus been widely planted in North China.

The Persian walnut (Juglans regia L.) is a leading source of woody oil in warm temperate regions and has high nutritional and medicinal values. It also provides both tree nuts and woody products. Nevertheless, incomplete characterization of the walnut genetic system limits the walnut gene function analysis. This study used the tobacco rattle virus (TRV) vector to construct an infectious pTRV-JrPDS recombinant clone. A co-culture inoculation method utilizing Agrobacterium was screened out from four inoculation methods and optimized to set up an efficient virus-induced gene silencing (VIGS) system for J. regia fruit. The optimized VIGS-TRV system induced complete photobleaching phenotype on the walnut fruits of four cultivars, and the JrPDS transcript levels decreased by up to 88% at 8 days post-inoculation (dpi). While those of browning-related J. regia polyphenol oxidase (PPO) genes JrPPO1 and JrPPO2 decreased by 67 and 80% at 8 dpi, respectively, accompanied by a significant reduction in fruit browning phenotype. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis screening and Western Blot showed that the PPO protein levels were significantly reduced. Moreover, a model of TRV-mediated VIGS system for inoculating J. regia fruit with efficient silence efficiency via co-culture was developed. These results indicate that the VIGS-TRV system is an efficient tool for rapid gene function analysis in J. regia fruits.

Simple Summary Agro-residues are usually discarded as landfill, or burnt or left to decompose in the orchard. The efficient use of these walnut agro-residues would be a strategy that simultaneously helps to preserve the environment and boosts the economic outcome for farmers and companies. While some studies have reported on the content of bioactive compounds in walnut husks, little or nothing is known to date about the bioactive compounds in the buds and bark. Potentially, if walnut parts are used as a valuable source of bioactive compound, they might still be reused for other purposes. The identification and quantification of new phenolics between the different parts of the plant was carried out. It provided valuable data on their phenolic contents, and demonstrated where the extraction of individual phenolics would be meaningful. These data also show origin-related phenolic contents across the cultivars, and thus these phenolic profiles might serve to define the origins of different walnut cultivars. The study will help to propose new directions for further studies essential for agro-food, cosmetics and pharmacy industries. Abstract The present study was designed to identify and quantify the major phenolic compounds (phenolics) in the inner and outer husks, buds and bark of the Persian walnut, Juglans regia L. A comparison across six different cultivars grown in Slovenia was also carried out: ‘Fernor’, ‘Fernette’, ‘Franquette’, ‘Sava’, ‘Krka’ and ‘Rubina’. A total of 83 compounds were identified, which included 25 naphthoquinones, 15 hydroxycinnamic acids, 8 hydroxybenzoic acids, 13 flavanols, 2 flavones, 1 flavanone and 19 flavonols. For the first time, 38 phenolics in the husks, 57 phenolics in the buds and 29 phenolics in the bark were presented in J. regia within this study. Naphthoquinones were the major phenolics determined, approximately 75% of all analysed phenolics in the inner husk, 85% in the outer husk, 50% in buds and 80% in bark. The highest content of phenolics was found in the walnut buds, followed by the bark, the inner husk and the outer husk. On the basis of these high phenolic contents, walnut husks, buds and bark represented valuable by-products of the walnut tree. These data also show origin-related phenolic contents across the cultivars, and thus these phenolic profiles might serve to define the origins of different walnut cultivars.

The food needs for increasing population, climatic changes, urbanization and industrialization, along with the destruction of forests, are the main challenges of modern life. Therefore, it is very important to evaluate plant genetic resources in order to cope with these problems. Therefore, in this study, a set of ninety-one walnut (Juglans regia L.) accessions from Central Anatolia region, composed of seventy-four accessions and eight commercial cultivars from Turkey, and nine international reference cultivars, was analyzed using 45 SSR (Simple Sequence Repeats) markers to reveal the genetic diversity. SSR analysis identified 390 alleles for 91 accessions. The number of alleles per locus ranged from 3 to 19 alleles with a mean value of 9 alleles per locus. Genetic dissimilarity coefficients ranged from 0.03 to 0.68. The highest number of alleles was obtained from CUJRA212 locus (Na = 19). The values of polymorphism information content (PIC) ranged from 0.42 (JRHR222528) to 0.86 (CUJRA212) with a mean PIC value of 0.68. Genetic distances were estimated according to the UPGMA (Unweighted Pair Group Method with Arithmetic Average), Principal Coordinates (PCoA), and the Structure-based clustering. The UPGMA and Structure clustering of the accessions depicted five major clusters supporting the PCoA results. The dendrogram revealed the similarities and dissimilarities among the accessions by identifying five major clusters. Based on this study, SSR analyses indicate that Yozgat province has an important genetic diversity pool and rich genetic variance of walnuts.

La bacteriosis del nogal es causada por Xanthomonas arboricola pv. juglandis. En Zavalla (Santa Fe), la actividad nogalera se centra en la producción de plantas injertadas en vivero. El presente trabajo tuvo por objetivo cuantificar el efecto ambiental sobre el desarrollo epidémico de la bacteriosis del nogal en variedades susceptibles y de mejor comportamiento a la enfermedad y elaborar modelos matemáticos que permitan predecir la severidad de la misma. En la localidad de Zavalla se realizaron observaciones de severidad (Sev%) de la bacteriosis cada siete días en cuatro variedades de nogal (tres susceptibles (sus=1): Chandler, Davis y Tulare y una de mejor comportamiento: Franquette (sus=0)), desde el fin de la primavera hasta los últimos días de febrero (N=76) durante tres campañas (2010/11, 2011/12 y 2012/13). Las variables regresoras meteorológicas se calcularon en los respectivos lapsos de 15 días previos a cada observación de tasa de incremento diario epidémico (Tid%=Sev%t–Sev%t-1/7). Las variables mejor correlacionadas (rk: coeficiente de correlación de Kendall Tau-b) con los niveles de bacteriosis (severo:Tid% >0,1367; moderado a nulo: Tid%9 (días con precipitación>9mm; rk=0,434) y DMojro (días sin lluvia, con mojado atribuible al rocío por ocurrencia de humedad relativa del aire mayor a 82%; rk=0,326). El modelo logístico integrado por DPr>9 y DMojro clasificó correctamente 62 casos de los 76 analizados en las tres campañas (precisión de predicción: PPred=81,5%), permitiendo cuantificar el efecto ambiental en ambos tipos de variedades de nogal analizadas. El modelo integrado por DPr>9 y DMojt (suma los días de mojado por rocío (DMojro) con los originados por precipitación (DMojpr)) logró una precisión de predicción de 80,3%. Ambas variables meteorológicas estarían expresando el requerimiento de agua libre de la bacteria para la infección (DMojt) y de energía en las lluvias (DPr>9) para favorecer la dispersión bacteriana. Walnut Blight is caused by Xanthomonas arboricola pv. juglandis. In Zavalla (Santa Fe), walnut production is focused on the grafted plants in nurseries. The objective of this work was to quantify the environmental effect on the epidemic development of walnut blight, in susceptible varieties and in varieties with better behaviour to the disease, and to develop mathematical models to predict the severity of the disease In the locality of Zavalla observations of severity (Sev%) of walnut blight were made every seven days in four walnut varieties (three susceptible (sus=1): Chandler, Davis and Tulare and one with better performance: Franquette (sus=0)), from the end of spring until the last days of February (N=76) , during three crop seasons (2010/11, 2011/12 and 2012/13). Weather regression variables were calculated in the respective 15-day periods prior to each observation of daily epidemic increase rate (Tid%=Sev%t-Sev%t-1/7). The variables best correlated (rk: Kendall Tau-b correlation coefficient) with bacterial levels (severe: Tid% >0.1367; moderate to nil) were Tid%9 (days with precipitation>9mm; rk=0.434) and DMojro (days without rain, with wetness attributable to dew due to the occurrence of relative air humidity greater than 82%; rk=0.326). The logistic model integrated by DPr>9 and DMojro correctly classified 62 cases of the 76 analyzed in the three crop seasons (prediction accuracy: PPred=81.5%), allowing to quantify the environmental effect in both types of walnut varieties analyzed. The model integrated by DPr>9 and DMojt (summing the days of wetting by dew (DMojro) with those originated by precipitation (DMojpr)) achieved a prediction accuracy of 80.3%. Both meteorological variables would be expressing the bacterial free water requirement for infection (DMojt) and energy requirement in rainfall (DPr>9) to provide bacterial dispersion. A bacteriose da nogueira é causada por Xanthomonas arboricola pv. juglandis. Em Zavalla (Santa Fe), o cultivo da nogueira concentra-se na produção de plantas enxertadas em viveiro. O objetivo deste trabalho foi quantificar o efeito do ambiente no desenvolvimento epidêmico da bacteriose da nogueira em variedades susceptíveis e de melhor comportamento e elaborar modelos matemáticos que permitam prever a sua severidade. En Zavalla foram feitas observações da severidade da bacteriose (Sev%) a cada sete dias em quatro variedades de nogueiras (três susceptíveis (sus=1): Chandler, Davis e Tulare e uma de melhor comportamento: Franquette (sus=0)), desde o final da primavera até os últimos dias de fevereiro (N=76), durante três safras (2010/11, 2011/12 e 2012/13),. As variáveis de regressão meteorológica foram calculadas nos respectivos intervalos de 15 dias antes de cada observação da taxa diária de progresso da epidemia (Tid%=Sev%t-Sev%t-1/7). As melhores variáveis correlacionadas (rk: coeficiente de correlação de Kendall Tau-b) com a severidade da bacteriose (severo:Tid% >0,1367; moderado a nulo: Tid%9 (dias com precipitação>9mm; rk=0,434) e DMojro (dias sem chuva, com molhamento devido ao orvalho pela ocorrência de umidade relativa do ar maior que 82%; rk=0,326). O modelo logístico integrado por DPr>9 e DMojro classificou corretamente 62 casos dos 76 analisados nas três safras (precisão de previsão: PPred=81,5%), permitindo quantificar o efeito do ambiente em ambos os tipos de variedades. O modelo integrado por DPr>9 e DMojt (soma dos dias com molhamento foliar pelo orvalho (DMojro) com os originados por precipitação pluvial (DMojpr)) atingiu uma precisão de previsão de 80,3%. Ambas as variáveis meteorológicas estariam expressando a necessidade de água livre para a infecção (DMojt) e o efeito mecânico da precipitação pluvial (DPr>9) na dispersão bacteriana. Com o uso do melhor modelo podem ser reduzidas as pulverizações com bactericida. Fil: Seta, Silvana Andrea. Universidad Nacional de Rosario, Facultad de Ciencias Agrarias, Santa Fe. Argentina Fil: Moschini, Ricardo Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Clima y Agua; Argentina Fil: González, Miriam del Pilar. Universidad Nacional de Rosario. Campo Experimental Villarino; Argentina.

Xanthomonas arboricola pv. juglandis’in neden olduğu ceviz yanıklık hastalığı, cevizin (Juglans regia L.) üretimini etkileyen en önemli ve yaygın bakteriyel hastalıklardan biridir. Hastalık etmeni ülkemiz ceviz üretim alanlarında ciddi ekonomik kayıplara neden olmaktadır. Tipik simptomlar sürgün, yaprak, dişi çiçek, tomurcuk ve meyve gibi tüm sulu dokularda görülür. Enfeksiyon başlangıçta su emmiş leke şeklindeyken zamanla bu lekeler kahverengi-siyah nekrotik alanlara dönüşür. Başlangıçta sarı-yeşil bir hale ile çevrelenmiş dairesel lezyonlar genellikle noktasal olarak genişler. Hastalık etmeni ile mücadelede kültürel önlemler ve bakırlı preparatlar önerilmektedir. Son yıllarda, bakteriyel hastalık etmenlerinin kontrolünde çevreye dost biyolojik mücadele üzerine çalışmalar artmıştır. Bu çalışmada; enfekteli bitkilerden Xanthomonas arbaricola pv. juglandis‘in izolasyonu ve tanılanması ve potansiyel aday bakteriyel antagonistlerin in vitro koşullarda bakteriyel büyümeyi baskılayabilme yetenekleri ve antagonistik potansiyelleri araştırılmıştır. Kütahya ili ceviz üretim alanlarına yapılan surveyler ile hastalıklı yaprak; sağlıklı yaprak ve çiçek örnekleri toplanmıştır. Hastalıklı yapraklardan patojen bakteri izolatı; sağlıklı çiçek ve yapraklarda antagonist bakteri izolatı elde edilmiştir. Bakteriyel hastalık etmeni izole edilmiş ve morfolojik ve biyokimyasal testlerle tanılanmıştır. Sağlıklı ceviz yapraklarından seçici besi ortamları kullanılarak izole edilen 109 adet aday antagonist bakteri izolatları ile in vitro koşullarda ikili kültür testi yapılarak Xanthomonas arbaricola pv. juglandis’i baskılama yetenekleri araştırılmıştır. Bu test sonucunda, 80 adet izolatın farklı boyutlarda (3.44-30.00 mm) engelleme alanı oluşturduğu, 37 adet izolatın ise gelişimini tamamen baskıladığı tespit edilmiştir. Yapılan çalışmada antagonist bakterilerin Xanthomonas arboricola pv. juglandis gelişimini önemli oranda engellemiş olması, antagonist izolatların biyolojik mücadelede kullanılabilirliğini göstermiştir. Hastalık etmenine karşı etkili bakteriyel izolatların tanılanması ve in vivo çalışmalarla etkinliğinin belirlenmesine yönelik çalışmalar yapılmalıdır., Walnut blight disease, caused by Xanthomonas arboricola pv. juglandis (Xaj), is one of the most important and common bacterial disease which effects production of walnut (Juglans regia L.) plants. The bacterial disease is led to economic losses significantly in juglans growth fields of Turkey. Typical symptoms occur on all succulent tissues including shoots, leaves, rachis, petioles, buds, female flowers, catkins and nuts. Infection begin as translucent water-soaked areas which develop into brown to blackish greasy necrotic areas. Lesions, which are often surrounded by a yellow-green halo, are initially circular but often expand into angular spots. Management of the pathogen is suggested the cultural methods and using copper compounds. Recently, controlling bacterial diseases the eco-friendly biological control studies are increased to control bacterial diseases. In this study, isolation and identification of disease agent Xaj from infected plants and antagonistic potentials of candidate bacterial antagonist biological control agent were investigated for their ability to suppress bacterial growth in vitro conditions. Bacterial disease agents were isolated and identified according to morphological and biochemical methods. Using selective nutrient media, total of 109 candidate antagonist bacterial isolates were isolated from different healthy walnut plant leaves and investigated for their ability to suppress bacterial growth in vitro conditions by dual culture test. From this test, eighty-one bacterial isolates were found to produce inhibition zones a varying size (range of 3.44-30.00 mm). Among the 80 isolates, thirty-seven isolates were able to suppress the bacterial growth completely. According to preliminary results of the significant suppression in the bacterial growth caused by antagonist bacteria, bacterial isolates could be used as possible biocontrol agent against walnut bacterial blight disease. Further studies should be conducted on identification and determination of mode of actions and in vivo activities of the most efficient bacterial isolates against disease agent.

The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as ‘High risk plants, plant products and other objects’. Taking into account the available scientific information, including the technical information provided by the applicant country, this Scientific Opinion covers the plant health risks posed by the following commodities: dormant, free of leaves grafted plants and rootstocks of Juglans regia imported from Moldova. A list of pests potentially associated with the commodities was compiled. The relevance of any pest was assessed based on evidence following defined criteria. None of the pests in the list fulfilled all relevant criteria and therefore none were selected for further evaluation. As a result, risk mitigation measures proposed in the technical dossier from Moldova were listed, but not further evaluated.

This study was designed to identify and quantify the major phenolic constituents in peeled kernel and pellicle of the walnut Juglans regia L. Data were compared across six different cultivars: 'Fernor', 'Fernette', 'Franquette', 'Sava', 'Krka' and 'Rubina'. High-performance liquid chromatography coupled with mass spectrometry was used to identify and quantify these compounds. Nineteen ellagitanins, 12 ellagic acid derivatives, 4 anthocyanins and 5 other phenols were identified in the pellicle of these walnuts, and 15 dicarboxylic acid derivatives and 1 phenol in the peeled walnut kernels. Thirteen previously unreported compounds were identified in the peeled walnut kernels, and 14 in the walnut pellicle. Hydrolysable tannins were the main phenolic compounds identified in the walnut kernels, and accounted for 31.0% to 35.1% of the total phenolics analysed. The highest intake of total phenolics content per walnut kernel can be obtained by consumption of 'Franquette' and 'Rubina', with the lowest for 'Krka'.

To counteract food fraud, this study aimed at the differentiation of walnuts on a global and regional level using an isotopolomics approach. Thus, the multi-elemental profiles of 237 walnut samples from ten countries and three years of harvest were analyzed with inductively coupled plasma mass spectrometry (ICP-MS), and the resulting element profiles were evaluated with chemometrics. Using support vector machine (SVM) for classification, validated by stratified nested cross validation, a prediction accuracy of 73% could be achieved. Leave-one-out cross validation was also applied for comparison and led to less satisfactory results because of the higher variations in sensitivity for distinct classes. Prediction was still possible using only elemental ratios instead of the absolute element concentrations, consequently, a drying step is not mandatory. In addition, the isotopolomics approach provided the classification of walnut samples on a regional level in France, Germany, and Italy, with accuracies of 91%, 77%, and 94%, respectively. The ratio of the model&rsquo, s accuracy to a random sample distribution was calculated, providing a new parameter with which to evaluate and compare the performance of classification models. The walnut cultivar and harvest year had no observable influence on the origin differentiation. Our results show the high potential of element profiling for the origin authentication of walnuts.

Key message NAC transcription factors may play important roles in the biological processes in Persian walnut. A total of 102 JrNACs were identified in Persian walnut. The conserved domains, transcriptome profile, expression analysis, and interaction network suggest that JrNAC1-4 plays potential roles in Persian walnut flowering development. Context: NACs are plant-specific transcription factors that participate in various plant developmental processes such as flowering, plant growth regulation, and development. We identified and analyzed the evolution and expression profiles of NAC genes in Juglans regia. Aims: The main objectives were to identify the NAC transcription factors and verify the expression levels in different tissues and female flowers in developmental stages in Persian walnut. Methods: We identified NAC transcription factors in J. regia based on the genome-wide analysis. We analyzed the phylogenetic relationships, conserved domain, chromosome location, gene structure, and gene collinearity of JrNACs. We also verified the JrNAC expression levels based on transcriptome analysis and qRT-PCR. Results: We identified 102 NAC genes in J. regia and divided them into ten subfamilies. A total of 30 pairs of JrNAC genes were expanded by whole genome duplications (WGDs) and one pair of genes (JrNAC 2-10 and JrNAC 9-8) as a tandem duplication in Persian walnut. Collinearity analysis results indicate that a large number of syntenic relationship events existed between J. regia and Populus trichocarpa. We found that JrNAC1-4 and JrNAC2-6 were expressed significantly higher in female flowers based on both transcriptome and qPCR analysis. We further identified that JrNAC2-9 and JrNAC9-6 were highly expressed at the end period of flowering stages. Conclusion: A total of 102 JrNACs were identified in the Persian walnut genome. These genes were conserved in plants for collinearity analysis, which was performed within the genome and other genomes (P. trichocarpa, Olea europaea, and Quercus robur). A total of 24 NAC transcription factors were highly expressed in female and male flowers, and these transcription factors play a role in J. regia flowering.

As the apparent incidence of tree nut allergies rises, the development of MS methods that accurately identify tree nuts in food is critical. However, analyses are limited by few available tree nut protein sequences. We assess the utility of translated genomic and transcriptomic data for library construction with Juglans regia, walnut, as a model. Extracted walnuts were subjected to nano-liquid chromatography–mass spectrometry (n-LC-MS/MS), and spectra were searched against databases made from a six-frame translation of the genome (6FT), a transcriptome, and three proteomes. Searches against proteomic databases yielded a variable number of peptides (1156–1275), and only ten additional unique peptides were identified in the 6FT database. Searches against a transcriptomic database yielded results similar to those of the National Center for Biotechnology Information (NCBI) proteome (1200 and 1275 peptides, respectively). Performance of the transcriptomic database was improved via the adjustment of RNA-Seq read processing methods, which increased the number of identified peptides which align to seed allergen proteins by ~20%. Together, these findings establish a path towards the construction of robust proxy protein databases for tree nut species and other non-model organisms.

Jammu and Kashmir region of India has a rich walnut germplasm that has arisen from populations of naturally grown seedlings and some introductions from other countries over many years. In this study, the genetic relatedness of 96 walnut genotypes adapted to the North Western Himalayan region of Jammu and Kashmir, India, was analyzed by 19 SSR markers. Genetic relationships among 96 walnut genotypes revealed very high polymorphism rate of 89.6%. Primer parameter values viz PIC, MI and Rp range from 0 to 0.43, 0 to 0.87 and 1.04 to 2.37 with an average of 0.168, 0.244 and 1.91 respectively. UPMGA dendrogram showed that all the accessions formed twelve main clusters with various degree of sub-clustering within the clusters. Model-based cluster analysis grouped 96 walnut genotypes into 5 genetically distinct sub-populations with varied level of admixture. Allele Frequency Divergence and expected heterozygosity vary from 0.00 to 0.057 and 0.043 to 0.067 with an average of 0.024 and 0.057 respectively between all the five populations. These studies will be helpful in association mapping studies for important traits in walnut. The high variability existing in the walnut germplasm suggested that it would be beneficial to utilize this germplasm pool in walnut breeding programs and germplasm management activities and also identified microsatellite markers for cultivar identification, characterization, registration and assessment in genebanks. Keywords: Juglans regia, SSR markers, Molecular characterization, Structure analysis, Genetic diversity

The morphological characteristics of female flowers and their parts in six walnut genotypes were described. The number of female flowers per inflorescence ranged from 1.9 to 2.7. The length and width of female flowers were 8.0–10.1 mm, and 3.4–3.8 mm, respectively. The average length and width of the ovule for all genotypes was 0.55 mm. The largest width of the ovule was 0.59 mm in the cultivar ‘Sheynovo’, and the smallest 0.51 mm in the cultivar ‘Geisenheim 139’. A significant positive correlation was found between the length and width of female flowers (r = 0.34⁎) and between the length and width of ovules (r = 0.57⁎⁎). Also, a significant negative correlations were found between the length of female flowers and the number of female flowers in the inflorescence (−0.58⁎⁎), and between the beginning of flowering and the duration of flowering (r = −0.66⁎⁎). The average width of the megaspore for all genotypes was 13.7 μm and of the mature embryo sac 70.2 μm. The average length of the mature embryo sac was 78.1 μm. The female flower morphogenesis occurred successively and in the same order in all examined genotypes. The differences by years and between genotypes referred to the time of onset and duration of the development stages. The characteristic phases of the female flower morphogenesis are described, and their dynamics are shown graphically for each genotype. The type of dichogamy had a significant influence on the rate of flower development. A high degree of concordance was found between the phases of female flower development and the stages of megasporogenesis and megagametogenesis. The paper presents photographs of comparative developmental stages that enable the assessment of the phases of megasporogenesis and megagametogenesis according to external morphological changes on female flowers and ovules.

The present study was designed to identify and quantify the major phenolic compounds in different Juglans regia L. (common walnut) tissues (leaves, petioles, bark, roots, buds), to define the compositions and contents of phenolic compounds between these tissues. A total of 91 individual phenolic compounds were identified and quantified, which comprised 8 hydroxycinnamic acids, 28 hydroxybenzoic acids, 11 flavanols, 20 flavonols, 22 napthoquinones, and 2 coumarins. Naphthoquinones were the major phenolic group in leaves, petioles, bark, and buds, as &gt, 60% of those identified, while hydroxybenzoic acids were the major phenolic group in side roots, as ~50% of those identified. The highest content of phenolic compounds was in the J. regia main root, followed by side roots and buds, leaves, and 1-year-old bark, the lowest content was in petioles and 2-year-old bark. Leaves, roots, and buds of J. regia represent a valuable source of these agro-residues.

The systematic killing of trees is usually aimed at eradicating pests or alien plant species susceptible to harm existing natural ecosystems. In some cases, trees may become the subject of dispute between neighbors, which sometimes ends in tree death after months or years of dispute. In this paper, we analyze a case of clandestine tree killing and look into ways through which evidence left by delinquents can be analyzed a posteriori with state-of-the-art approaches. The investigation presented here looks at a series of old-growth trees that were supposedly poisoned inside a protected, nineteenth century grove in Switzerland. After the sudden, unexplained death of several old Black poplar (Populus nigra) trees along the main alley in fall 2015 and their subsequent removal, the dying of five additional, neighboring Sycamore maple (Acer pseudoplatanus) and English walnut (Juglans regia) trees in 2016 promptly triggered a suite of criminal investigations at the property. During an initial inspection, a large number of boreholes was found in the root plates of the dying trees. We present findings obtained from tree-ring, wood anatomical and dendrogeochemical investigations performed on root, stem and leave material from the assumedly poisoned trees and show that massive amounts of chemical elements – supposedly in the form organic pesticides with high Al, As, Fe, Cr, Ni contents, aluminum phosphides or glyphosate-based pesticides – were injected into 36 boreholes drilled into the roots around September 2016. Results obtained in this study are currently used in criminal investigations, and are a nice example of how scientific detectives can help their “real World” colleagues in identifying delinquents., Dendroecology; Dendrogeochemistry; Tree wounding; Quantitative wood anatomy; Acer pseudoplatanus; Juglans regia; Applied ecology; Flora; Environmental assessment; Environmental health; Environmental toxicology; Environmental science.

A large number of human activities result in the release of potentially toxic elements (PTEs) into the environment, which could lead to the degradation of riparian areas. This study aimed to evaluate the potential of Salix alba, Juglans regia and Populus nigra for the biomonitoring of PTEs in the riparian soils of the Sava River. Levels of seven PTEs (As, Cd, Cr, Cu, Ni, Pb and Zn) were measured in the soils, roots and leaves of plants at selected sampling sites and evaluated according to bioaccumulation and translocation factors. The obtained results showed that in riparian soils, As, Cr, Cu, Ni and Zn were at levels considered to be critical for plants. The levels of As, Cd, Cr, Ni and Zn measured in roots of Salix alba and As, Cr, Ni and Zn in its leaves were toxic for plant tissue. Toxic levels of Cr were also measured in the roots of Juglans regia and As in its leaves, as well as As and Cr in the roots of Populus nigra, and Zn in its leaves. Bioconcentration and translocation factors showed that S. alba and P. nigra have potential for the phytoextraction of Zn and Cd, while J. regia has potential for the phytoextraction of As. In terms of phytostabilization potential, S. alba proved to be good for the phytostabilization of Cd and Cu, and J. regia for the phytostabilization of Cr, As, Ni and Pb, while P. nigra showed potential for the phytostabilization of Cr, Ni, Pb and Cu. This is a post-peer-review, pre-copyedit version of an article published in Environmental Monitoring and Assessment. The final authenticated version is available online at: [http://dx.doi.org/10.1007/s10661-020-8085-9]

International audience; Understanding the processes driving plant phenology is crucial for assessing how shifts in climate affect plant productivity and species’ distribution. Despite the key role of fine roots in carbon and nutrient cycling, root phenology is less well characterized than shoot phenology, due largely to methodological problems when measuring root systems at depths > 1.0 m. Fine root demography is also poorly related to the better established patterns of aboveground primary and secondary growth. We examined the influence of climatic factors on the dynamics of fine root elongation rate (RER), to a depth of 4.7 m, and assessed relationships with shoot phenology of walnut trees (Juglans nigra × J. regia) in a Mediterranean agroforestry system. Rhizotrons and minirhizotrons were installed for 21 months to monitor RER. Dendrometers were used to measure trunk and lateral root radial growth during the same period. Results showed that RER was not synchronous with budbreak and leaf unfolding (occurring from April to May) at any soil depth. However, during phase 2 of the growing season (June–November), daily RER in the upper soil (0.00–1.70 m) was synchronous with both trunk and lateral root radial growth, which were themselves positively correlated with the mean monthly soil and air temperatures and the mean monthly solar irradiance. Mean daily RER was not correlated to mean monthly soil and air temperatures at any soil depth during phase 2 of the growing season. However, during this period, mean daily RER of very shallow roots (0.00–0.85 m) was significantly and positively correlated with both mean monthly soil water content and solar irradiance. Maximal daily RER occurred during phase 2 of the growing season for the three upper soil layers (June–October), but peaked during the aerial dormant season (December) in the deepest soil layer (4.00–4.70 m). We conclude that drivers of phenology for different tree organs and between shallow and deep roots are not the same. This spatial plasticity in growth throughout a tree enables it to maximize resource uptake, even throughout the winter months, and thus is a highly useful mechanism for increasing tree resistance to abiotic stresses.

The common walnut (or Persian walnut), Juglans regia L., is an economically important temperate tree species valued for both its edible nut and high-quality wood. F-box gene family members are involved in plant development, which includes regulating plant development, reproduction, cellular protein degradation, response to biotic and abiotic stresses, and flowering. However, in common walnut (J. regia), there are no reports about the F-box gene family. Here, we report a genome-wide identification of J. regia F-box genes and analyze their phylogeny, duplication, microRNA, pathway, and transcriptional expression profile. In this study, 74 F-box genes were identified and clustered into three groups based on phylogenetic analysis and eight subfamilies based on special domains in common walnut. These common walnut F-box genes are distributed on 31 different pseudo-chromosomes. The gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and microRNA profiles showed that the F-box gene family might play a critical role in the flowering of common walnut. The expressions were significantly higher in female flowers and male flowers compared with leaf and hull tissues at a transcriptome level. The results revealed that the expressions of the F-box gene in female flowers were positively correlated with male flowers, but there was no correlation between any other tissue combinations in common walnut. Our results provided insight into the general characteristics of the F-box genes in common walnut.

This study compares the individual phenolic response of husk tissues of Juglans regia L., infected to different degrees of severity with walnut anthracnose, which is one of the most serious and widespread walnut diseases worldwide. A comparison among three differently susceptible cultivars, ‘Franquette’, ‘Milotai 10’ (‘M10’), and ‘Milotai intenziv’ (‘M10-37’), is made. In our methodology, high performance liquid chromatography coupled with mass spectrometry is used to identify and quantify the compounds. Our results show that flavanols, flavonols, and naphthoquinones account for more than 95% of the phenolic compounds identified in the walnut husk. The higher total analyzed phenolic content in tissues is more affected by walnut anthracnose confirmed that phenolics play a major role in the plant’s response against pathogens. A difference between cultivars is observed, since French cultivar ‘Franquette’ responds differently to walnut anthracnose infection than Hungarian cultivars ‘M10’ and ‘M10-37’. Naphthoquinones and flavanols have a very similar response to walnut anthracnose infection. The resistance of cultivars may be due to the reaction time of the plant and the speed with which it recognizes the pathogen and responds quickly to the infection by containing it while it has not yet spread. Flavonols may be the most important phenolic compounds in disease control, since they respond more rapidly to infection than flavanols and naphthoquinones. They also play an inhibitory role in the early stages of viral and bacterial infections.

The old walnut (Juglans regia L.) genotype called “Esterhazy II” was well-known in the Austro-Hungarian Monarchy before World War II, and it can still be found in the Austrian, German and Swiss backyard gardens today. Unfortunately, nowadays, vegetatively propagated progenies of the original “Esterhazy II” are not available anymore around the world because walnut grafting started later than this genotype had become well-known. Although various accessions with “Esterhazy II”-“blood“ are available, it is difficult to determine which one can be considered true or the most similar to the original one. In this paper, phenological and nut morphological characteristics of an “Esterhazy II” specimen planted in a Hungarian gene bank were compared to the varieties “Milotai 10” and “Chandler”. Examined characteristics were: budbreak, blossom time, type of dichogamy, ripening time, nut and kernel features. An additional SSR fingerprinting was used to identify identical genotypes and to demonstrate the relatedness of the analyzed “Esterhazy II” genotype to the other Hungarian walnut cultivars. It can be concluded that under the name “Esterhazy II”, several different genotypes can be observed. All the checked characteristics except budbreak fitted well with the previous descriptions. Our results confirmed that the examined “Esterhazy II” genotype shows high similarity to the “original“ “Esterhazy II” described in the literature.

Silver nanoparticles (AgNPs) have widespread applications. Recently, the synthesis of NPs using plant extract has attracted much attention. In this study, with an easy and rapid process at room temperature, AgNPs were produced by the aqueous extract of dried Juglans regia green husk, which is considered as a waste. The first sign of AgNPs synthesis was the color change of the sample from light green to yellowish brown. In addition, the production of AgNPs was examined by UV-Vis spectroscopy, dynamic light scattering (DLS), energy dispersive X-ray (EDX), Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis. The antibacterial effect of AgNP on Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus and anticoagulation activity were determined. Synthesized silver colloid had electromagnetic absorbance at approximately 450 nm. The hydrodynamic diameter of monodisperse AgNPs was approximately 67 nm. The face center cubic metallic silver, which was spherical in shape, was in the range 3–50 nm with the average size of 7 nm. The extract showed antioxidant activity against 1,1-diphenyl-2-picryl hydrazyl (DPPH). Phenolic compounds, tannins, flavonoids, reducing sugars, proteins, ascorbic acid and carotenoids existing in the extract acted as reducing agents. AgNPs may be capped by biomolecules having O-H, C=O, N-H and other stabilizing functional groups.

Data on the habitats of soldier-fly larva Beris heptapotamica Pleske, 1926 are reviewed for the first time. Morphological diagnostic characters differing the larva from those of other species from the genus Beris are discussed. Key to larvae of 7 palaearctic Beris species is given.

The natural dyes play a prominent role in maintaining the sustainability of any ecosystem due to their eco-friendly characteristics and relative non-toxicity over synthetic dyes. The aim of the present study was to investigate the possible dyeing capacity of the natural dye extracted from leaves of Juglans regia in association with mordant obtained from wood of Salix alba). The efficiency of the dye extraction was tested on wool, pashmina, cotton and silk by pre, instantaneous and post mordanting methods. The quality of the dye and the mordant observed to be the highest (28.88%) for pashmina and lowest for cotton (15.21%). Colour strength and coordinates exhibited the highest (0.886) for pashmina, followed by wool (0.761) and the lowest (0.718) for silk. Fastness grades of all the tested samples observed were mostly good to excellent. The dyed fabrics appeared with great light and dark brown with varying shades, efficacy and retention grades. However, cotton showed no affinity for the dye and mordant. The intermixing of natural dye with mordant in different mordanting methods illuminated their colour qualities with efficacy on tested fabrics. The study revealed that the dyeing ability of J. regia and mordant extracted from S. alba can be utilized commercially for industrial exploration.

Walnut (Juglans regia) is known as a promising woody oil crop with abundant polyunsaturated fatty acids in its kernel. However, the regulation mechanism of walnut oil accumulation and fatty acid metabolism is still poorly understood, which restricted the breeding and genetic improvement of high-quality oil-bearing walnuts. To reveal the molecular mechanism of walnut oil accumulation, considering the potential regulation of microRNA (miRNA) in seed development, in this study, the oil content of walnut kernel on the 80th, 100th and 120th day after flowering (DAF) was tested and the corresponding proportions are 11.51%, 40.40% and 53.20%. Between DAF of 80th~120th, the content of stearic acid and oleic acid tended to increase, but the proportion of other fatty acids tended to decrease. Meanwhile, comparative transcriptome and sRNA-seq analysis on three stages (80th, 100th and 120th DAF), found 204 conserved miRNAs and 554 novel miRNAs in walnut kernels, among which 104 key genes related to walnut oil accumulation were screened. The phospholipid:diacylglycerol acyltransferase metabolic pathway may contribute more to oil accumulation in walnut. 16 miRNA-mRNA regulatory modules related to walnut oil accumulation and fatty acid synthesis were constructed. 8 known miRNAs and 9 novel miRNAs regulate 28 genes involved in fatty acid (FA) metabolism and lipid synthesis. Among them, jre-miRn105, jre-miRn434, jre-miR477d and jre-miR156a.2 are key miRNAs that regulate walnut FA synthesis. Jre-miRn411 and jre-miR399a.1 are closely related to oil accumulation. These data provide new insights and lay the foundation for subsequent studies on walnut FA synthesis and oil accumulation.

Morphological characteristics of male reproductive organs (catkins, male flowers, anthers, and pollen) were studied in six walnut genotypes. Morphology and ultrastructure of pollen grains were studied using scanning electron microscopy (SEM) technique. Numbers of catkins per shoot and node ranged 2.35–5.61, and 0.29–0.73, respectively. They were higher in protandrous genotypes, compared with protogynous ones. The average values for catkin characteristics for all genotypes were: length 120 mm, width 15 mm, and the number of male flowers in catkin 120. Catkin length was higher in genotypes with the later time of pollen shedding. The average number of stamens in a male flower for all genotypes was 19, while average anther dimensions were: length 2.32 mm, width 0.96 mm, and thickness 0.75 mm. Significant differences between genotypes were found for all catkin and anther characteristics, except for catkin width. Pollen grains of all examined walnut genotypes were isopolar and pantoporate. They are classified as medium-large in size, with the average length of the polar axis (P) 36.84–39.88 μm, and the average length of the equatorial axis (E) 43.12–46.37 μm. The average P/E ratio varied between 0.85 and 0.88 and, based on this, pollen shape was identified as suboblate. All studied genotypes had microechinate exine ornamentation. The number of microechini per an area of 100 μm−2 of the exine surface varied between 22 and 25. Results obtained by SEM examination indicated that some pollen characteristics, such as size, shape, and microechini density can potentially be used in the identification of walnut genotypes.

Walnut (Juglans regia L.) is one of the most important nut tree species. Simple sequence repeat (SSR)-based genetic linkage maps are valuable and effective tools for studies on integrative and comparative mapping. The data available in literature on walnut is inadequate for linkage mapping. Therefore, in the present study, we aimed to construct the first SSR-based genetic linkage map using the ‘Chandler’ × ‘Kaplan-86’ F1 population and to identify QTL (Quantitative Trait Loci) for leafing time in walnut. A total of 386 SSRs were mapped to 16 linkage groups (LGs) after screening 1437 SSR primer pairs. Among the mapped markers, 166 SSRs (43.0%) were heterozygous in both the parents, whereas 113 (29.3%) and 107 (27.7%) markers were from one of the parents that were integrated into the female and male maps, respectively. The total length of the consensus map was 1568.2 cM, with an average length of 98.0 cM. It included an average of 24.1 markers per LG, and the mean distance between SSR markers was 4.3 cM. The Chandler maternal linkage map included 279 SSR markers of total map length 1285.8 cM, whereas the Kaplan-86 male genetic map contained 273 SSRs of total map length 1574.4 cM. The SSR-based linkage maps presented in this study are moderately dense and can be considered as a fundamental genetic linkage map for further genetic and molecular studies in walnut, as well as in other Juglans species. A major QTL was identified for leafing time on LG4 explaining 52.0–68.8% of the phenotypic variation at similar positions in parental and consensus maps. The identified QTL region with associate markers can be potential for marker-assisted selection in the future for walnut breeding programs. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.

Çanakkale ili Çan ilçesinin atmosferik yapısı, termik santral, kış aylarında ısınma amaçlı yakılan linyit kömürü ve diğer endüstriyel faaliyetler nedeniyle başta kükürtdioksit olmak üzere çeşitli kirletici baca gazlarının zararlı etkileri altındadır. Kükürt kararlı izotop analizi, kükürt kaynaklarını ayırt etmek için son zamanlarda kullanılmaktadır. Bu çalışmada termik santral çevresindeki Juglans regia L. taksonu yapraklarındaki kükürt kararlı izotop miktarı değişimi ile yapraklarındaki bazı anatomik özelliklerinin ortaya konulması amaçlanmıştır. 18 Mart Çan Termik santrali merkezde kalacak şekilde 3x3km2'lik 49 grid oluşturulmuştur. Her bir grid içerisinde bulunan Juglans regia taksonundan örnekler alınarak kararlı kükürt izotop analizi yaptırılmıştır. Doğu-Batı ve Güney-Kuzey yönleri üzerinden 2 eksen geçirilmiş ve 4 bölge belirlenmiştir. Bölgeler Kuzey ile Batı yönleri arasında kalan bölgeden başlanılarak, saat yönünde 1'den 4'e kadar numaralandırılmıştır. Bazı gridler seçilerek stoma yoğunluğuna ve stoma ölçümüne bakılmış ve kükürt kararlı izotop analizi sonuçlarının kontrolü yapılmıştır. Termik santral bacasını merkeze alan düzlemde hakim rüzgar olan Kuzeyli rüzgarlarının en çok estiği Güneybatı yönündeki (3. bölgede) gridler içerisinde yer alan örneklerin δ34S oranında ortalama ‰ -1.46 ± 3.15 ile bir düşme, diğer yönlerdekilerde ise zenginleşme görülmüştür. δ34S oranındaki en fazla zenginleşmenin de ‰ +2.36 ± 1.38 ile 1. bölge olduğu belirlenmiştir. Benzer şekilde kükürt kompozisyonu bakımından 3. ve 4. bölgelerdeki örneklerin kükürt yüzdesinin, 1. ve 2. bölgelerden toplanan örneklere göre istatistiksel olarak daha zengin olduğu belirlenmiştir (p

Natural tannins from various plants have been used throughout human history in textile dyeing, often as mordant dyes. The ageing behavior of these dyes is a challenge in conservation science, requiring a thorough knowledge of the textile&ndash, mordant-dye system. In this work, we analyzed reference wool yarns dyed with natural tannins from oak gallnuts, walnut (Juglans regia), and catechu (Acacia catechu), after artificial ageing. To gain insights on the composition of the dyestuffs and on how they aged, an analytical procedure based on extraction with Na2EDTA/DMF (ethylenediaminetetraacetic acid/dimethylformamide) and high-performance liquid chromatography (HPLC) analysis using high-resolution mass spectrometry detection was used. Since conventional reversed-phase (RP) columns usually show poor retention efficiency of highly polar compounds such as tannins, an RP-amide embedded polar group stationary phase was used to achieve optimal retention of the most polar compounds. Tannins from oak gallnuts showed little degradation after ageing, while a significant increase in the content of hydroxybenzoic acids was observed for tannins from walnut and catechu. Finally, the analytical procedure was applied to characterize the tannin dyes in historical tapestries from the 15th to 16th century, and the results were discussed in comparison with the reference yarns.

The common walnut (Juglans regia L.) and iron walnut (J. sigillata Dode) are well-known economically important species cultivated for their edible nuts, high-quality wood, and medicinal properties and display a sympatric distribution in southwestern China. However, detailed research on the genetic diversity and introgression of these two closely related walnut species, especially in southwestern China, are lacking. In this study, we analyzed a total of 506 individuals from 28 populations of J. regia and J. sigillata using 25 EST-SSR markers to determine if their gene introgression was related to sympatric distribution. In addition, we compared the genetic diversity estimates between them. Our results indicated that all J. regia populations possess slightly higher genetic diversity than J. sigillata populations. The Geostatistical IDW technique (HO, PPL, NA and PrA) revealed that northern Yunnan and Guizhou provinces had high genetic diversity for J. regia while the northwestern Yunnan province had high genetic diversity for J. sigillata. AMOVA analysis revealed that significant genetic variation was mainly distributed within population as 73% in J. regia and 76% in J. sigillata. The genetic differentiation (FST) was 0.307 between the two walnut species (p &lt, 0.0001), which was higher than FST values within populations (J. regia FST = 0.265 and J. sigillata FST = 0.236). However, the STRUCTURE analysis of the J. regia and J. sigillata populations revealed two genetic clusters in which gene introgression exists, therefore, the boundary of separation between these two walnut species is not clear. Moreover, these results were validated by NJ and UPGMA analysis with additional conformation from the PCoA. Based on the SSR data, our results indicate that J. sigillata is an ecotype of J. regia. Taken together, these results reveal novel information on population genetics and provide specific geographical regions containing high genetic diversity of the Juglans species sampled, which will assist in future conservation management.

Common walnut (Juglans regia L.) is an economically important hardwood tree species cultivated worldwide for its high quality wood and edible nuts. It is generally accepted that after the last glaciation J. regia survived and grew in almost completely isolated stands in Asia, and that ancient humans dispersed walnuts across Asia and into new habitats via trade and cultural expansion. The history of common walnut in China is a matter of debate, however. We estimated the genetic diversity and spatial genetic structure of 31 walnut populations sampled across its Chinese range using 22 microsatellite markers (13 neutral and 9 non-neutral). Using historical data and population genetic analysis, including approximate Bayesian analysis (ABC), we reconstructed the demographic history of J. regia in China. The genetic data indicated the likely presence of J. regia in glacial refugia in the Xinjiang province (Northwest China), Northeastern China (Beijing, Shandong, and Changbai Mountains), Central China (Qinling and Baishan Mountains and Xi’an), and Southwestern China (Tibet, Yunnan, Guizhou, and Sichuan provinces). Based on DIY-ABC analysis, we identified three ancient lineages of J. regia in China. Two lineages (subpopulation A and subpopulation B+C) diverged about 2.79 Mya, while Southwestern China, and Qinling and Baishan Mountains lineages diverged during the Quaternary glaciations (about 1.13 Mya). Remnants of these once-distinct genetic clusters of J. regia may warrant ecological management if they are to be retained as in situ resources. A population size expansion in Northeastern China was detected in the last five centuries. The present distribution of walnut in China resulted from the combined effects of expansion/contraction from multiple refugia after the Last Glacial Maximum and later human exploitation.

Agroforestry Systems, 87 (1), ISSN:0167-4366, ISSN:1572-9680

Fruit of walnut (Juglans regia L.) belongs to stone fruits. This means that the lignified, stony endocarp, a shell, contains delicious kernel. On the tree a nut is surrounded by the green husk.In Slovenia and in the other parts of the world heavy tools (such as stone, hammer and hand-crusher for nuts) are used to remove nutshell. In the intensive walnut production heavy tools are not competitive with today world economy. This is because the priority in walnuts and nuts kernel production is to reduce costs. Walnut shell cracking devices are invented to reduce walnut handling costs and consumer price. Characteristics of this device and walnut kernel quality are presented in this research.

Walnut trees have been shown to be very sensitive to abiotic stresses, especially to soil hy-poxia consequence of soil flooding or waterlogging. The aim of study was to search for cor-relation between polyphenols and tolerance to flooding stress. Two-three years old walnut trees, Juglans regia, J. nigra and interspecific hybrids, grown in pots were subjected to soil flooding in summer at full leaves expansion. In high sensitive J. regia trees, when flooded, the net CO2 assimilation rapidly decreased and 3-4 days of flooding were enough to block the recovery when soils was drained. In walnut hybrid (J. nigra x J. regia) and less sensitive J. regia genotypes, a longer resistance was observed; after 13 days of treatment leaves could still be green and trees can recovered till to the normal photosynthesis when drained. J. nigra when flooded reduced net photosynthetic rate but maintained leaves without dam-ages and with the capacity to recover CO2 assimilation. The data showed resistance of J. nigra and hybrid trees and of some J. regia genotypes to the stress. The HPLC analyses of polyphenols showed a modification of the patterns during the stress. The plants less tolerant to hypoxia have higher content of polyphenols distributed in a lot of compounds. Trees more tolerant, J. nigra, showed a very simple HPLC pattern. All samples contained juglone, more in less tolerant genotypes. Hydroxy juglone glucoside was detectable in all genotypes, but only in low quantity, it increased in trees with high resistance to hypoxia and decreased in J. regia. Less flooded tolerant J. regia genotypes have higher polyphenols and juglone content. The metabolism of hydroxy ljuglone glucoside could be involved in a mechanism of juglone detoxification during the hypoxia to give stress tolerance.

Cultivation of woody oil plants in environmentally suitable habitats is a successful ecological solution for oil development and forest management. In this study, we predicted the influences of future climate change on the potentially suitable climatic distribution of an important woody oil plant species (walnut; Juglans regia L.) in China based on given climate change scenarios and the maximum entropy (MaxEnt) model. The MaxEnt model showed that the minimum temperature of the coldest month and annual precipitation were the most important determinant variables limiting the geographical distribution of J. regia. We have found that the current suitable environmental habitat of J. regia is mainly distributed in central and southwestern China. Results of the MaxEnt model showed that global warming in the coming half-century may lead to an increase in the area size of environmentally suitable habitats for J. regia in China, indicating more lands available for artificial cultivation and oil production. However, those suitable habitat gains may be practically inaccessible due to over-harvest and urban development, and effective management strategies are urgently needed to establish those forests. This research will provide theoretical suggestions for the protection, cultivation management, and sustainable utilization of J. regia resources to face the challenge of global climate change.

UMR 1332 - Equipe A3C; International audience; Persian or English walnut (Juglans regia L.), the walnut species cultivated for nut production, is one of the oldest food sources known and is grown worldwide in temperate areas. France is the 7th leading producer as of 2016 with 39 kt. Deciphering walnut genetic diversity and structure is important for efficient management and use of genetic resources. In this work, 253 worldwide accessions from the INRA walnut germplasm collection, containing English walnut and several related species, were genotyped using 13 SSR (Single Sequence Repeat) markers selected from the literature to assess diversity and structure. Genetic diversity parameters showed a deficiency of heterozygotes and, for several SSRs, allele-specificities among the accessions tested. Principal Coordinate Analysis (PCoA) showed the 253 accessions clustered in largely in agreement with the existing botanical classification of the genus. Among the 217 J. regia accessions, two main clusters, accessions from Eastern Europe and Asia, and accessions from Western Europe and America, were identified using STRUCTURE software. This was confirmed by Principal Coordinate Analysis and supported by Neighbor-Joining tree construction using DARwin software. Moreover, a substructure was found within the two clusters, mainly according to geographical origin. A core collection containing 50 accessions was selected using the maximum length sub-tree method and prior knowledge about their phenotype. The present study constitutes a preliminary population genetics overview of INRA walnut genetic resources collection using SSR markers. The resulting estimations of genetic diversity and structure are useful for germplasm management and for future walnut breeding programs.

Even if cancer represents a burden for human society, an exhaustive cure has not been discovered yet. Low therapeutic index and resistance to pharmacotherapy are two of the major limits of antitumour treatments. Natural products represent an excellent library of bioactive molecules. Thus, tapping into the natural world may prove useful in identifying new therapeutic options with favourable pharmaco-toxicological profiles. Juglans regia, or common walnut, is a very resilient tree that has inhabited our planet for thousands of years. Many studies correlate walnut consumption to beneficial effects towards several chronic diseases, such as cancer, mainly due to the bioactive molecules stored in different parts of the plant. Among others, polyphenols, quinones, proteins, and essential fatty acids contribute to its pharmacologic activity. The present review aims to offer a comprehensive perspective about the antitumour potential of the most promising compounds stored in this plant, such as juglanin, juglone, and the ellagitannin-metabolites urolithins or deriving from walnut dietary intake. All molecules and a chronic intake of the fruit provide tangible anticancer effects. However, the scarcity of studies on humans does not allow results to be conclusive.

To better understand carbon (C) sequestration by Juglans regia L. plantations in karst regions of southwest China, this study examined biomass increment and C storage in four different-aged J. regia stands, as well as the distribution of carbon stock among the various ecosystem components. Tree and ecosystem biomass increased with stand age. Aboveground biomass (AGB) represented 64.79% of the total biomass, belowground tree biomass comprised 22.73%, and shrubs and herbs totaled 11.38%, whereas only a small amount (1.11%) was associated with soil litter. Soil organic C (SOC) content in the top soil of plantations aged 1, 5, 9, and 13 years was 33.37, 53.15, 33.56, and 49.78 mg ha−1, respectively. SOC content decreased continually with increasing soil depth. Ecosystem C storage amounted to 33.49, 54.21, 46.40, and 65.34 mg ha−1 for the 1-, 5-, 9-, and 13-year old plantations, respectively, with most (86.55%) of the ecosystem C being in the soil. Our results suggest that large-scale planting of J. regia has potential for not only vegetation restoration but also high C fixation capacity in the karst region of southwest China.

A series of novel naphthoquinone amide derivatives of the bioactive quinones, plumbagin, juglone, menadione and lawsone, with various amino acids were synthesized. The compounds were characterized by 1H NMR, 13C NMR, Mass, IR and elemental analysis. All the compounds were evaluated for their anticancer activity against HeLa and SAS cancer cell lines and 3D-QSAR indicated the presence of electron donating group near sulphur enhanced the activity against HeLa cells. Among the derivatives synthesized, compounds 11f, 10a, 10b and 10g were the most active with IC50 values of 16, 12, 14 and 24.5 ?M, respectively. The analogues were also screened for antimicrobial activity against two human bacterial pathogens, the Gram-positive Methicillin resistant Staphylococcus aureus (MRSA) and the Gram-negative Pseudomonas aeruginosa and a human yeast pathogen, Fluconazole resistant Candida albicans (FRCA). Among the synthesized compounds, 8g, 10g and 11g exhibited maximum antibacterial activity towards MRSA and antifungal activity against FRCA in well diffusion method. � 2014 Elsevier Ltd. All rights reserved.

The aim of this study was to determine the level of heavy metals such as copper, iron, manganese, zinc, lead, nickel, cadmium and chromium concentrated in Juglans regia bark and leaf samples from different localities in Artvin, Turkey. Analysis of the heavy metals Cu, Fe, Mn, Zn, Pb, Ni, Cd and Cr in samples was carried out by inductively coupled plasma optical emission spectroscopy (ICP-OES; Perkin Elmer, Optima 8000 DV). Statistical significance was determined by analysis of variance (ANOVA). The comparisons were performed in order to determine whether there were any differences between J. regia bark and leaf samples in terms of average heavy metal accumulation levels. As a result of this study, the following mean concentrations were determined for J. regia bark samples: the contents of Cu, Fe, Mn, Zn, Pb, Ni, Cd and Cr (μg g-1, dry weight) ranged from 72.46 to 88.14, 14.40 to 628.0, 0.896 to 67.71, 7.000 to 28.52, 0.040 to 0.905, 1.031 to 2.744, 0.011 to 0.158 and 1.192 to 3.134, respectively. On the other hand, for J. regia leaf samples, the contents of Cu, Fe, Mn, Zn, Pb, Ni, Cd and Cr (μg g-1, dry weight) ranged from 0.339 to 13.80, 12.72 to 698.2, 1.001 to 204.6, 7.362 to 56.03, 0.158 to 0.665, 0.130 to 2.744, 0.041 to 0.114 and 0.508 to 2.767, respectively. In the statistical analysis, heavy metal accumulation values of J. regia bark and leaf samples for Cu, Ni and Cr were significantly different (P < 0.05). © 2014, Diagnosis Press Limited. All rights Reserved.

Persian walnut (Juglans regia L) is an economically important species cultivated worldwide for its wood and nuts. Despite the increasing interest in the development of conservation strategies for walnut germplasm, an accurate and full-scale overview of wild genetic resources of J. regia has not been conducted because natural populations are located in regions of Asia historically difficult to access. In this study, we estimated the genetic diversity and spatial genetic structure of 39 autochthonous Persian walnut populations sampled across its Asian range using 14 neutral microsatellite markers. A landscape genetic overlay approach was applied to detect the areas of current reservoirs of walnut genetic diversity in the Asian range and to evaluate the role of landscape in shaping walnut genetic diversity since the Last Glacial Maximum. Although Persian walnut has been highly manipulated by humans over the last 2,000 years, we determined that patches of high genetic diversity still exist in the Caucasus and mountains of Central Asia where J. regia might have survived after Pleistocene glaciations. We detected a clear separation of Persian walnut into four main genetic clusters centered in (1) western Kyrgyzstan, (2) western and south-central Asia, (3) east-central Uzbekistan, and (4) Xinjiang and Shandong provinces (China). Overlay of maps showed a coincidence between groups of walnut populations and potential barriers to gene flow such as the Hindu Kush, Pamir, Tien Shan, and Himalaya mountains and the Karakum, Kyzyl Kum, and Taklamakan deserts. This study claimed the relevance of the preservation of walnut genetic resources in the Asian range.

The Central Asia where walnut grown since Oligocene was recognized as a center of its origin and distribution. Now in Uzbekistan, J. regia stands occupy three areas geographically isolated each other by more than 250 km: Western Tien-Shan, Nurata and Hissar. Survey expeditions were performed mainly in natural thickets, half-wild plantations and single tree in "dehkan" gardens. Morphological descriptors, biochemical and genetic markers were used to evaluate the biodiversity of walnut for conservation and developmental use. Trees from 20-30 years up to over-matured (300-500 years old) were considered. A variety in nuts was recorded: as to weight (5 up to 25 g) and other morphological and biochemical attributes. Lipid in kernels contain PUFA for more of 80%. Vitamin E was also extracted in the range 0.1-1.5 mg/g of kernel. Using 14 SSR primers, DNA fragments of different size were obtained with variable number of alleles in the walnut trees sampled. Spatial genetic structure analysis divided the Uzbek trees into three groups that partially corresponded to the growing area of trees. Studies in progress preliminary indicated that the genetic structure of Uzbek walnut partially overlapped to trees from outside the country. The ancestors of Uzbek trees could share the origin with the nearby forests, now belonging to other Countries, but in the past together identified as Turkestan, and focal point of the Silk Roads for East-West trade and migrations.

Rejuvenation is an efficient approach used in the cuttings of trees and horticultural crops, to improve their rooting ability, especially in difficult-to-root trees. WOX gene family members are involved in cell-fate transformation through balancing the maintenance and proliferation of the stem cells. However, there are no reports about the WOX gene family in Walnut (Juglans regia L.) and its relationship between rejuvenation and adventitious roots formation (ARF). Here, a genome-wide identification of JrWOX genes and their physical and chemical properties, phylogeny, and expression profiles in different organs and during rejuvenation-induced ARF is reported. The phenotype and histology characteristics of mature and rejuvenated cuttings (Mc and Rc) are also observed. In this study, 12 genes were identified and clustered into three groups based on phylogenetics, special domains, and conserved motifs. The gene structures and conserved motifs were relatively conserved, while the 12 sequences of the JrWOXs domain were diversified. Gene expression in root, stem, leaf, female flower, immature fruit, and zygotic embryo revealed that the expression levels of JrWOX4a, JrWOX4b, JrWOX5, JrWOX11, and JrWOX13 in the root were significantly higher than those of other JrWOXs, while only the expression of JrWOX11 was exclusive to the root organ. Additionally, rejuvenation treatment significantly induced almost all JrWOX genes, except JrWOX4a, JrWOX4b, and JrWOX13 (Rc 0 vs. Mc 0). During the ARF process, the transcripts of JrWOX11 and JrWOX5 were consecutively increased on a significance level, in contrast, the transcription levels of the other JrWOXs decreased or changed insignificantly. The phenotype and histology observation indicate that rejuvenation treatment made the base of the stem expand and reduced the thickness and density of sclerenchyma between the cortex and phloem. This might provide the conditions for the formation of new meristem niches. The results provided insight into the JrWOX genes&rsquo, general characteristics and their roles in rejuvenation-induced ARF.