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Common walnut (Juglans regia L.) is a valuable nut crop widely distributed within the temperate climate zone. It has several secondary centers of origin associated with refugia formed during the LGM (Last Glacial Maximum) period, one of which was presumably located in the Caucasus region. Currently, walnut populations of the Caucasus are studied fragmentarily, especially in the northeast. Our study is aimed at investigating the genetic diversity, population structure, and possible walnut introduction processes in the Caspian region of the Northeast Caucasus (Dagestan). Genotyping using 11 SSR markers was performed for 158 samples from local walnut populations. Also, to identify the introduction facts, 42 varieties of different geographical origin were added to research. The SSR markers genetic diversity in the analysis of population varied from four to 20 alleles per locus, with an average value of 9.82. Analysis of the genetic structure revealed significant genetic differences between the subpopulations of the Mountain and Flatland Dagestan. Presumably, the structure of the gene pool could have been influenced by terrain factors and ethnocultural characteristics. Subpopulations of Flatland Dagestan have an intermediate position between the western cultivars and the gene pool of Mountain Dagestan, which subpopulations showed significant genetic isolation. In the studied samples set of population selections, the established introduction facts were rare. We have suggested that a significant part of the walnut gene pool from Mountain Dagestan has an autochthonous origin from plants that survived the LGM in the Caucasian refugia. Our results are the basis for further studies of the local gene pool and verification of hypothesis about the presence of an indigenous germplasm preserved in this region from the LGM period. [ABSTRACT FROM AUTHOR]

Trees are exposed to significant spatio-temporal thermal variations, which can induce intra-crown discrepancies in the onset and dynamics of primary and secondary growth. In recent decades, an increase in late winter and early spring temperatures has been observed, potentially accelerating bud break, cambial activation, and their coordination. Intra-crown temperature heterogeneities could lead to asymmetric tree shapes unless there is a compensatory mechanism at the crown level. An original warming experiment was conducted on young Juglans regia trees in a greenhouse. The average temperature difference during the day between warmed and control parts from February to August was 4 °C. The warming treatment advanced the date of budbreak significantly, by up to 14 d. Warming did not alter secondary growth resumption but increased growth rates, leading to higher xylem cell production (by 2-fold) and to an increase in radial increment (+80% compared with control). Meristem resumptions were asynchronous without coordination in response to temperature. Buds on warmed branches began to swell 2 weeks prior to cambial division, which was 1 week earlier than on control branches. A difference in carbon and water remobilization at the end of bud ecodormancy was noted under warming. Overall, our results argue for a lack of compensatory mechanisms at the crown scale, which may lead to significant changes in tree architecture in response to intra-crown temperature heterogeneities. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia L.) is a widely grown nut plant worldwide, including in Guizhou Province, located in southwest China. The high quality and special taste make Guizhou walnuts, particularly those produced in Hezhang County, a "Chinese National Geographical Indication Product" that substantially contributes to the local economy and grower's income. In July 2022, a serious occurrence of leaf spot disease was observed in a walnut plantation area, Shuitang Town, Hezhang County, Guizhou Province, China (27°07'67"N, 104°64'61"E). The causal agent was identified as Didymella segeticola through morphological characterization and amplification and sequencing of the internal transcribed spacer (ITS) region, beta-tubulin (TUB) gene, and glyceraldehyde-3-phosphate dehydrogenase (G3PD) gene. Koch's postulates, including re-isolation and identification, were performed to confirm its pathogenicity on healthy leaves. To our knowledge, this is the first report of D. segeticola causing leaf spot on walnuts worldwide. Further, to determine its biological characteristics, which could be utilized for future disease management, the effects of temperature, light, and carbon and nitrogen resources on mycelial growth, conidia production, and conidia germination and the effects of humidity on conidia germination were studied. The optimum temperature for mycelial growth of representative strain D. segeticola C27 was 20°C. Increasing the light period significantly decreased conidia production and conidia germination. Maltose and beef extract were the best carbon and nitrogen sources, respectively, for the pathogen. Conidia germination was enhanced at 90% humidity. In vitro screening of effective fungicides was conducted. Among the 20 screened fungicides, difenoconazole showed the best inhibition rate, with an EC50 (concentration for 50% of the maximal effect) of 0.0007 µg/mL. Tetramycin also showed sufficient inhibitory effects against D. segeticola, with an EC50 value of 0.0009 µg/mL. Our study provides new insights into the causal agent of walnut leaf spot in Guizhou, China, as well as the first pathogen characteristics and promising candidate fungicides for its management. [ABSTRACT FROM AUTHOR]

This review aims to provide a detailed overview of the botanical, phytochemical, and dermatological properties of Juglans regia (J. regia). The entire tree contains a wealth of chemical compounds, including phenols, tannins, alkaloids, saponins, reducing sugars, and amino acids, which contribute to its significant nutritional and pharmacological value. Extracts and oils from all parts of J. regia have been studied for their effects on various skin conditions, demonstrating antioxidant, antimicrobial, anti-inflammatory, UV-protective, and chemoprotective properties. Additionally, these substances have shown potential in promoting wound healing, anti-aging, skin hydration, anti-tyrosinase activity, and hair dyeing. These benefits have been evaluated in various in vitro and in vivo studies. The therapeutic potential of J. regia suggests that its components could be integrated into treatment protocols and skincare routines. However, to optimize effectiveness and safety, future research should focus on in vivo studies in human subjects to determine the ideal concentrations and formulations of J. regia active compounds for specific skin conditions. [ABSTRACT FROM AUTHOR]

Background: The Persian walnut (Juglans regia), an economically vital species within the Juglandaceae family, has seen its mitochondrial genome sequenced and assembled in the current study using advanced Illumina and Nanopore sequencing technology. Results: The 1,007,576 bp mitogenome of J. regia consisted of three circular chromosomes with a 44.52% GC content encoding 39 PCGs, 47 tRNA, and five rRNA genes. Extensive repetitive sequences, including 320 SSRs, 512 interspersed, and 83 tandem repeats, were identified, contributing to genomic complexity. The protein-coding sequences (PCGs) favored A/T-ending codons, and the codon usage bias was primarily shaped by selective pressure. Intracellular gene transfer occurred among the mitogenome, chloroplast, and nuclear genomes. Comparative genomic analysis unveiled abundant structure and sequence variation among J. regia and related species. The results of selective pressure analysis indicated that most PCGs underwent purifying selection, whereas the atp4 and ccmB genes had experienced positive selection between many species pairs. In addition, the phylogenetic examination, grounded in mitochondrial genome data, precisely delineated the evolutionary and taxonomic relationships of J. regia and its relatives. We identified a total of 539 RNA editing sites, among which 288 were corroborated by transcriptome sequencing data. Furthermore, expression profiling under temperature stress highlighted the complex regulation pattern of 28 differently expressed PCGs, wherein NADH dehydrogenase and ATP synthase genes might be critical in the mitochondria response to cold stress. Conclusions: Our results provided valuable molecular resources for understanding the genetic characteristics of J. regia and offered novel perspectives for population genetics and evolutionary studies in Juglans and related woody species. [ABSTRACT FROM AUTHOR]

Caloptilia roscipennella (Hübner, 1796) is a leaf‐mining moth native to Central and Southern Europe. In this publication, we provide the first report of the occurrence of Caloptilia roscipennella in India. The identification was performed using an integrative approach, combining molecular (barcoding, COI) and morphological analysis (forewing pattern). In 2020, the larvae were initially found scraping in the silvery‐white mine and later feeding in folded or rolled leaves of the common walnut Juglans regia L. In the subsequent years, the species was found only in the same places. Two generations were recorded per year (May–June and August–September) and leaf miners overwintered as adults and reappeared in the early spring. Damage ranging from 15% to 20% was observed on the leaves of J. regia. Further efforts related to C. roscipennella should concentrate on evaluating its geographic distribution and its impact on walnut trees. Several species of parasitoids were reared from infested mines, with specimens belonging to the genus Chrysocharis Förster, 1856 (Hymenoptera: Eulophidae) and Itoplectis maculator (Fabricius, 1775) (Hymenoptera: Ichneumonidae). These species provided excellent control of leaf miner larvae, and out of 10 larvae, seven were found parasitized by the parasitoids and higher numbers of specimens were found with relative higher frequencies. [ABSTRACT FROM AUTHOR]

The walnut industry in Argentina has grown in recent years, especially in northern Patagonia. However, this expansion has also brought new challenges, including the emergence of diseases threatening the health and productivity of walnut plantations. One of the most important diseases affecting walnut crops worldwide is 'ink disease' or 'walnut dieback'. The aim of this study was to characterize ink disease, identify the aetiological agents, and estimate its incidence in walnut orchards of northern Patagonia, Argentina. Symptomatic trees were observed in the seven surveyed walnut orchards, showing a range of symptoms, including chlorosis and wilting, stem cankers and desiccation. In vivo assay and molecular analyses revealed that not only Phytophthora (P.) but also Phytopythium (Ph.) species are the causal agents of the disease, with P. drechsleri, Ph. mercuriale and Ph. vexans being the most virulent over the commonly used rootstock Juglans hindsii. Notably, Ph. vexans was the most frequently isolated pathogen, suggesting its prevalence and potential impact on the regional walnut industry. Overall, this study provides critical insights into the prevalence and impact of Phytophthora and Phytopythium species on walnut health in northern Patagonia. The presence of multiple pathogenic oomycete species raises concerns about the health of walnut orchards, as well as the potential risk of pathogen transmission to other fruit crops in the region. The findings will help growers to develop better cultural practices and implement measures to guarantee the sustainability of the walnut industry in Patagonia. [ABSTRACT FROM AUTHOR]

Juglans regia L. is a fragrant transitory tree. Numerous health advantages are linked to the different components of the tree's phytochemistry, which has been the subject of substantial research. The current study evaluated the chemical composition of Jordanian Juglans regia Linn. acetonitrile extracts. The extract from the Juglans regia L. juvenile fruit, which grows in Amman, Jordan, was examined to determine its photochemical components. The extract was subjected to high-performance liquid chromatography-tandem mass spectrometry analysis. The fruit was harvested in May 2023. The juvenile fruit was extracted using Soxhlet, yielding 5.5 per cent. The semi-quantitative analysis identified secondary metabolites, including tannins. The total phenol content reached 9.83 gallic acid equivalents. Spectrophotometric analysis assessed antiradical activity after 2,2-diphenyl-1-picrylhydrazyl reduction, with an IC50 value of 0.75 mg/mL. The study revealed 79 chemical compositions, including gingerol, hyperoside flavonoids, prostaglandin derivatives, quercetin, naringenin, and ginkgolic acid II. These compounds have previously shown antibacterial, anti-inflammatory, and ulcer-prevention properties. Overall, this work shows that several phenolic acids, flavonoids, and fatty acids were identified that correspond to the pharmacological action of Juglans regia L. immature fruit extract previously described. The structural elucidation of unknown peaks requires more research. [ABSTRACT FROM AUTHOR]

Juglans regia L. is a exotic nut widely used as functional food owing to its multi-nutritional qualities. It is generally found in Southeast Europe extending towards the Himalayas and Southwest China. This historical plant is extensively used ethno-medicinally in the treatment of digestive, respiratory, cardiovascular and skin diseases. Its seeds are highly proteinaceous and polyphenolic containing triacylglycerol-rich oil especially mono and polyunsaturated fatty acids. The diverse lipid profile of the walnut has attracted the researchers of the decade towards scientific validation of its traditional aspects and isolation of important chemical compounds for improving human health. The present review comprehends the ameliorative effect of Juglans regia on various chronic diseases including cancer, gut dysbiosis, cardiovascular and neurodegeneration concerning its specific chemical profile. [ABSTRACT FROM AUTHOR]

The codling moth (Cydia pomonella) has a major effect on the quality and yield of walnut fruit. Plant defences respond to insect infestation by activating hormonal signalling and the flavonoid biosynthetic pathway. However, little is known about the role of walnut husk hormones and flavonoid biosynthesis in response to C. pomonella infestation. The phytohormone content assay revealed that the contents of salicylic acid (SA), abscisic acid (ABA), jasmonic acid (JA), jasmonic acid-isoleucine conjugate (JA-ILE), jasmonic acid-valine (JA-Val) and methyl jasmonate (MeJA) increased after feeding at different time points (0, 12, 24, 36, 48, and 72 h) of walnut husk. RNA-seq analysis of walnut husks following C. pomonella feeding revealed a temporal pattern in differentially expressed genes (DEGs), with the number increasing from 3,988 at 12 h to 5,929 at 72 h postfeeding compared with the control at 0 h postfeeding. Walnut husks exhibited significant upregulation of genes involved in various defence pathways, including flavonoid biosynthesis (PAL, CYP73A, 4CL, CHS, CHI, F3H, ANS, and LAR), SA (PAL), ABA (ZEP and ABA2), and JA (AOS, AOC, OPR, JAZ, and MYC2) pathways. Three gene coexpression networks that had a significant positive association with these hormonal changes were constructed based on the basis of weighted gene coexpression network analysis (WGCNA). We identified several hub transcription factors, including the turquoise module (AIL6, MYB4, PRE6, WRKY71, WRKY31, ERF003, and WRKY75), the green module (bHLH79, PCL1, APRR5, ABI5, and ILR3), and the magenta module (ERF27, bHLH35, bHLH18, TIFY5A, WRKY31, and MYB44). Taken together, these findings provide useful genetic resources for exploring the defence response mediated by phytohormones in walnut husks. [ABSTRACT FROM AUTHOR]

Botryosphaeriaceae species are the major causal agents of walnut dieback worldwide, along with Diaporthe species. Botryosphaeria dothidea and Neofusicoccum parvum are the only two Botryosphaeriaceae species associated with this recently emergent disease in France, and little is known about their diversity, structure, origin and dispersion in French walnut orchards. A total of 381 isolates of both species were genetically typed using a sequence-based microsatellite genotyping (SSR-seq) method. This analysis revealed a low genetic diversity and a high clonality of these populations, in agreement with their clonal mode of reproduction. The genetic similarity among populations, regardless of the tissue type and the presence of symptoms, supports the hypothesis that these pathogens can move between fruits and twigs and display latent pathogen lifestyles. Contrasting genetic patterns between N. parvum populations from Californian and Spanish walnut orchards and the French ones suggested no conclusive evidence for pathogen transmission from infected materials. The high genetic similarity with French vineyards populations suggested instead putative transmission between these hosts, which was also observed with B. dothidea populations. Overall, this study provides critical insight into the epidemiology of two important pathogens involved in the emerging dieback of French walnut orchards, including their distribution, potential to mate, putative origin and disease pathways. [ABSTRACT FROM AUTHOR]

Anthelmintic resistance in livestock animals has been spreading across the world in prevalence and severity. As a result, researchers are exploring alternative strategies to combat this issue, and one promising avenue is the utilization of medicinal plants. This study aims to investigate the anthelmintic efficacy of the crude ethanolic extract (CEE) derived from the leaves of Juglans regia against one of the most detrimental nematode parasites affecting poultry, namely Ascaridia galli (A. galli). For the in vitro studies, adult A. galli worms were collected from the naturally infected chickens and the efficacy of CEE was measured at the concentration of 25, 50, and 100 mg/ml using adult worm motility inhibition (WMI) assay. In addition, levamisole (0.55 mg/ml) was used as the positive control. Likewise, Phosphate buffered saline (PBS) was used as the negative control. For the in vivo studies, CEE of J.regia at the doses of 500, 1000, and 2000 mg/kg were evaluated in chickens experimentally infected with A. galli. The anthelmintic efficacy was monitored using faecal egg count reduction (FECR) and worm count reduction (WCR) assays. In vitro studies revealed significant (P < 0.001) anthelmintic effects of CEE of J.regia on the motility of A. galli worms at different hours post-exposure. At the concentration of 100 mg/ml, CEE resulted in 96.5% inhibition of worm motility at 24 h post-exposure. While the synthetic anthelmintic drug, levamisole caused the highest inhibition of worm motility (100%) at the same time period. The in vivo anthelmintic activity of CEE of J. regia demonstrated a maximum effect on day 14 post-treatment by inducing 67.28% FECR and 65.03% WCR. We observed no significant difference (P > 0.05) in worm counts between the negative control group and the chickens treated with CEE at the dosage of 500 mg/kg. Together, the results of the present study suggest that CEE of J. regia leaves possess anthelmintic properties and could be a potential source of novel anthelmintic compounds for controlling helminth parasites. [ABSTRACT FROM AUTHOR]

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Copyright of Revista de la Sociedad Entomológica Argentina is the property of Sociedad Entomologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Walnuts have substantial economic value and are of significant interest being a wild-cultivated species. The study has re-sequenced the entire genome of the wild walnut, aligning it with the walnut reference genome, to identify 2,021,717 single nucleotide polymorphisms (SNPs). These were used to examine the genetics of 130 wild walnut samples collected from three countries. Utilizing structural and principal component analysis, the walnut samples from Central Asia were classified into four populations: Ili ah in Xinjiang (I), Dushanbe region in Tajikistan (II), Sary-Chelek, Arslanbob in Kara-Alma regions of Kyrgyzstan (III), and Kok-Tundy region of Kyrgyzstan (IV). The 4 groups showed large differences in nucleotide diversity, population differentiation, and linkage disequilibrium decay, as well as gene flow among them. The present geographic distribution of these populations does not align with the genetic distribution pattern as the populations of Central Asian wild walnuts have experienced similar population dynamics in the past, i.e., the highest effective population size at ca. 6 Ma, two sharp population declines at 6 and 0.2 Ma, and convergence at ca. 0.2 Ma. The genetic distribution patterns are better explained by human activity, notably through archaeological findings of walnut use and the influence of the Silk Road, rather than by current geographic distributions. [ABSTRACT FROM AUTHOR]

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Over a century ago, there are anecdotal stories of the use of therapeutic anthelminthic plants, such as papaya (Carica papaya) against cestode infections. Various studies have explored the efficacy of traditional plants in the inactivation of protoscolices and have reported the scolicidal effect of plants. Further, these plants have relatively lower side effects compared to chemotherapeutic agents and are suggested to be used for treatment of this disease in humans as well. Thus, in the present study the in vitro scolicidal effect of C. papaya and J. regia on Echinococcus granulosus protoscolices was explored from sheep, goat and human cysts in Jammu region of North Western Himalayas.The ethanolic extracts of J. regia and C. papaya showed significant scolicidal activity against E. granulosus, under in vitro conditions with reference to the known standard drug “praziquantel”. Against J. regia, highest mortality was observed at 30 mg/ml concentration at different exposure time as 10 min. (88.58%), 20 min. (91.24%), 30 min. (93.16%) and 40 min. (96.64%). Against C. papaya, highest mortality was observed at 30 mg/ml concentration at different exposure time as 10 min. (82.95%), 20 min. (85.83%), 30 min. (90.23%) and 40 min. (92.95%). [ABSTRACT FROM AUTHOR]

Copyright of Biotechnology Bulletin is the property of Biotechnology Bulletin Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Batocera horsfieldi (Hope) (Coleoptera: Cerambycidae) is an important pole borer pest. It causes serious harm to various hosts, particularly Juglans regia L. (Juglandaceae). In this study, headspace solid‐phase microextraction (HS‐SPME), gas chromatography–mass spectrometry (GC–MS), and electroantennogram (EAG) responses were combined to examine the mechanism by which B. horsfieldi adults locate their host, J. regia. The results showed that J. regia contained 65 volatile compounds in all, with 36 and 42 volatile substances in bark and leaves, respectively. Moreover, terpenes accounted for the largest relative content among the volatile compounds of bark and leaves, 43.4 and 78.9%, respectively. Ten of 19 selected volatile components elicited significant EAG responses in adult B. horsfieldi, which indicated that the pest may prefer certain volatile compounds when selecting a host. Sex and volatile concentration affected the responses of B. horsfieldi. Male adults had the strongest EAG responses to 1‐octen‐3‐ol, whereas female adults had the strongest EAG responses to linalool. Host selection in B. horsfieldi was somewhat positively associated with the concentrations of the effective volatile compounds in the host. Furthermore, B. horsfieldi showed varying preferences for isomers. This work provided data support for the development of insect attractants, and laid a theoretical foundation for the ecological protection of local forestry. [ABSTRACT FROM AUTHOR]

The current study investigated the impact of cold stress on the morphological, physiological, and phytochemical properties of Juglans regia L. (J. regia) using in vitro microclone cultures. The study revealed significant stress-induced changes in the production of secondary antioxidant metabolites. According to gas chromatography–mass spectrometry (GC–MS) analyses, the stress conditions profoundly altered the metabolism of J. regia microclones. Although the overall spectrum of metabolites was reduced, the production of key secondary antioxidant metabolites significantly increased. Notably, there was a sevenfold (7×) increase in juglone concentration. These findings are crucial for advancing walnut metabolomics and enhancing our understanding of plant responses to abiotic stress factors. Additionally, study results aid in identifying the role of individual metabolites in these processes, which is essential for developing strategies to improve plant resilience and tolerance to adverse conditions. [ABSTRACT FROM AUTHOR]

Imagine consuming a daily diet rich in fatty acids to help treat diseases such as hypertension and obesity. This concept presents an attractive paradox. In particular, consuming walnut kernels is beneficial for treating diseases associated with metabolic syndrome (MetS), including type 2 diabetes, cardiovascular disease, dyslipidemia, and obesity. Different parts of the Juglans regia tree (family Juglandaceae), including its leaves, green husks, bark, and septum, have shown promising effects on pathological conditions related to MetS. The therapeutic advantages of consuming walnut kernels for MetS can be attributed to the presence of polyunsaturated fatty acids and polyphenolic compounds such as juglone and ellagic acid. Diets enriched with walnut kernel have a positive impact on MetS complications by reducing diastolic blood pressure, improving blood lipid profiles, lowering fasting blood sugar levels, and increasing insulin sensitivity. The potential cellular mechanisms responsible for these benefits involve activating the cholesterol hemostasis pathway by inhibiting sterol regulatory element‐binding proteins (SREBPs), proprotein convertase subtilisin/kexin type 9 (PCSK9), and cholesteryl ester transfer protein (CETP). Furthermore, other by‐products of walnuts, such as leaves and green husks, have also demonstrated effectiveness in managing MetS. These findings highlight the potential of incorporating walnut‐based products into our diets as a natural approach to combating MetS and its complications. [ABSTRACT FROM AUTHOR]

Dieback of fruiting spurs, stems and branches of walnut trees (Juglans regia L.), caused by Botryosphaeriaceae, is widespread in walnut orchards in Australia. Five species of Botryosphaeriaceae (Diplodia seriata, Dothiorella omnivora, Neofusicoccum macroclavatum, N. parvum, and Spencermartinsia viticola) were recovered from the Australian walnut orchards in a previous study, with D. seriata and N. parvum being the most prevalent. The present study evaluated inhibitory effects of ten fungicides on mycelium growth of those five species and on conidium germination of D. seriata and N. parvum. It investigated the preventative and curative efficacy of selected fungicides on disease incidence in glasshouse and field trials. In vitro experiments showed that nine of the fungicides reduced mycelium growth, and all ten inhibited conidium germination, but to varying extents. Tebuconazole, prochloraz manganese chloride, fluazinam, fludioxonil and pyraclostrobin were the most effective for inhibiting mycelium growth (EC50 < 0.14 µg a.i. mL-1), whereas pyraclostrobin, fluxapyroxad, fluopyram, penthiopyrad and tebuconazole were the most effective for inhibiting conidium germination (EC50 < 2.2 µg a.i. mL-1). In planta experiments with five fungicides confirmed that preventative treatments had greater efficacy than curative treatments. A field trial with four commercial fungicide formulations demonstrated that tebuconazole and tebuconazole + fluopyram provided protection of walnut trees for the longest period. The field trial also confirmed the efficacy of pyraclostrobin and the inhibitory effect of fluazinam. This study is the first in Australia to evaluate fungicides in different classes and with different modes of action for efficacy against Botryosphaeriaceae recovered from walnut orchards in Australia, and provides a wider selection of active ingredients for a fungicide rotation programme than that which is currently available to the Australian walnut industry. [ABSTRACT FROM AUTHOR]

The sulfate transporter (SULTR) is responsible for the transport and uptake of sulfate, which plays an indispensable role in the growth cycle of plants and adaptation to plant stress. However, there are few reports on the response and regulation of SULTR gene family members in walnuts (Juglans regia L.) to sodium selenate, low temperatures, high temperatures, and simulated drought stress. In this study, the whole genome of the SULTR genes family in walnuts was identified and analyzed by the bioinformatics method. The results show that the walnut genome contains seventeen JrSULTR genes, which are unevenly distributed on eight chromosomes and can be divided into four subfamilies. Cis-acting elements that respond to stress and participate in the regulation of plant hormones were found in the promoter sequence of the JrSULTR genes. The analysis of transcriptome data showed that the expression of JrSULTR1.2b was significantly upregulated under sodium selenate treatment, and the results of qRT-PCR analysis were basically consistent with the transcriptome data. The expression of JrSULTR3.1a and JrSULTR3.4b increased with the prolongation of simulated drought stress time. The transcription levels of JrSULTR1.2b and JrSULTR3.1a were significantly increased after low-temperature treatment. After 9 h of high-temperature treatment, the expression levels of JrSULTR3.1a and JrSULTR3.3 were significantly increased. JrSULTR1.2b and JrSULTR3.1a showed significant expression specificity under stress treatment. At the same time, we also performed subcellular localization of these two genes, which was consistent with the predicted results and was in the cell membrane, and their regulatory functions need to be further studied. These studies laid the foundation for us to explore the specific function of the JrSULTR genes in alleviating abiotic stress in walnuts. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia L.) is a monoecious species and although it exhibits self-compatibility, it presents incomplete overlap of pollen shed and female receptivity. Thus, cross-pollination is prerequisite for optimal fruit production. Cross-pollination can occur naturally by wind, insects, artificially, or by hand. Pollen has been recognized as one possible pathway for Xanthomonas arboricola pv. juglandis infection, a pathogenic bacterium responsible for walnut blight disease. Other than the well-known cultural and chemical control practices, artificial pollination technologies with the use of drones could be a successful tool for walnut blight disease management in orchards. Drones may carry pollen and release it over crops or mimic the actions of bees and other pollinators. Although this new pollination technology could be regarded as a promising tool, pollen germination and knowledge of pollen as a potential pathway for the dissemination of bacterial diseases remain crucial information for the development and production of aerial pollinator robots for walnut trees. Thus, our purpose was to describe a pollination model with fundamental components, including the identification of the "core" pollen microbiota, the use of drones for artificial pollination as a successful tool for managing walnut blight disease, specifying an appropriate flower pollination algorithm, design of an autonomous precision pollination robot, and minimizing the average errors of flower pollination algorithm parameters through machine learning and meta-heuristic algorithms. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Slovenica is the property of Biotechnical Faculty of the University of Ljubljana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, unprecedented health challenges are urging novel solutions to address antimicrobial resistance as multidrug-resistant strains of bacteria, yeasts and moulds are emerging. Such microorganisms can cause food and feed spoilage, food poisoning and even more severe diseases, resulting in human death. In order to overcome this phenomenon, it is essential to identify novel antimicrobials that are naturally occurring, biologically effective and increasingly safe for human use. The development of gemmotherapy extracts (GTEs) using plant parts such as buds and young shoots has emerged as a novel approach to treat/prevent human conditions due to their associated antidiabetic, anti-inflammatory and/or antimicrobial properties that all require careful evaluations. Seven GTEs obtained from plant species like the olive (Olea europaea L.), almond (Prunus amygdalus L.), black mulberry (Morus nigra L.), walnut (Juglans regia L.), blackberry (Rubus fruticosus L.), blackcurrant (Ribes nigrum L.) and bilberry (Vaccinium myrtillus L.) were tested for their antimicrobial efficiency via agar diffusion and microbroth dilution methods. The antimicrobial activity was assessed for eight bacterial (Bacillus cereus, Staphylococcus aureus, Salmonella enterica subsp. enterica, Proteus vulgaris, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Listeria monocytogenes), five moulds (Aspergillus flavus, Aspergillus niger, Aspergillus ochraceus, Penicillium citrinum, Penicillium expansum) and one yeast strain (Saccharomyces cerevisiae). The agar diffusion method revealed the blackberry GTE as the most effective since it inhibited the growth of three bacterial, four moulds and one yeast species, having considered the total number of affected microorganism species. Next to the blackberry, the olive GTE appeared to be the second most efficient, suppressing five bacterial strains but no moulds or yeasts. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were then determined for each GTE and the microorganisms tested. Noticeably, the olive GTE appeared to feature the strongest bacteriostatic and bactericidal outcome, displaying specificity for S. aureus, E. faecalis and L. monocytogenes. The other GTEs, such as blueberry, walnut, black mulberry and almond (the list indicates relative strength), were more effective at suppressing microbial growth than inducing microbial death. However, some species specificities were also evident, while the blackcurrant GTE had no significant antimicrobial activity. Having seen the antimicrobial properties of the analysed GTEs, especially the olive and black mulberry GTEs, these could be envisioned as potential antimicrobials that might enhance antibiotic therapies efficiency, while the blackberry GTE would act as an antifungal agent. Some of the GTE mixtures analysed have shown interesting antimicrobial synergies, and all the antimicrobial effects observed argue for extending these studies to include pathological microorganisms. [ABSTRACT FROM AUTHOR]

Introduction: Juglans regia Linn. and Carya illinoinensis (Wangenh.) K. Koch are nut‐producing plant species of the Juglandaceae family. Bioactive compounds like naphthoquinones, tetralones, and diarylheptanoids are dominant in these species. Objective: The study aimed to develop and validate a fast and sensitive analytical method by ultrahigh‐performance liquid chromatography diode array detection mass spectrometry (UHPLC‐DAD‐MS) for quantification and identification of bioactive compounds in fruit pericarps and leaves of J. regia and C. illinoinensis collected from two different states of north India. Methodology: The dried pericarps of J. regia and C. illinoinensis (500 mg) were extracted with ethyl acetate–methanol (50:50 v/v, 20 mL, 50°C, 30 min) by ultrasonication and analysed by ultrahigh‐performance liquid chromatography diode array detection quadrupole time‐of‐flight tandem mass spectrometry (UHPLC‐DAD‐QTOF‐MS/MS) for qualitative and quantitative examination of phytoconstituents. The method was validated according to International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human use (ICH) guidelines for linearity, precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ). Results: Here, we report the quantification of dihydrophaseic acid (1), 4,5‐dihydroxytetralone (2), 4,8‐dihydroxytetralone (3), 5,8‐dihydroxy‐3‐methoxytetralone (4), and juglanin A (5) in the pericarps and leaves of J. regia and C. illinoinensis. Furthermore, using the hyphenated analytical method, a total of 62 compounds were tentatively characterised in different samples. The principal component analysis (PCA) showed diversity between the analysed sample's composition. Also, the study evaluated the variation of bioactive compounds among different parts of J. regia and C. illinoinensis collected from different regions of northern India by UHPLC‐DAD‐QTOF‐MS/MS. Conclusion: The developed method is simple, rapid, and selective for the identification and characterisation of bioactive molecules. A rapid UHPLC‐DAD method was developed and validated for the quantification of five compounds in fruit pericarps and leaves samples of J. regia and C. illinoinensis. A total of 62 compounds were tentatively characterized in samples collected from different locations using UHPLC‐DAD‐QTOF‐MS/MS. [ABSTRACT FROM AUTHOR]

Walnut is one of the most important nuts regarding their production and consumption. The available but uncharacterized genetic resources of walnut are important for the development and breeding of local varieties. Greece holds an important number of genetically uncharacterized walnut landraces, especially within the area of Parnon, which is considered to play a significant role as an in situ gene bank, due to its unique location traits. However, the genetic characterization and further use of these resources has been insufficient, due to the absence of genetic studies. In this study, we implemented SSR molecular markers, both to genetically characterize the walnut tree genetic diversity of the Parnon area and to identify its unique genetic structure, which will form the starting material for subsequent breeding programs. Overall, high levels of genetic variation were found among the individual walnut accessions that were collected in the Parnon mountain region. [ABSTRACT FROM AUTHOR]

As walnut trees (Juglans spp.) are of high economic importance, considerable attention has been given to invasive pests of these trees in Europe. In 2016, Dryocoetes himalayensis Strohmeyer, 1908, an alien bark beetle originating from the Himalayas region of India, already present in several European countries, was confirmed to have attacked walnut trees in the Czech Republic. Within the present study, we (i) surveyed the current distribution of D. himalayensis in the Czech Republic, (ii) examined D. himalayensis phenology by rearing it in trap logs, and (iii) investigated tree level habitat preferences of the species in two study stands with 180 black walnut (Juglans nigra L.) trees and 66 common walnut (Juglans regia L.) trees sampled. The present study documented the species to be relatively widespread in some warmer lowland regions of the Czech Republic (42 localities found) and to reach high abundance locally. Almost 15 thousand D. himalayensis individuals reared from the trap logs showed the species emerging throughout the whole vegetation period with a distinctive peak in June. Even though the species is able to develop in thin stems (diameter <5 cm), it is most numerous in thicker trunk bases and also preferably attacks trees of higher diameters. The species preferred common walnut trees (its native host) with decreased vitality. In contrast, black walnut trees (North American species) were attacked regardless of their vitality, but the vitality of occupied trees successively decreased. Based on our results, D. himalayensis should be assumed as a considerable pest of walnut trees (particularly black walnuts), which might become of significant importance in its European invasive range in the future, and thus substantial attention should be given to it. [ABSTRACT FROM AUTHOR]

The knowledge of transcription factor (TF) families is an important aspect in the post-genomic era. The U-box TF play pivotal role in plant development and growth. Although, the U-box gene family has been extensively investigated in many plants, it has not been systematically explored in Juglans regia. This study aims to identify U-box TF in J. regia genome and explore their gene expression and evolutionary relationship. A sum of 88 candidate JrU-box genes were identified in the Juglans database and classified into 10 groups. These JrU-box genes were unevenly distributed on J. regia's 16 chromosomes, with three chromosomes duplicated as tandem repeats, indicating an expansion of the similar to Arabidopsis thaliana. Motif composition and conserved domain analysis showed that the JrU-box genes contain two conserved motifs (1 and 2) and three conserved protein domains (U-box, RING U-box, and Zf-RING U-box), respectively. In addition, the structural analysis showed that most JrU-box genes have one exon and 12 introns. The determined JrU-box gene expression profiles indicated their potential involvement in various developmental and physiological processes. Specifically, 33 JrU-box genes were highly expressed in reproductive tissues (female flower, male flowers, and fruit) of J. regia, whereas, other identified genes were highly expressed in vegetative tissues, suggesting that the JrU-box gene family plays a role in flower development. Hence, we can expect that JrU-box gene family may play a major role in J. regia overall development. [ABSTRACT FROM AUTHOR]

Juglans regia is a medicinal plant widely used in traditional medicine and it. It is applied for healing a numerous ailment such us diabetes, digestive problems, hypertension, and gout diseases. This review aims to highlight the importance of Juglans regia as source of nutritional and bioactive compounds. Mechanisms of antimicrobial, antioxidant, anti-inflammatory, antidiabetic, and anticancer activities of Juglans regia leaves, fruit, septum kernels, flowers, bark, and husk have been discussed. Juglans regia fruits have an important nutritive value allowed by their richness in lipids and proteins. Medicinal properties of Juglans regia are certainly due to its bioactive compounds. Indeed, Juglans regia leaves, husks, flowers, bark, and roots contain several secondary metabolites including polyphenols, flavonoids, and glycosides. Pharmacological investigations reported by the literature demonstrated that Juglans regia exhibit different biological activities such as antioxidant, anti-inflammatory, anti-diabetic, antitumoral, antifungal, and antibacterial effects, in vitro, in vivo and in clinical trials. Mechanisms of bioactive compound action include ROS neutralization, proinflammatory mediators and enzyme inhibition, insulin levels increase, regulation of apoptosis, and cell cycle disruption. Biological properties were remarkably correlated with bioactive compounds containing in Juglans regia. Therefore, with its important nutritive values and its bioactive compounds, Juglans regia could be considered as a relevant functional food. [ABSTRACT FROM AUTHOR]

Leaves of species of the genus Juglans L. of the Juglandaceae family hold promise as officinal medicinal plant materials whose preparations have an antimicrobial and general tonic effect. In our opinion, the contribution to the antimicrobial activity is made, along with naphthoquinones, by the flavonoids contained in the leaves of various species of the genus Juglans L. This creates the need to determine the chemical composition of the leaves of species of the genus Juglans L. using modern methods of analysis. This article discusses the results of studying the component composition of the leaves of Juglans nigra L., Juglans regia L., and Juglans cinerea L. by microcolumn high performance liquid chromatography (HPLC) at an analytical wavelength of 360 nm. The chromatographic separation conditions were established for the analysis of extracts from the leaves of the species of the genus Juglans L. It was determined that use of HPLC allows identification in the leaves of Juglans nigra L. of the dominant and diagnostically significant for this raw material flavonoids, myricitrin and quercitrin. Also, this medicinal plant was found to contain the aglycone of myricitrin, myricetin. A similar flavonoid profile was revealed for two medicinal plant raw materials represented by leaves of Juglans regia L. and of Juglans cinerea L. Hyperoside, quercitrin, and juglanin were found in these species. [ABSTRACT FROM AUTHOR]

The common walnut (Juglans regia L.), a species of significant economic and ecological importance, along with its variant, holds developmental value. Simple sequence repeat (SSR) markers are used as an effective method for material identification due to their co-dominant inheritance. In this work, a total of 357629 SSR loci were searched based on previously published walnut genome sequences, with a density of 662.28 (SSRs/Mb). The majority of all these loci were found to be single nucleotide A/T (58.49%), followed by the dinucleotide AT (19.48%). Based on the results of genome-wide SSR site design, 22 effective primer pairs were designed and screened to analyze the genetic diversity of 48 wild walnut samples from three countries. Each locus had an average of 5.17 effective alleles (Ne), with an average polymorphism information content (PIC) of 0.71, average heterozygosity (He) of 0.52, and average genetic differentiation index (Fst) of 0.09. The analysis of 48 wild walnut samples from three countries (Kyrgyzstan, Tajikistan, and China) using the unweighted pairwise clustering method and arithmetic mean (UPGMA) along with principal coordinate analysis revealed the division of all samples into three groups. In summary, these novel SSR markers serve as a reference for the identification of wild walnut germplasm in Central Asia and for the development and utilization of wild walnut seed resources. [ABSTRACT FROM AUTHOR]

Introduction: The internal septum of J.regia is traditionally used to control diabetes, and its effectiveness has been shown in animal studies. Accordingly, human clinical trials are needed to confirm its effectiveness on hemoglobin A1c (HbA1c), fasting blood sugar (FBS), blood insulin level, and insulin resistance as a complementary for better control of type 2 diabetes. Methods: This study was a randomized, double-blinded, controlled trial. The lyophilized powder of extract of the internal septum of J.regia was used to fill the capsules. Sixty type 2 diabetic patients were randomly divided into two groups. 500 mg capsules three times daily before meal was added to their routine drug regimen, and HbA1c, FBS, and blood insulin level were checked at the baseline and after three months. Results: Sixty patients completed the study. The mean(±SD) age of patients was 49.1(10.2) and 50.9(12.7) years in the placebo and J.regia groups, respectively. We observed that J.regia internal septum increases the level of HbA1c by about 0.02 units, but this effect was not significant (MD=0.02,95%CI=-0.36 to 0.40, P =0.93). Regarding the impact of capsules on insulin level, it seems that J.regia -containing capsules can raise insulin level by one unit. However, it was not significant (MD=1.01,95%CI=-0.86 to 2.88, P =0.28). As for FBS, it can cause a decrease of four units, but this effect is also not significant (MD=-3.98,95%CI=-18.33 to 10.37, P =0.58). Conclusion: Based on our study, the internal septum of J.regia has no significant effect on HbA1c, FBS, and insulin resistance. Moreover, no specific adverse reaction was observed in any of the patients. [ABSTRACT FROM AUTHOR]

Anthracnose, caused by Ophiognomonia leptostyl Fr., is one of the most destructive walnut (Juglans regia L.) foliar diseases in the world. To facilitate development of cultivars in new growing areas, four recently released cultivars in Iran ('Alvand', 'Chaldoran', 'Caspian', and 'Persia'), a local promising genotype (C25), 'Hartley', 'Ronde de Montignac', and K72 were examined for their response to the anthracnose attack. Fully expanded leaflets of grafted plants were inoculated by fungal conidia in two consecutive years. The number and size of necrotic spots were recorded at 15-day intervals until 45 days after inoculation. According to the data of 30th day, the maximum number of necrotic lesions belonged to 'Alvand' while the largest spots developed on K72 and 'Chaldoran'. Cultivars were categorized into six susceptibility classes depending on Necrotic Leaflet Area (NLA). The average of NLA ranged from 0.61% ('Ronde de Montignac') to 99.94% (in K72). All tested cultivars, except 'Ronde de Montignac' and 'Hartley', were susceptible, but symptoms development and disease severity varied among the cultivars. 'Persia' exhibited a low level of infection and was relatively resistant. 'Caspian' with an average NLA of 20% was slightly susceptible. 'Alvand' and C25 grouped as susceptible and moderately susceptible, respectively. K72 and 'Chaldoran' showed the maximum level of infection. The amount of disease was intensified in 'Caspian', C25 and 'Alvand' between the days of 30-45 after inoculation, while 'Ronde de Montignac', 'Hartley' and 'Persia' appeared consistently more resistant even 45 days after inoculation. These three cultivars could be used in integrated management approaches to control anthracnose in walnut orchards. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Geochemistry & Health is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, leaf essential oil effects on glutamate toxicity model formed in cortex neurons and LN405 cell cultures were investigated. Antidiabetic activity was evaluated by α-amylase and α-glucosidase inhibitions. MIC was used for antimicrobial activity. Seven groups were examined with MTT. Glutamate 10-5 mM in cortex showed 62% viability whereas oil viability did not increase in a dose-dependent manner and the highest viability rate was observed. There are four types of glandular trichomes in leaf anatomy of walnut. The oil exhibited half as much α-glucosidase inhibitory activity with an IC50 value of 8105 μg/mL, compared to positive control acarbose (IC50 = 4762 μg/mL). MIC of oil was determined to be 625 μg/mL against E. coli, C. albicans, and C. parapsilosis, whereas S. aureus exhibited a MIC of 1250 μg/mL. Major compounds of oil were found as β-pinene (17.6%), α-pinene (11.3%), β-eudesmol (8.6%), and caryophyllene oxide (6.2%). [ABSTRACT FROM AUTHOR]

Introduction: There is a progressive increase in the patients of dental caries and periodontitis in the recent years. The main emphasis is laid on avoiding the accumulation and inducing the elimination/suppression of caries-causing microbes in the oral cavity. A variety of antimicrobial agents are incorporated into oral hygiene products but these products come up with their own disadvantages. Natural products prove to be biocompatible with medicinal properties. Aims and Objectives: The objective of the study is to access the antimicrobial activities of Juglans regia bark against dental caries and plaque. Also, antibacterial activity of Juglans bark is compared with oral rinses and systemic antibiotics. Material and Methods: The study sample consisted of 50 subjects and was divided into two groups. Group 1 consisted of 25 samples without caries and Group 2 also included 25 samples with caries. Both samples were in the age group 18-22 years. Plant samples of Juglans regia bark from Kashmir and Himachal were collected. Extracts containing both varieties were prepared and antibacterial activities of both groups were determined. Comparison of Juglans regia bark with antibiotics and mouthwashes was also done. Results and Conclusion: J. regia bark of both the varieties showed zone of inhibitions. Ethanol variety showed larger zone of inhibition than distilled water variety of both plaque and caries groups. Chlorhexidine showed satisfactory antimicrobial activity while Betadine showed none. Amoxicilline was effective but Metronidazole showed no activity against both groups. Bark of J. regia proved to be very beneficial against both plaque and caries bacteria without any side effects as both mouthwashes and antibiotics are harmful and cannot be used daily. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia) populations are considered a valuable genetic resource for genetic variability conservation and walnut cultivar improvement. In the current study, two walnut selections from Central Greece, "FM3" and "FM6", were evaluated for their characteristics to determine their perspective as new cultivars. Their main phenological and pomological characteristics were assessed according to IPGR (1994) and UPOV-TG/125/6 (1999) criteria for 10 consecutive years and compared with "Chandler". Results revealed that "FM3" presents high lateral flowering (70–80%), whereas "FM6" is 30–35%. Although the date of bud break and male blooming of both selections did not differ from "Chandler" (p > 0.05), the female blooming phase of "FM6" occurred earlier (p < 0.05) than "Chandler" and nut harvest was earlier than both "Chandler" and "FM3" (p < 0.05). Nut dimensions of both selections were higher than "Chandler" (p < 0.001). The mean in-shell nut weight and kernel weight of "FM3" were higher than "FM6" and "Chandler", and those of "FM6" were higher than "Chandler" (p < 0.001). Other positive nut characteristics were their light kernel color, the well kernel fill, and the easy removal of the kernel halves. Thus, the current results indicate that "FM3" and "FM6" could be considered promising gene pools in crossbreeding activities. [ABSTRACT FROM AUTHOR]

The weevil, Myllocerus fotedari Ahmad, 1974 (Coleoptera: Curculionidae) is widely recognised as one of the major walnut pests. Fungal pathogens have shown great potential for the management of some pest species. In the present study, the efficacy of three entomopathogenic fungi, namely Beauveria bassiana (Balsamo) Vuillemin, Metarhizium anisopliae sensu lato (Metchnikoff) Sorokin and Lecanicillium lecanii (Zimmerman) Zare and Gams were evaluated against the weevil, M. fotedari, under laboratory conditions. Each fungal suspension contained 1.0 × 109 spores of fungi in 1 mL. The experiment comprised of five treatments along with control (distilled water) and three replicates. An insecticide – chloropyrifos 20% emulsifiable concentrate (EC), was also used as positive control in the experiment. The experimental results revealed that the weevil, M. fotedari, showed mortality due to both virulence of entomopathogens and insecticide. The mortality caused by fungi varied from two days after treatment to eight days after treatment. However, the highest mortality of 100% was recorded for B. bassiana, followed by 85.1% for M. anisopliae after eight days of treatment. The efficacy of L. lecani was the lowest, leading to only 51.8% mortality, and was found significantly less virulent compared to the other two used entomopathogens. The present study is an attempt to use entomopathogens to control M. fotedari over conventional chemical insecticides. [ABSTRACT FROM AUTHOR]

Background/Objective: Juglans regia trees grow all over the Balkan peninsula and their fruit is used in human nutrition. The essential oil of J. regia leaves depends on seasonal and vegetational development. The objective of this study was to analyze the essential oil of J. regia green and yellow leaves and to determine the differences in chemical composition. Methods: The essential oils of green and yellow J. regia leaves were obtained by hydrodistillation. The chemical composition of the obtained essential oils was determined by gas chromatography-mass spectrometry. Results: The essential oil yield from green leaves was 0.02% and the yellow leaves yielded 0.01%. The essential oils obtained had different chemical composition. The main components of the essential oil of the green leaves were: sesquiterpene hydrocarbons (38.5%), oxygenated sesquiterpenes (23.3%), and monoterpene hydrocarbons (22.5%). The principal components of the yellow leaves essential oil were oxygenated sesquiterpenes (75.2%). Conclusion: The results obtained indicated a significant difference in the essential oil chemical composition of green and yellow leaves due to the irreversibility of senescence. [ABSTRACT FROM AUTHOR]

Lignin deficiency in the endocarp of walnuts causes kernel bare, leads to inconvenient processing and transportation of walnuts, and easily produces insect damage and mildew, thereby affecting the quality of walnuts. Cinnamyl alcohol dehydrogenase (CAD) is one of the key rate-limiting enzymes in lignin synthesis and plays an important role in the synthesis of lignin in the endocarp of walnut. However, knowledge about CAD gene family members and their evolutionary and functional characteristics in walnuts is limited. In this study, all 18 JrCADs were identified, and phylogenetic relationships, gene structure, protein motifs, collinearity analysis, and expression patterns of the JrCADs were also analyzed. All JrCADs could be divided into three groups based on the phylogenetic tree, gene structure, and motif analysis also support this grouping. Transcriptome data demonstrated that JrCADs have different expression patterns in walnut endocarps at different developmental stages. Combined with qRT–PCR data, we finally identified several candidate JrCADs involved in the process of endocarp sclerosis. This study showed that the JrCAD family members are highly conservative in evolutionary characteristics and they might participate in a variety of hormone responses. JrCAD17 and JrCAD18 are highly expressed in all periods of walnut endocarp harding, they are closely related to lignin accumulation. [ABSTRACT FROM AUTHOR]

This study examined the larvicidal effect of trunk-injected abamectin and emamectin benzoate against the walnut husk fly (Rhagoletis completa Cresson, 1929). Walnut trees in two locations in two years were injected with the pesticides at different concentrations. For the toxicokinetic studies, the active ingredient content was measured in the leaves, flowers, husks, and kernels, using a UHPLC-MS/MS analytical method. The walnut husk fly infestation rates were between 3 and 70% and 10 and 34% for abamectin and emamectin benzoate, respectively, and were much lower compared to those measured for the control. The active ingredient content in the walnut husk showed a positive correlation with the larvicidal effect. The injections had a measurable but unsatisfactory insecticidal effect in the second year, when the economic threshold was exceeded. Trace amounts of the active ingredients were detected in the flowers. The residue analysis showed a declining concentration trend in the leaves over time. The largest quantities were detected in the leaves (≤439 ng/g of abamectin; ≤19,079 ng/g of emamectin benzoate), with concentrations in the husks of orders of magnitude lower (≤5.86 ng/g; ≤50.19 ng/g). The measurements showed no active ingredient residue above the MRLs in either fresh or dried kernels. The results indicate that trunk injections of abamectin, as well as trunk injections of emamectin benzoate, have the potential to suppress walnut husk fly populations. [ABSTRACT FROM AUTHOR]

This article reports on the discovery of two invasive pathogens, Phytophthora acerina and Phytophthora palmivora, causing root rot, bleeding cankers, and dieback of English walnut trees in Italy. The decline of walnut orchards in Italy has been accompanied by an increase in reports of new diseases. Field surveys revealed a disease incidence of 36% and 40% in two orchards in the Veneto and Marche regions, respectively. The pathogens were identified through morphological, molecular, and phylogenetic analysis, and their pathogenicity was confirmed through inoculation trials. This is the first report of these pathogens on English walnut in Italy and worldwide. The researchers emphasize the importance of monitoring and controlling the introduction and spread of these pathogens to prevent further decline and yield reduction in walnut trees. [Extracted from the article]

In the present study, we designed and validated genome-wide polymorphic SSR markers (110 SSRs) by mining the walnut genome. A total of 198,924 SSR loci were identified. Among these, successful primers were designed for 162,594 (81.73%) SSR loci. Dinucleotides were the most predominant accounting for 88.40% (175,075) of total SSRs. The SSR frequency was 377.312 SSR/Mb and it showed a decreasing trend from dinucleotide to octanucleotide motifs. We identified 20 highly polymorphic SSR markers and used them to genotype 72 walnut accessions. Over all, we obtained 118 alleles that ranged from 2 to 12 with an average value of 5.9. The higher SSR PIC values indicate their robustness in discriminating walnut genotypes. Heat map, PCA, and population structure categorized 72 walnut genotypes into 2 distinct clusters. The genetic variation within population was higher than among population as inferred by analysis of molecular variance (AMOVA). For walnut improvement, it is necessary to have a large repository of SSRs with high discriminative power. The present study reports 150,000 SSRs, which is the largest SSR repository for this important nut crop. Scientific communities may use this repository for walnut improvement such as QTL mapping, genetic studies, linkage map construction, and marker-assisted selection. [ABSTRACT FROM AUTHOR]

AT-hook motif nuclear localization (AHL) proteins play essential roles in various plant biological processes. Yet, a comprehensive understanding of AHL transcription factors in walnut (Juglans regia L.) is missing. In this study, 37 AHL gene family members were first identified in the walnut genome. Based on the evolutionary analysis, JrAHL genes were grouped into two clades, and their expansion may occur due to segmental duplication. The stress-responsive nature and driving of developmental activities of JrAHL genes were revealed by cis-acting elements and transcriptomic data, respectively. Tissue-specific expression analysis showed that JrAHLs had a profound transcription in flower and shoot tip, JrAHL2 in particular. Subcellular localization showed that JrAHL2 is anchored to the nucleus. Overexpression of JrAHL2 in Arabidopsis adversely affected hypocotyl elongation and delayed flowering. Our study, for the first time, presented a detailed analysis of JrAHL genes in walnut and provided theoretical knowledge for future genetic breeding programs. [ABSTRACT FROM AUTHOR]

The Asian walnut moth, Garella musculana (Erschov, 1874) (Lepidoptera: Nolidae), is a major pest of walnut. Native to Central Asia, it was found to be invasive in 2008 in Sevastopol (Crimea) and nowadays widespread in Turkey, Bulgaria, Romania and Russia. Here, we account for the finding of G. musculana in NE Italy (Veneto region) in 2021, where adults were found in a light lamp, representing the first record of the Asian walnut moth for this country and Western Europe. Adult specimens were identified morphologically on both external characters and genitalia features. G. musculana larvae and damage were also observed on a plantation of Juglans regia L. (Fagales: Juglandaceae) located in Veneto in October 2021. A COI‐barcoding analysis was performed to attain a molecular characterization of our specimens and probate our morphological identification. However, because no sequence of G. musculana was present in major gene databases and the similarity of our sequences with those attributed to Garella ruficirra (Hampson, 1905) (Lepidoptera: Nolidae) made clear that these taxa deserved further scrutiny regarding their specific distinction. Some subtle differences in the male terminalia could be found between them and their vast geographic distributions, but the strong similarity in most features calls for further morphological and genetical insights on a broad set of samples to assess whether they represent two closely related, substantially parapatric species, or a unique, geographically varying entity. Solving this issue may turn out crucial in the identification and proper management of walnut moths of the genus Garella. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciências Agrárias is the property of Sociedade de Ciencias Agrarias de Portugal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)