Vitis Vinifera Research Articles

The Perpetual Impact of COVID-19 on the Geriatric Population's Quality of Life and Potential Preventive and Therapeutic Measures in Unani Medicine: An Evidence-based Review

Background: COVID-19 pandemic has affected the elderly population more severely than many other patient groups. Due to their constitutional weakness and co-morbidities, geriatric populations are more prone to complications and adverse outcomes, especially with a high viral load. The Unani system of medicine encompasses several guidelines for the prevention and treatment of epidemics, which are stratified for different types of people with respect to age, geography, and health status, among others. Objective: Since Unani drugs are both safe and efficient, it has been found that demand for them has surged since COVID. This paper aims to discuss the various immunomodulatory, longevity-promoting agents, and organ-specific tonics specified in Unani medicine for the care of the elderly, which may be helpful during epidemics, and also, to present the scientific evidence of their efficacy. Methods: A thorough assessment of the available literature was carried out utilizing several electronic databases, including PubMed, Science Direct, Web of Science, Wiley Online, Google Scholar, and Springer Link, using the terms "Geriatrics," "Elderly," "SARS-CoV-2," "Unani," and many others, up until October 2022. A total of 61 pertinent reviews were included. To gather information on epidemics and their specific response in geriatrics, monographs in Urdu, Arabic, and English were explored in addition to classic Unani texts such Al-Qanun fit Tibb (The Canon of Medicine), Kamil-us-Sana'at (Liber Regius), Kitab al-Hawi fit Tibb (Liber Continence), and others. Plant names were confirmed by “The Plant List” (www.theplantlist.org). Results: During pandemics, Unani medicine aims to promote and preserve the health of the elderly by regulating six important factors (Asbāb Sitta Ḍarūriyya), which include adopting a specific diet, regimen and drugs as effective prophylactic strategies. However, the role of Unani medicine in immunological regulation relies on major organ protection, viz., general body tonic, nervine tonic, heart tonic, and liver tonic. Several Unani single drugs, such as Sibr (Aloe barbadensis Mill.), Zafran (Crocus sativus L.), and Mur (Commiphora myrrh Nees.), and formulations, such as Khameera Marwareed, Tiryaq-i- Arba, and Habb-i- Jadawar have also been found to be very effective in validated scientific preclinical and clinical studies. Furthermore, Unani drugs have anti-inflammatory, analgesic, and tonic actions, contributing to their holistic efficacy. Conclusion: It is observed in this review that Unani medicine employs a holistic approach to the health protection of the elderly. There are various dietary recommendations, lifestyle modifications, regimental therapy, and pharmacotherapy prescribed as per the individual’s requirements and needs to reduce geriatric mortality in times of epidemics. Modern pharmacological studies have discovered many bioactive compounds in health-protective drugs prescribed in Unani medicine, such as Vitis vinifera L., Ziziphus jujube Mill., and many others, further substantiating the literature.

Impact of spray drying operating conditions on yield, secondary metabolites, antioxidant potential and storage quality of grape (Vitis vinifera L.) pomace powder

In the present investigation, spray drying independent operating conditions such as the inlet air temperature (A-IAT 130, 150 and 170 °C), outlet air temperature (B-OAT 60, 70 and 80 °C), needle speed (C-NS 3S, 4S, 5S), maltodextrin concentration (D-MD 10, 15, 20 %), pump speed (E-PS 5, 10, 15 mL/min) and water/grape pomace ratio (F-W/GP ratio 10, 15, 20) were optimized to develop the spray-dried grape pomace powder (SDGPP) with maximum yield. The impact of these conditions on total phenolic contents (TPC), total flavonoid contents (TFC), and antioxidant activity (DPPH· values) of SDGPP samples were analyzed. The independent spray drying factors (IAT, OAT, NS, MD, PS, and W/GP ratio) impart a strong direct effect (p ≤ 0.05) on powder yield, TPC, TFC, and DPPH· values. The interaction effects (A × B, A × C, A × D, A × E, A × F, B × C, B × D, B × E, B × F, C × D, C × E, C × F, D × E, D × F, and E × F) of independent variables were noted non-significant (p ≥ 0.05) for response values. After validation of the model and verification of results, the independents' variables were found in the range of 170 °C (IAT), 80 °C (OAT), 4S (NS), 15 % (MD), 10 mL/min (PS) and 15 (W/GP ratio) for yield (64.7 ± 1.18 %), TPC (7.66 ± 0.53 mg GAE/g), TFC (3.19 ± 0.30 mg CE/g) and DPPH· 140.3 ± 1.59 (100 µL/mL), respectively. The decrease in TPC, TFC, and DPPH· values of SDGPP samples was noted during 60 days of storage at 25 ± 2 °C and 65 ± 5 % RH (p ≤ 0.05) but not greater than unprocessed samples. It could be concluded that the protection of phenolic contents and retention of antioxidant activity of dried powders can be achieved at optimized spray drying conditions for discerning food and byproduct processing industries.

Pharmacotherapeutic potential of Vitis vinifera (grape) in age-related neurological diseases

Age-related neurological disorders (ANDs), including neurodegenerative diseases, are complex illnesses with an increasing risk with advancing years. The central nervous system's neuropathological conditions, including oxidative stress, neuroinflammation, and protein misfolding, are what define ANDs. Due to the rise in age-dependent prevalence, efforts have been made to combat ANDs. Vitis vinifera has a long history of usage to treat a variety of illness symptoms. Because multiple ligand sites may be targeted, Vitis vinifera components can be employed to treat ANDs. This is demonstrated by the link between the structure and action of these compounds. This review demonstrates that Vitis vinifera and its constituents, including flavonoids, phenolic compounds, stilbenoids and aromatic acids, are effective at reducing the neurological symptoms and pathological conditions of ANDs. This is done by acting as an antioxidant and anti-inflammatory. The active Vitis vinifera ingredients have therapeutic effects on ANDs, as this review explains.

Physiological responses of grapevine (Vitis vinifera var. ‘Pinot gris’) affected by different flavescence dorée genotypes: dynamics through the development of phytoplasma infection

Physiological responses of grapevine (Vitis vinifera var. ‘Pinot gris’) affected by different flavescence dorée genotypes: dynamics through the development of phytoplasma infection

Insights into Medieval Grape Cultivation in Al-Andalus: Morphometric, Domestication, and Multivariate Analysis of Vitis vinifera Seed Types

Understanding the origins and evolution of modern grapevine varieties in the Iberian Peninsula and western Europe necessitates an examination of the proportions of Vitis vinifera cultivars, their relationships with wild grapevine populations, and the utilization of seedless cultivars in al-Andalus. Employing morphometric studies, domestication indices, multivariate analysis, and Bayesian hypothesis testing, this study investigates several distinct seed types identified in materials from Roman and medieval deposits. These seeds exhibit a spectrum from highly domesticated to purely wild. Our findings reveal the predominance of Proles Occidentalis Negrul, and the presence of feral-like grapevines associated with Proles Euphratica. Additionally, we observe the continuous presence of wild grapevines related to Vitis sylvestris CC Gmelin throughout the studied period. Seeds exhibiting intermediate characteristics are documented, alongside the identification of “stenosperms”, suggesting anomalies in seed formation. Notably, the presence of Vitis vinifera raisins “stenospermocarpics” of the sultana type is suggested, potentially elucidating the absence of table grapes and raisins of the Proles Orientalis Negrul in the archaeological record, despite frequent mentions by medieval agronomy writers from al-Andalus.

Some Amino Acids Affect the Response of Grape (Vitis vinifera L.) Single Nodules In Vitro Multiplication

Organic nitrogen, which comes from amino acids, is absorbed and transported more rapidly than inorganic nitrogen by plant cells and tissues. Therefore, this study was conducted to evaluate the effect of some amino acids on the response of single nodes of grape Vitis vinifera L. Superior and Red globe cultivars were classified for in vitro multiplication to develop an efficient protocol for propagation of these two valuable species. The study included two experiments: first, the effect of adding three concentrations (0, 0.5, and 1) mg L-1 of Benzyl Adenine (BA) to the MS medium in the initiation stage. The second investigation utilized three amino acid types (glutamine, asparagine, and methionine) at five concentrations (0, 10, 20, 40, and 80) mg L-1 added to MS medium containing 2 mg L-1 of BA. Results indicated that the most significant newly initiated shoots (2.40 and 2.88) and the largest leaves number (7.90 and 5.88) for both cultivars, Superior and Red globe, respectively were obtained in a medium with 1 mg L-1 of BA. The multiplication results in eight weeks after cultivation showed that adding amino acid glutamine at 10 mg L-1 significantly increased the number of shoots/explant (6.60 and 6.00) and (29.50 and 38.30) leaves/explant for Red globe and Superior, respectively. The high amino acid concentrations (40 and 80) mg L-1 significantly reduced the studied growth parameters, especially the number of newly formed shoots. The results obtained from the present study exhibited the possibility of applying this modified protocol to the propagation of selected grape cultivars to encourage the expansion of the grape-growing industry in Iraq.

Classification and Status by Geological Periods Relicts, Rare Species of Zakatala and Belokan Districts

The article provides data on period III relicts and rare tree and shrub species common in the forest ecosystems of the Zakatala and Belokan districts of Azerbaijan, and their classification and status by geological periods is given. As a result of research and analysis, the species Taxus baccata L., Hedera pastuchovii Woronow ex Woronow and Smilax excelsa L. were included in the relicts of the Poltava flora. In the forest ecosystems of the study areas, 6 tree and shrub relict species belonging to 6 families and 6 genera of the subtropical evergreen Poltava flora (mesothermal relicts of the Arctic flora of the III period) were identified: Taxus baccata L., Platanus orientalis L., Punica granatum L., Hedera pastuchovii Woronow ex Woronow, Smilax excelsa L. and Diospyros lotus L. With the exception of Smilax excelsa L., other 5 species are listed in the Red Book of the Azerbaijan Republic. In the Zakatala and Belokan districts, relict tree and shrub plants belonging to 15 families, 23 genera and 30 species of Arctic and deciduous Turgai flora (mesothermal relicts of the Arctic flora of the III period) are widespread. Of these, 10 species (Pinus kochiana Klotzsch ex K. Koch = Pinus sylvestris var. hamata Steven, Fraxinus coriariifolia Scheele, Castanea sativa Mill., Quercus iberica Steven ex M. Bieb., Pterocarya pterocarpa (Michx.) Kunth ex Iljinsk., Juglans regia L., Acer pseudoplatanus L., Acer hyrcanum Fisch. ex C. A. Mey., Corylus colurna L., Vitis vinifera L., are considered rare plants of Azerbaijan. It was established that 38 rare tree and shrub species belonging to 35 there are 23 families.

Agronomic evaluation and adaptability of Pinot gris to an environment with high grey mould disease pressure: a comparative analysis on 17 clones

The grapevine (Vitis vinifera L.) cultivar Pinot gris is an international variety that has spread world wide and is oneof the most important in Italy, especially in the northern regions where almost half of the world's total is grown. Over a three-year period (2019–2021), a comparative study was conducted on 17 clones to evaluate their agronomic aptitudes, susceptibility of grapes to Botrytis cinerea, fertility of buds, vigour, and oenological characteristics. We aimed to provide local viticulture with agronomic, sanitary status, and oenological indications that help to choose the genotype that best fits and enhances the clone/environment synergy. This is important given climate change, one of the most significant factors affecting viticulture. Hence, productive, qualitative, and health surveys were conducted on grapes during harvest. Vigour and vegetative/productive balance were also evaluated regarding the weight of the pruned wood. The Ravaz index and fertility of buds were studied when the inflorescences were separated and clearly visible (between DOY 131 and DOY 141 each year). The confirmation of the bunch was also evaluated (shape and number of wings) according to the Organisation Internationale de la Vigne et du Vin (OIV) descriptors. Through the use of digital photogrammetry, some descriptors of the cluster that most correlate with the severity of Botrytis cinerea were identified. In 2020 and 2021, microvinifications were carried out in white and with maceration of skins, respectively, following tested protocols. Sensory analysis of the wines was performed with a trained panel of experts. The study revealed interesting differences between clones concerning grapes' qualitative, productive, and sanitary aspects. Some clones stood out for their sugar accumulation, yield and resistance to Botrytis cinerea, as well as for the oenological olfactory profile. Statistical analysis highlighted that the severity of Botrytis cinerea and bunch rot was not correlated with the vigour of the plant but rather with the hardness of skin, content of soluble solids, soluble solids/total acidity ratio, pH, and total acidity. From the sensory analysis, several clones had a higher score for some descriptors in both study years and were more appreciated than others.

Genotyping-by-sequencing-based high-resolution mapping reveals a single candidate gene for the grapevine veraison locus Ver1.

Veraison marks the transition from berry growth to berry ripening and is a crucial phenological stage in grapevine (Vitis vinifera): the berries become soft and begin to accumulate sugars, aromatic substances, and, in red cultivars, anthocyanins for pigmentation, while the organic acid levels begin to decrease. These changes determine the potential quality of wine. However, rising global temperatures lead to earlier flowering and ripening, which strongly influence wine quality. Here, we combined genotyping-by-sequencing with a bioinformatics pipeline on ∼150 F1 genotypes derived from a cross between the early ripening variety 'Calardis Musqué' and the late-ripening variety 'Villard Blanc'. Starting from 20,410 haplotype-based markers, we generated a high-density genetic map and performed a quantitative trait locus analysis based on phenotypic datasets evaluated over 20 years. Through locus-specific-marker-enrichment and recombinant screening of ∼1000 additional genotypes, we refined the originally postulated 5 Mb veraison locus, Ver1, on chromosome 16 to only 112 kb, allowing us to pinpoint the ethylene response factor (ERF) VviERF027 (VCost.v3 gene ID: Vitvi16g00942, CRIBIv1 gene ID: VIT_16s0100g00400) as veraison candidate gene. Furthermore, the early veraison allele could be traced back to a clonal 'Pinot' variant first mentioned in the 17th century. 'Pinot Precoce Noir' passed this allele over 'Madeleine Royale' to the maternal grandparent 'Bacchus Weiss' and, ultimately, to the maternal parent 'Calardis Musqué'. Our findings are crucial for ripening time control, thereby improving wine quality, and for breeding grapevines adjusted to climate change scenarios that have a major impact on agro-ecosystems in altering crop plant phenology.

A 4-week Randomized, Double-Blind, Placebo-Controlled Clinical Trial on the Use of Grape Seed Extract for Reducing Plasma Glucose, Lipid Profile, and Blood Pressure in Patients with Type 2 Diabetes Mellitus

: Diabetes mellitus (DM) is a common chronic disease that can significantly decrease life expectancy due to its complications. Grapes (Vitis Vinifera L.) and their byproducts, including seeds, have been used globally to treat various ailments. In this clinical trial, we investigated the effect of Iranian grape seed extract (GSE) on fasting blood sugar (FBS), lipid profile [including total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides (TG)], as well as systolic and diastolic blood pressure (SBP and DBP, respectively) in patients with type 2 DM (T2DM). Seventy-four patients with T2DM were divided into two groups; 38 patients in the treatment group received 263.2 mg of GSE (standardized to contain 250 mg of proanthocyanidine) twice daily, and 36 patients in the placebo group received 263.2 mg of placebo twice daily for thirty days. At the end of the intervention, a statistically significant decrease was observed in SBP [from 125.83 ± 13.39 in the placebo group to 121.94 ± 7.49 in the treatment group (P = 0.002]), and FBS [from 144.75 ± 30.82 in the placebo group to 129.87 ± 31.79 in the treatment group (P = 0.001)]. There were no significant changes in total cholesterol, HDL, LDL, TG, and DBP between the two groups. Consuming Iranian GSE for a short duration can lower FBS and systolic blood pressure (BP), suggesting that GSE may play a key role in improving BP and fasting blood glucose in patients with T2DM.

The Effects of Pigeage, Délestage, Remontage and Oxygenation Treatments Applied during Maceration on Phenolic Content, Aroma Composition and Sensory Properties of Red Teran (Vitis vinifera L.) Wine

The aim of this study was to evaluate the effects of mechanical (pigeage, délestage and remontage) and oxygenation treatments on the phenolic and aromatic compounds and sensory characteristics of Teran wines. The experiment included a 20-day maceration period, during which the above-mentioned treatments were applied, as well as the post-fermentation processes of pressing and first rack. The analysis of phenolic, chromatic and aroma compounds and the sensory characterization of the wines were used to describe the effects of the treatments investigated. After the observed maceration period, remontage resulted in wines with the highest total phenols (2682.0 ± 14.8 mg GAE/L). In contrast, délestage resulted in the lowest total phenols (2499.1 ± 17.6 mg GAE/L) and total anthocyanins (530.1 ± 2.8 mg/L) and had the strongest effects on chromatic characteristics. The post-fermentation processes (pressing, racking) showed similar trends and resulted in higher phenolic concentrations in the remontage wine, while the délestage was again characterized by lower total phenol and anthocyanin concentrations. In addition, the délestage wine contained a higher concentration of almost all analyzed esters and two higher alcohols (2-methylpropan-1-ol and 1-hexanol), while the remontage wine had the highest concentration of 2-phenylethanol and 3-methylbutyl acetate. Finally, maceration proved to be a key factor in defining the wines’ sensory characteristics, with the remontage-treated wine showing the best overall quality.

Effects of Growing Areas, Pruning Wound Protection Products, and Phenological Stage on the Stilbene Composition of Grapevine (Vitis vinifera L.) Canes.

Applying plant protection products (PPP) on grapevine pruning wounds is a viticultural practice used to mitigate the spread of grapevine tuck disease, which is posing serious economic losses in the vine-wine industry. However, the impact of PPP on woody tissues remains unclear. Our study, conducted in two European vineyards, investigated the effects of Cuprocol, Tessior, Esquive, and Bentogran on stilbenes, in canes of Cabernet sauvignon and Syrah, at three phenological stages. Main stilbenes, quantified by HPLC-UV-DAD (1260 Agilent Infinity System) and identified by HPLC-ESI/MS (Thermo Scientific LCQ FLEET system), included E-resveratrol, E-ε-viniferin, E-piceatannol, and E-polydatin. Canes exhibited varying proportions of individual stilbenes, reflecting differences based on climatic conditions and phenological phases, rather than on the application of specific PPP. Vines grown in cool-climate conditions exhibited higher levels of E-resveratrol, whereas vines from the Mediterranean climate area exhibited higher levels of E-ε-viniferin. We also observed divergences in the accumulation trend of wood stilbenes throughout the season in canes collected in the two different growing areas.

The Valorization of Spanish Minority Grapevine Varieties—The Volatile Profile of Their Wines as a Characterization Feature

Despite the large number of existing varieties of Vitis vinifera L., only few occupy a large niche in today’s highly globalized wine market. The increasing consumer demand for diversified products, as well as the changing climatic conditions, make establishing a process of varietal diversification essential to achieve both challenges. It is for this reason that the study of minority varieties, which have a higher level of adaptation to each area of origin, is of particular interest. With the main objective of achieving an in-depth knowledge of minority varieties in Spain, the national research project ‘Valorization of Minority Grapevine Varieties for their Potential for Wine Diversification and Resilience to Climate Change’ (MINORVIN), has been proposed. Within this extensive project, the present study describes the aroma profiles of 60 single-variety wines, corresponding with 44 different varieties, with 12 of these varieties being studied at the same time in several Spanish regions. Volatile compounds were determined through three consecutive vintages using gas chromatography-mass spectrometry (GC-MS) and gas chromatography–flame ionization detector (GC-FID). Compounds were grouped into major compounds, including alcohols, C6 compounds, esters, acetates, acids, carbonyl compounds, and other type of compounds, and minor compounds, including lactones, terpenes, and C13-norisoprenoids, according to their concentration in the wines being analyzed. Among this last group of compounds, lactones were quantitatively the most abundant, followed by terpenes. This study reflects that minority variety wines show distinctive aromatic profiles, supporting the importance of valuing and promoting the autochthonous minority grapevine varieties for the Spanish winemaking industry.

Comparative genomic analysis reveals expansion of the DnaJ gene family in Lagerstroemia indica and its members response to salt stress.

DnaJs/Hsp40s/JPDs are obligate co-chaperones of heat shock proteins (Hsp70), performing crucial biological functions within organisms. A comparative genome analysis of four genomes (Vitis vinifera, Eucalyptus grandis, Lagerstroemia indica, and Punica granatum) revealed that the DnaJ gene family in L. indica has undergone expansion, although not to the extent observed in P. granatum. Inter-genome collinearity analysis of four plants indicates that members belonging to Class A and B are more conserved during evolution. In L. indica, the expanded members primarily belong to Class-C. Tissue expression patterns and the biochemical characterization of LiDnaJs further suggested that DnaJs may be involved in numerous biological processes in L. indica. Transcriptome and qPCR analyses of salt stressed leaves identified at least ten LiDnaJs that responded to salt stress. In summary, we have elucidated the expansion mechanism of the LiDnaJs, which is attributed to a recent whole-genome triplication. This research laid the foundation for functional analysis of LiDnaJs and provides gene resources for breeding salt-tolerant varieties of L. indica.

Determination of Flavonoids and Phenolic Acids in the Liver of Wistar Rats after a Dietary Enrichment with Corinthian Currant (Vitis vinifera L., var. Apyrena): A Liquid Chromatography-Tandem Mass Spectrometry Study.

Corinthian currants are dried fruits produced from Vitis vinifera L. var. Apyrena grape. This study investigated the distribution of phenolic compounds in male Wistar rat livers following two distinct Corinthian currant long-term dietary intake protocols (3 and 10% w/w). Method optimization, comparing fresh and lyophilized tissues, achieved satisfactory recoveries (>70%) for most analytes. Enzymatic hydrolysis conditions (37 °C, pH 5.0) minimally affected phenolics, but enzyme addition showed diverse effects. Hydrolyzed lyophilized liver tissue from rats consuming Corinthian currants (3 and 10% w/w) exhibited elevated levels of isorhamnetin (20.62 ± 2.27 ng/g tissue and 33.80 ± 1.38 ng/g tissue, respectively), along with similar effects for kaempferol, quercetin, and chrysin after prolonged Corinthian currant intake. This suggests their presence as phase II metabolites in the fasting-state liver. This study is the first to explore phenolic accumulation in rat liver, simulating real conditions of dried fruit consumption, as seen herein with Corinthian currant.

Bioprotective effects of different Plant Extracts and Essential Oils against Rhizopus stolonifer and Aspergillus niger causing Post Harvest decay in Grapes

The grapes (Vitis vinifera) are one of the largely consumed fruits in the world. Grape production in Pakistan has increased in the recent years. These are mainly consumed fresh or as dried raisins. Grapes are highly perishable, which makes them liable to rot during transport, storage, and marketing. The perishable nature of grapes leads to a considerable amount of post-harvest loss. The production and quality of grapes are adversely affected by several abiotic and biotic factors. Two different cities Pishin (Balochistan) and Faisalabad (Punjab) fruit market and stores were selected to collect rotten grapes. The fungal pathogens isolated were identified as A. niger and R. stolonifers. The pathogenicity of isolated pathogens was assessed at different temperatures (5, 20, and 30 °C) on the Thompson seedless grape variety. Infection and proliferation of fungi were found conducive at 30°C. As antifungal agents, three organic origin oils, neem, cinnamon, and clove oils with levels i.e., 500, 1000, 2000 ppm as well as marigold and neem extracts with diverse concentrations of like 12.5, 25, and 50% were employed. Among these organic compounds, cinnamon and clove oils at 2000 ppm exhibited 6.54% and 15.3% decay against A. niger, respectively. Meanwhile, against R. stolonifer, cinnamon and clove oils at 2000 ppm exhibited 12.22% and 6.74% decay, respectively. This study's findings focus on the effectiveness of both essential oils and plant extract in significantly delaying the decay process caused by fungal pathogens. The present study underscores the protective ability of the plant extracts and natural oils which could be a way forward for eco-safe management of post-harvest diseases of grapes before they reach the market.

Post-veraison sunlight supplementation improved the phenolic profile of Cabernet Gernischt (Vitis vinifera L.) grape and wine in a temperate monsoon climate

The regulation of solar radiation is a pivotal agricultural practice in enhancing the quality of grapes and subsequently, wine. In regions like Yantai, where solar radiation levels are typically low, the accumulation of wine phenolic compounds is negatively impacted. In light of this, our study sought to assess the efficacy of silver reflective mulch (RM) treatment on grape yield, maturity, and phenolic composition. Specifically, we applied RM treatment post-veraison to a Cabernet Gernischt (Vitis vinifera L.) vineyard in the Yantai wine region of China. Our findings indicate a consistent improvement in grape maturity with RM treatment, alongside enhanced accumulation of total phenols (TP), total tannins (TT), and total anthocyanins (TAC) in grape skin. Consequently, this led to elevated levels of phenolic compounds in wines and heightened color intensity. Moreover, tandem mass spectrometry analysis unveiled higher concentrations of key compounds such as petunidin-3-glucoside, malvidin-3-glucoside, procyanidin B1, quercetin-3-glucoside, cis-resveratrol, and piceatannol in the resultant wines. This study underscores the potential of RM treatment to bolster wine phenolics, particularly in regions characterized by a Temperate Monsoon Climate.

Mining, screening, and validation of cold-resistance molecular markers in Vitis vinifera L.

Mining, screening, and validation of cold-resistance molecular markers in Vitis vinifera L.

Impact of exogenous melatonin foliar application on physiology and fruit quality of wine grapes (Vitis vinifera) under salt stress.

Soil salinisation is an important abiotic stress faced in grape cultivating, leading to weakened plant vigour and reduced fruit quality. Melatonin as a novel hormone has shown positive exogenous application value. Therefore, this study used wine grape (Vitis vinifera ) 'Pinot Noir' as a test material to investigate the changes of foliar spraying with different concentrations of melatonin on the physiology and fruit quality of wine grapes in a field under simulated salt stress (200mmolL-1 NaCl). The results showed that foliar spraying of melatonin significantly increased the intercellular CO2 concentration, maximum photochemical quantum yield of PSII, relative chlorophyll and ascorbic acid content of the leaves, as well as the single spike weight, 100-grain weight, transverse and longitudinal diameters, malic acid, α-amino nitrogen and ammonia content of fruits, and decreased the initial fluorescence value of leaves, ascorbate peroxidase activity, glutathione content, fruit transverse to longitudinal ratio and tartaric acid content of plants under salt stress. Results of the comprehensive evaluation of the affiliation function indicated that 100μmolL-1 melatonin treatment had the best effect on reducing salt stress in grapes. In summary, melatonin application could enhance the salt tolerance of grapes by improving the photosynthetic capacity of grape plants under salt stress and promoting fruit development and quality formation, and these results provide new insights into the involvement of melatonin in the improvement of salt tolerance in crop, as well as some theoretical basis for the development and industrialisation of stress-resistant cultivation techniques for wine grapes.

Ubiquitin ligase VvPUB26 in grapevine promotes proanthocyanidin synthesis and resistance to powdery mildew.

Proanthocyanidins (PAs) are an important group of flavonoids that contribute to astringency, color, and flavor in grape (Vitis vinifera) and wines. They also play a crucial role in enhancing plant resistance to various stresses. However, the underlying regulatory mechanism governing PAs biosynthesis, particularly in relation to conferring resistance to powdery mildew, has not been extensively explored. This study focused on identifying a key player in PAs biosynthesis, namely the plant U-box (PUB) E3 ubiquitin ligase VvPUB26. We discovered that overexpression of VvPUB26 in grape leads to a significant increase in PAs content, whereas interfering with VvPUB26 has the opposite effect. Additionally, our findings demonstrated that overexpression of VvPUB26 in transgenic grapevines enhances defense against powdery mildew, while interfering with VvPUB26 results in increased susceptibility to the pathogen. Interestingly, we observed that VvPUB26 interacts with the WRKY transcription factor VvWRKY24, thereby facilitating ubiquitination and degradation processes. Through RNA-Seq analysis, we found that VvWRKY24 primarily participates in secondary metabolites biosynthesis, metabolic pathways, and plant-pathogen interaction. Notably, VvWRKY24 directly interacts with the promoters of dihydroflavonol-4-reductase (DFR) and leucoanthocyanidin reductase (LAR) to inhibit PAs biosynthesis. Meanwhile, VvWRKY24 also influences the expression of MYB transcription factor genes related to PAs synthesis. In conclusion, our results unveil a regulatory module involving VvPUB26-VvWRKY24-VvDFR/VvLAR that plays a fundamental role in governing PAs biosynthesis in grapevines. These findings enhance our understanding of the relationship between PAs biosynthesis and defense mechanisms against powdery mildew.