Search Results (149)

Background: Biostimulants naturally improve plant growth, stress tolerance, and nutrient use efficiency and activate defenses by increasing protective metabolites (phenols, anthocyanins) in grapes. In viticulture, especially when using inactive yeasts, they modulate genetic expression and improve the skin resistance, color, and aroma profile of wine grapes in line with sustainable practices. Methods: Two wine grape cultivars, Merlot and Cabernet Sauvignon, were sprayed with the inactive yeast Saccharomyces cerevisiae in a single treatment in pre-veraison or in a double treatment in pre-veraison and veraison. Berry weight, must, total polyphenols, anthocyanins, and mechanical and colorimetric properties were measured on fresh grapes. Results: Two-way ANOVA revealed that titratable acidity (TA), pH, and total polyphenol content (TPC) were not affected, while mean berry weight and anthocyanin content varied by cultivar, treatment, and interaction; total soluble solids (TSS) differed only by cultivar. Inactive yeasts reduced weight in the single-treatment thesis but stabilized it in the double-treatment one; anthocyanins decreased in Cabernet Sauvignon but increased in Merlot. Mechanical and colorimetric analyses showed cultivar-dependent responses, with significant improvements in elasticity, skin thickness, and hue of berries, especially in Merlot when the treatment was applied twice. Conclusions: Inactive yeasts (IYs) showed an effect on the weight of the berries, the anthocyanins, the mechanics, and the color; Merlot significantly improved skin thickness, elasticity, and hue; and Cabernet remained less reactive to treatments. Full article

Water status is a key determinant of physiological performance and vineyard productivity. However, its assessment through field measurements is time-consuming and labour-intensive. Remote sensing offers a fast and reliable alternative to traditional in situ methods for the monitoring of the water status in vineyards. This study aimed to assess the potential of high-resolution multispectral imagery acquired by UAVs to estimate the vine water status. The research was conducted over two growing seasons (2021 and 2022) in a commercial Merlot vineyard in Yepes (Toledo, Central Spain), under five irrigation regimes designed to generate a range of water statuses. UAV flights were performed at two times of day (09:00 and 12:00 solar time), coinciding with in-field measurements of physiological parameters. Stem water potential (SWP), chlorophyll content, and photosynthesis data were collected. The SWP consistently showed the strongest and most stable associations with vegetation indices (VIs) and the red spectral band at 12:00. A simple linear regression model using the NDVI explained up to 58% of the SWP variability regardless of the time of day or year. Multiple linear regression models incorporating the red and NIR bands yielded even higher predictive power (R² = 0.62). Stronger correlations were observed at 12:00, especially when combining data from both years, highlighting the importance of midday measurements in capturing water stress effects. These findings demonstrate the potential of UAV-based multispectral imagery as a non-destructive and scalable tool for the monitoring of the vine water status under field conditions. Full article

The bacterial microbial community composition during wine fermentation is a key contributor to wine quality and flavor. However, studies on the regulatory effects of different grape varieties and co-fermentation processes on the microbial community structure and their synergistic mechanisms remain limited. In this study, Cabernet Sauvignon (CS) was subjected to single-variety fermentation and used as the base wine for co-fermentation with three other grape varieties—Marselan (CSMN), Merlot (CSMT), and Cabernet Gernischt (CSCG)—to systematically compare the differences in the microbial community composition and their effects on the production of metabolic compounds. The results showed that, compared with single-variety fermentation, co-fermentation significantly increased the α-diversity of microbial communities (the Shannon index increased) and exhibited significant differences in β-diversity (PERMANOVA analysis, R² = 0.421, p < 0.001). A neutral model analysis indicated that co-fermentation had a significant impact on microbial community assembly mechanisms, with the contribution of neutral processes to community assembly increasing from 45.5% (in the CSCG process) to 62.3% (in the CSMT process). A microbial co-occurrence network analysis revealed that co-fermentation enhanced the network complexity of microbial communities and strengthened the synergistic interactions between microbial taxa. A metabolic compound analysis revealed that co-fermentation significantly enhanced the production of key aroma compounds, resulting in increased concentrations of isoamyl acetate, ethyl hexanoate, linalool, and geraniol. These findings highlight the differences in microbial communities and their synergistic mechanisms among co-fermented grape varieties, providing theoretical guidance and practical insights for optimizing co-fermentation processes and improving wine quality. Full article

The production of winter wines in Southeastern Brazil represents a relatively recent but expanding viticultural approach, with increasing adoption across diverse wine-growing regions. This system relies on the double-pruning technique, which allows for the harvest of grapes during the dry and cooler winter season, favoring a greater accumulation of sugars, acids, and phenolic compounds. This study aimed to characterize the phenological stages, thermal requirements, yield, and fruit quality of the fine wine grape cultivars ‘Sauvignon Blanc’, ‘Merlot’, ‘Tannat’, ‘Pinot Noir’, ‘Malbec’, and ‘Cabernet Sauvignon’ under double-pruning management in a subtropical climate. The vineyard was established in 2020, and two production cycles were evaluated (2022/2023 and 2023/2024). Significant differences in the duration of phenological stages were observed among cultivars, ranging from 146 to 172 days from pruning to harvest. The accumulated thermal demand was higher in the first cycle, with a mean of 1476.9 growing degree days (GDD) across cultivars. The results demonstrate the potential of Vitis vinifera L. cultivars managed with double pruning for high-quality wine production under subtropical conditions, supporting the viability of expanding viticulture in the state of São Paulo. ‘Cabernet Sauvignon’ and ‘Sauvignon Blanc’ showed the highest yields, reaching 3.03 and 2.75 kg per plant, respectively, with productivity values of up to 10.8 t ha⁻¹. ‘Tannat’ stood out for its high sugar accumulation (23.4 °Brix), while ‘Merlot’ exhibited the highest phenolic (234.9 mg 100 g⁻¹) and flavonoid (15.3 mg 100 g⁻¹) contents. These results highlight the enological potential of the evaluated cultivars and confirm the efficiency of the double-pruning system in improving grape composition and wine quality in non-traditional viticultural regions. Full article

Wine DNA fingerprinting (WDF), retrieved from the amplification of a wider panel of Simple Sequence Repeat (SSR) marker mappings in the Vitis vinifera L. genome, was used to assess the monovarietal nature of Brunello di Montalcino wine. The reliability of the varietal assessment was carried out by estimating the PI values associated with resolutive unrooted dendrograms depicting the correct varietal nature of different wines. As few as five SSR DNA markers associated with a PI value of one over a million or less, PI ≤ 10⁻⁶, can identify the purity of Sangiovese against Merlot, Pinot Noir, Cabernet Sauvignon, Primitivo (Zinfandel), and genetic variants of the Sangiovese as plant references. WDF was used on other monovarietal wines obtained from Cabernet Sauvignon, Merlot, Chardonnay, and Pinot Noir to test the feasibility of the method. In blended wines, the test was able to trace the main varietal component in a three-variety blend, keeping the varietal fingerprint detectable when the main variety was at least 75% (v/v). The data confirm how local genetic variants of Sangiovese can be tracked in commercial wines, becoming, at wine makers’ demand, part of an evidence synthesis of geographical origin. Full article

The assessment of the ovarian reserve is important in patients with fertility intent. The anti-Müllerian hormone (AMH) serum level is a useful ovarian reserve marker. Endometriosis is a benign disease with three phenotypes: superficial peritoneal endometriosis (SUP), ovarian endometrioma (OMA), and deep endometriosis (DE). Endometriosis is linked with infertility; however, the exact impact of endometriosis and endometriosis surgery on AMH levels is less clear. This narrative review examines how different endometriosis phenotypes and related surgeries affect AMH levels as well as explores whether pre- and post-surgical AMH can predict the reproductive outcomes in women seeking pregnancy. The evidence suggests that OMA is linked to reduced AMH values and a higher AMH decline rate over time. OMA cystectomy causes further a reduction in AMH, which, however, tends to recover postoperatively. Non-excisional surgery for OMA spares the ovarian parenchyma; however, an at least temporary decline in AMH is observed. The effect is likely smaller than that of cystectomy. Non-thermal methods of hemostasis following cystectomy are likely superior in terms of AMH. The AMH levels before OMA cystectomy appear to be positively correlated with the postoperative probability of pregnancy, particularly spontaneous conception, but not livebirth rates. Preoperative AMH levels are also predictive of the risk of diminished ovarian reserve (DOR). Similarly, postoperative AMH levels and the rate of AMH decline at 1 year after OMA cystectomy appear to be predictive of fertility outcomes. SUP likely has little (if any) impact on AMH levels. DE reduces AMH levels, and a further reduction following surgery is anticipated. However, a reduction in AMH values should not be interpreted as a decline in the patient’s reproductive potential. Further research should focus on the extra-ovarian locations of endometriosis and their impact on AMH values. Full article

Semi-arid viticultural regions globally are experiencing severe and frequent growing-season heat waves that negatively impact grapevine (Vitis vinifera L.) physiological performance and productivity. At the leaf level, heat stress can photodamage both Photosystem I (PSI) and Photosystem II (PSII). In order to study the self-protection mechanism of grapevine leaves, in this study, 3-year-old potted ‘Merlot’ and ‘Muscat Hamburg’ grapevines were exposed to a 5-day simulated heatwave (45/25 °C day/night) and compared to vines maintained at 25/18 °C. After heat exposure, ‘Merlot’ demonstrated superior thermotolerance and superior physiological performance as measured by gas exchange, oxidative parameters, chlorophyll loss, and photoinhibition of PSI and PSII. Additionally, non-photochemical quenching (NPQ) dissipated the excess light energy in the form of heat. Y(NPQ) progressively rose from 0 to 0.6, signaling the start of the grapevine leaves’ self-defense against temperature stress. Furthermore, the stimulation of cyclic electron flow (CEF) under high temperatures contributed to the energy balance of PSI. The CEF of ‘Muscat Hamburg’ under high light intensities increased dramatically from 1 to 4. NAD(P)H dehydrogenase-dependent CEF around PSI increased markedly, suggesting its role in self-protection. These results demonstrate that both NPQ and CEF play key photoprotective roles by generating a proton gradient under heat stress. Full article

The objective of this work was to investigate the effect of location on the composition and quality of wines from the viticultural zone PGI Drama. Grapes from two white (Sauvignon blanc, Assyrtiko) and three red varieties (Merlot, Cabernet Sauvignon, Agiorgitiko) were collected from nine locations within the zone during 2022. The vineyards span distances ranging from several hundred meters to 100 km, and their altitudes vary from 90 to nearly 820 m. Vinification was performed following the same protocol according to the type of wine. Wines were analyzed for quality parameters such as pH, total acidity, alcohol, and residual sugar content. In addition, elemental composition, phenolic content, antioxidant capacity, and sensory attributes of the wines were assessed. The obtained results suggested that besides the type of wine and variety, the location significantly affects the quality parameters of the wine. PCA analysis revealed that location is an important factor affecting the wine quality. The areas north and northwest proved more suitable for specific varieties, as they produce wines with more distinct organoleptic characteristics. The results provide insights into the behavior of international and native varieties in the face of global warming and assist in decisions concerning the most suitable plant material. Full article

Non-Saccharomyces yeasts have the potential to ameliorate wine ethanol levels, but such fit-for-purpose yeast strains are still lacking. Seventy-one indigenous non-Saccharomyces yeasts isolated from spontaneous fermentations of four wine regions in China (Ningxia, Xinjiang, Gansu, and Shaanxi) were screened for ethanol formation and were characterized for major metabolite profiles in synthetic grape juice fermentation to obtain non-Saccharomyces yeasts with low ethanol yields. Four Hanseniaspora strains with less volatile acidity production were primarily selected, and their ethanol yield was reduced by 22–32% compared to S. cerevisiae. These strains were further evaluated for oenological properties, namely ethanol and temperature tolerance, H₂S production, and killer activities against S. cerevisiae. Strain HuC-3-2 was then subjected to Atmospheric Room Temperature Plasma (ARTP) mutagenesis, and a mutant (HuC32-2-72) with rapid growth and optimized ethanol-reducing capability was obtained. The best-performing strains were further characterized in sequential fermentations with S. cerevisiae in Merlot juice, and resulted in a 1.4% v/v decrease in ethanol yield. Comprehensive analysis of yeast populations and the production of key metabolites highlighted important carbon sinks, as well as glycerol formation, partially accounting for the ethanol reduction. In addition to ethanol amelioration, the Hanseniaspora strains also led to alterations in many metabolites, including volatile compounds and some organic acids, which can further modulate wine aroma and flavor. Full article

Grapes are one of the widely cultivated fruits, with high nutritional value and economic value. The widespread occurrence of grape virus diseases has seriously affected the development of the grape industry. The grapevine varieties “Merlot”, “Cabernet Sauvignon”, “Syrah”, “Chardonnay”, “Welsch Riesling ”, and “Riesling Weiss” were used as materials for screening grapevines carrying the viroid GYSVd1 by RT-PCR. Principal component analysis (PCA) was employed to systematically assess the physicochemical indexes of both grape berries and wine in order to determine the extent of the influence of GYSVd1 on the quality of grape berries and wine. The results demonstrated that GYSVd1 infection significantly compromised both berries and wine quality across the tested cultivars, albeit with distinct varietal susceptibility patterns. Regarding berries’ quality, the negative impact of GYSVd1 followed this decreasing order: Merlot > Chardonnay > Welsch Riesling > Syrah > Riesling Weiss > Cabernet Sauvignon. Similarly, for wine quality, the negative impact exhibited the following gradient: Welsch Riesling > Riesling Weiss > Chardonnay > Cabernet Sauvignon > Syrah > Merlot. There were significant differences in the amount of sugar, acid and phenolic substances between GYSVd1-infected and -uninfected grapevines, but no significant differences in berry weight, berry shape index, and alcohol content. GYSVd1 affected the quality of berries and wine mainly by regulating the contents of sugar, acid, and phenolic substances. Full article

The influence of the vineyard location, the yield per vine and the type of alcoholic fermentation on the composition of Merlot wine from two consecutive vintages was investigated in a simultaneous experiment. Grapes from two locations and two crop loads per vine, from controlled and thinned vines, were vinified. At the same time, grapes from control vines were vinified with inoculated and spontaneous alcoholic fermentation. Comparisons of the wine composition were made using a targeted metabolomic approach, microbiological analysis and sensory evaluation. It has been confirmed that the composition of Merlot wine is essentially determined by the location of the vineyard. The analytical marker used to distinguish the two locations was the content of 3-mercaptohexan-1-ol (significantly higher in location B with 38–130%). It has also been shown that the type of alcoholic fermentation has a greater influence on the composition of the wine than the crop load. The analytical marker used for the cluster thinning was the pH of the wine, which increased significantly by 0.03 to 0.08 units with the lower crop load, and for the type of alcoholic fermentation, the concentration of 2-phenethyl acetate, which relates to the sum of acetates and 2-phenylethanol, which increased significantly by 58–299%, 54–218%, and 24–46% in the spontaneously fermented wines. Both the location of the vineyard and spontaneous alcoholic fermentation influenced the significant differences in the sensory characteristics of the wine, while cluster thinning had no such influence. The other influences of the two technical factors on the wine composition depended on the location of the vineyard and the vintage. It can also be concluded that spontaneous alcoholic fermentation reduced the influence of the vintage on the wine composition, while the opposite was the case with cluster thinning. Full article

Drama represents one of the distinct winegrape regions in the continuous growth of northern Greece. Yet, little is known about grape, must, and wine quality in various parts of the region. Determining the physicochemical characteristics of the Merlot, Cabernet Sauvignon, and Agiorgitiko grape varieties grown in different locations in the area across two vintages, their chromatic characteristics, phenolic profile, and organoleptic characteristics were the goal of this study. The results reveal a high variation in the physicochemical characteristics of must and wine among the locations. The location affects the profile of phenolic compounds with procyanidin B2, catechin, procyanidin B3, procyanidin B1, epicatechin, and gallic acid being present in high amounts. Merlot wines from the location with the highest altitude showed a higher amount of quantified phenolics. Altitude positively affected the yeast assimilable nitrogen (YAN) levels and negatively the wine’s purple hue. Moreover, the grape weight negatively affects the levels of some of the quantified phenolic compounds. On the other hand, both altitude and YAN positively impact the taste of wines. The altitude represents a significant parameter in the location studied that influences the quality parameters and taste of the wines. As part of climate adaptation strategies for viticulture in the Drama region and other comparable regions, high-altitude vineyard development should be studied to preserve the grape’s acidity and counteract warming trends. Full article

The chemical profiles of young and mature wines produced from three grape varieties Merlot, Mavrud, and Sauvignon blanc were analyzed using ¹H nuclear magnetic resonance (NMR) spectroscopy and advanced statistical methods. Furthermore, grape ales―a hybrid of beer and wine—were subjected to analysis to facilitate a comparison of their composition with that of traditional wines. The analysis yielded a total of 37 compounds, which were identified and quantified. Orthogonal partial least squares discriminant analysis (OPLS-DA) models were employed to distinguish the chemical profiles of young and mature wines, as well as those of grape ales. The findings demonstrate that the fermentation and aging processes result in the formation of distinctive chemical signatures in wines, with key compounds such as shikimic acid and fructose contributing to this differentiation. The identified compounds comprise seven alcohols (2,3-butanediol, glycerol, 2-methylpropan-1-ol, 3-methyl-butan-1-ol, myo-inositol, 1-propanol, 2-phenylethanol), six organic acids (galacturonic, citric, lactic, malic, shikimic, succinic), three amino acids (alanine, proline, tyrosine), four sugars (arabinose, fructose, galactose, glucose), coutaric acid, and acetoin. The levels of these 22 components enabled the successful differentiation of young and mature wines among the three grape varieties. These findings underscore the substantial chemical distinctions between grape ales and wines, thereby emphasizing the potential of grape ales as an innovative fermented beverage. Full article

Wine color and mouthfeel are essential organoleptic characteristics considered by consumers. In this paper, the potential impacts on color and mouthfeel characteristics in wine, without pomace or prolonged pomace contact after different microwave treatment times, were investigated during storage. The results indicated that the trend changes in color and mouthfeel related parameters (including visible spectrum, brightness, red hue, yellow hue, color difference, saturation, hue angle, total polyphenol content, total monomer anthocyanins, total tannins, total flavan-3-ols, epigallocatechin, catechin, epicatechin, epicatechin gallate, and fluorescence spectrum) after microwave-treated and natural aged wines without pomace and prolong pomace contact were very similar. Moreover, changes in these organoleptic parameters of microwave-treated wine were faster than those of untreated wine, which required a long aging time in traditional processing. Also, microwave treatment had a long-term influence on color and mouthfeel characteristics. All these results showed that prolonged pomace contact technology could obviously improve the clarity and yellowness of wine, and microwave technology could reduce wine aging and rapidly change its color and mouthfeel characteristics. In summary, prolonged pomace contact technology is an interesting strategy to replace traditional fining agents. Microwave technology, as an efficient artificial aging technology, might reduce aging time and rapidly change organoleptic characteristics for producing high quality wine. Full article

Botryosphaeria dieback disease is a significant grapevine trunk disease (GTD) caused by species of Botryosphaeriaceae in Chile and worldwide. Moreover, Botryosphaeriaceae have been described attacking fruit and nut crops in Chile. However, it remains unknown whether fungal isolates from tree hosts have the potential to infect grapevines in Chile. The aggressiveness and potential cross infection of species of Botryosphaeriaceae collected from crops (grapevines, apples, blueberries, and walnuts), was assessed on grapevines. Plant materials, including nursery cuttings, lignified canes, and green shoots of grapevine cultivars (Cabernet Sauvignon, Syrah, Sauvignon Blanc, Malbec, Aspirant Bouschet, and Merlot), were inoculated with Diplodia mutila, D. seriata, Dothiorella sarmentorum, Lasiodiplodia theobromae, Neofusicoccum arbuti, and N. parvum, under greenhouse and vineyard conditions. Regardless of the origin of the isolates, most species of Botryosphaeriaceae were pathogenic on plant materials, causing necrotic lesions of mean lengths from 11.9 to 86.2 mm using mycelial suspension and from 24.8 to 253.7 mm with mycelial plugs. Notably, Neofusicoccum species were the most aggressive, regardless of host origin. Other less aggressive species included L. theobromae, D. mutila, and D. seriata isolated from apple and walnut. This study highlights the potential of species of Botryosphaeriaceae from alternative fruit hosts as inoculum sources for grapevines in Chile. Full article