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BACKGROUND: Genetic breeding is essential to develop grapevine genotypes adapted to warm climates and resistant to pathogens. Traditionally cultivated Vitis vinifera is susceptible to biotic and abiotic stresses. Winemakers and consumers, however, perceive wines from non‐vinifera or hybrid cultivars as inferior. In this study, sensory analyses and comprehensive metabolite profiling by targeted and untargeted approaches were used to investigate the oenological potential of wines from grapes of genotypes developed throughout four breeding cycles to improve climate adaptation, sugar contents and berry color. RESULTS: Novel genotypes had higher yields and the wines exhibited increased contents of polyphenols, including anthocyanins. Volatile monoterpenes in the wines decreased throughout breeding cycles in the absence of selective pressure. Polyphenol contents were higher in intermediate wines, with hydroxytyrosol contents reaching up to three times reported values. Mouthfeel attributes astringency, leafy taste, flavor and body, and persistency showed significant correlation with untargeted features. Supervised model‐based analyses of the metabolome effectively discriminate wines from distinct genetic origins. CONCLUSION: Taken together, the results demonstrate the potential of novel grapevine genotypes to a more sustainable viticulture and quality wine production in warm climates. Comprehensive metabolite profiling of the wines reveals that genotype clustering is dependent on the chemical class and that traits not submitted to selective pressure are also altered by breeding. Supervised multivariate models were effective to predict the genetic origin of the wines based on the metabolic profile, indicating the potential of the technique to identify biomarkers for wines from sustainable genotypes. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Stilbenes, naturally occurring polyphenolic secondary metabolites, play a pivotal role in adaptation of various plant species to biotic and abiotic factors. Recently, increased attention has been directed toward their potential to enhance plant stress tolerance.We evaluated drought tolerance of three grapevine varieties grown with different levels of water deficit. Throughout, we studied physiological mechanisms associated with drought stress tolerance, particularly stilbene accumulation in root tissues, using HPLC. Additionally, we explored the possible relationship between antioxidant potential and stilbene accumulation in response to water deficit.The results underscore the detrimental impact of water deficit on grapevine growth, water status, and membrane stability index, while revealing varying tolerance among the studied genotypes. Notably, Syrah variety had superior drought tolerance, compared to Razegui and Muscat d'Italie grapes. Under severe water deficit, Syrah exhibited a substantial increase in levels of stilbenic compounds, such as t‐resveratrol, t‐piceatannol, t‐ɛ‐viniferin, and t‐piceid, in root tissues compared to other genotypes. This increase was positively correlated with total antioxidant activity (TAA), emphasizing the active role of resveratrol and its derivatives in total antioxidant potential. This demonstratres the potential involvement of resveratrol and its derivatives in enhancing antioxidant status of the drought‐tolerant Syrah grape variety.Our findings suggest that these stilbenes may function as valuable markers in grapevine breeding programs, offering novel insights for the sustainable cultivation of grapevines in water‐limited environments. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Winegrape production is an essential cultural heritage and economic engine of many regions of the world. Regenerative management, which is gaining traction with industry and consumers alike, relies on soil biodiversity for agroecosystem function, reducing external inputs and increasing ecosystem resilience to climate change. We evaluated the effects of no‐till and sheep integration on vineyard soil biodiversity and soil ecosystem function. No‐till had stronger effects on microbial diversity, while sheep grazing stimulated microbial functioning. By providing a better understanding of the practices, we provide fundamental information for growers that want to embrace regenerative principles, ultimately contributing to the sustainability and resilience of the winegrape industry. Summary: Regenerative management aims to optimize soil microbial function and diversity for enhanced agroecosystem functionality. Understanding the effects of management practices on soil microorganisms is crucial in the context of growing societal interest in this type of management.This study evaluated the short‐term effects of two soil conservation practices: sheep grazing and no‐till, on abundance, diversity, activity, and network complexity of prokaryotes and fungi in a vineyard soil. Four treatments were applied for 3 years: (1) grazed and tilled, (2) grazed and non‐tilled, (3) non‐grazed and tilled, and (4) non‐grazed and non‐tilled. We hypothesized that stacking of conservation practices (grazing and no‐till) would increase microbial diversity, function, and network complexity.Grazing had strong effects on microbial function, increasing the α‐glucosidase, β‐glucosidase, cellulase, phosphatase, and β‐xylosidase enzymatic activity by 82%, 48%, 61%, 39%, and 55%, respectively, compared to non‐grazed soils, while not causing significant changes in soil microbial diversity. Tillage had strong effects on soil prokaryotic and fungal diversity. For prokaryotes, significant interactions in alpha diversity were found between tillage and grazing, and between tillage and sampling location (tractor row and under vine). Fungal Shannon diversity index was higher in the subsoil (15–30 cm) while a significant interaction between depth, location, tillage, and grazing was found for the Chao‐1 index. Microbial network properties were only significantly affected by sampling depth.This study shows that the lack of disturbance in non‐tilled and non‐grazed soils resulted in a more diverse soil community, while grazing stimulated microbial function, thus showing a decoupling between diversity and function in vineyard soil ecosystems. [ABSTRACT FROM AUTHOR]

Biological acidification and bioprotection are interesting tools to overcome some problems of climate change and fit some consumer requirements for fresher wine styles. Juices of Airén (Vitis vinifera L.) were fermented by Lachancea thermotolerans (Lt) and Metschnikowia pulcherrima (Mp) starters and compared with Saccharomyces cerevisiae (Sc). Fermentations were monitored and wines were analysed for standard parameters and volatile fractions by SPE-GC–MS. Wines were evaluated by an experienced tasting panel. All ferments reached dryness with lower volatile acidity and lower ethanol than the control. All strains of Lt used for biological acidification reduced the pH values of wines (pH 3.25–3.56) more than chemical acidification with 1.5 g/L of tartaric acid (pH 3.64). Wines were characterised by different total acidity and volatile composition according to the yeasts used. Lt and Mp produced wines with higher perception of freshness and acidity than Sc control, probably elicited by the higher production of lactic acid complemented with higher contents of succinic acid (+0.2–0.6 g/L). Overall, the results showed that bioacidification is a practical alternative to chemical acidification to cope with either climate change or consumer demand for fresher wine styles. • Selected non- Saccharomyces starters have adequate fermentation performance in co-culture with S. cerevisiae. • Simultaneous co-inoculations of Lt and Mp produce a modulation of sensory profile. • Significant pH reduction and better physicochemical stability compared with chemical acidification with tartaric acid. • Bioacidification is an alternative to chemical acidification with tartaric acid and reduces the use of additives (TH 2 & SO 2). • The sensory perception of freshness is increased by bioacidification. [ABSTRACT FROM AUTHOR]

Pesticide residues in grapes are usually transferred into the wine during vinification and thus, contribute to a certain human exposure. The objective of the present study was to explore whether spiked samples could be a suitable alternative to the still mandatory field-treated samples in the processing study set-up. Grapes treated with fluxapyroxad in the vineyard and untreated grapes spiked with fluxapyroxad after harvest were processed into wine to check for differences in residual fluxapyroxad. Additionally, the behavior of 13 further pesticides during winemaking was characterized using spiked samples. Grape, must, pomace, and wine samples were analyzed by LC-MS/MS following a QuEChERS extraction protocol. The transfer of fluxapyroxad into wine from field-treated and spiked samples was found to be similar, with processing factors (PF) of 0.31 and 0.33, respectively. A strong correlation between PF and the octanol-water partition coefficient (logK OW) was identified for 13 of the 14 pesticides present in the spiked samples (R2 = 0.89, p < 0.0001). Determined PF were compared with values from the European database of processing factors for pesticides in food , which originate from field-treated samples. No significant differences were found, indicating that field-treated samples are not an absolute necessity for investigating the transfer of pesticides into wine. • White wines made from field-treated and spiked grapes were compared. • The concentration of pesticide residues is decreasing during winemaking. • Processing factors for white wine ranged from 0.12 to 0.87. • Field-treated samples and spiked samples lead to comparable processing factors. • Processing factors for wine are correlating with the logK OW values of the pesticides. [ABSTRACT FROM AUTHOR]

The coordination between sugar and aroma compounds concentration in grape berries under water stress still unclear. Here, the field grown 'Marselan' (Vitis vinifera L.) vines were submitted to two levels of water stress (T1: −0.40 MPa ≤ Ψ PD < −0.20 MPa; T2: −0.60 MPa ≤ Ψ PD < −0.40 MPa) from 20 to 120 days after anthesis across two consecutive vintages (2021, 2022). The concentration of bound aroma compounds was promoted at ripe stage under T1, with a particularly significant increase in bound higher alcohols. In the PCA analysis, we found that the influences caused by weather conditions between two vintages were larger than those between treatments, the cooler weather promoting the concentration of aroma compounds. According to the OPLS-DA analysis, the concentration of bound benzyl alcohol, 1-heptanol, α -terpineol, 1-octen-3 - ol and 1-hexanol was closely related to that of sugar. Furthermore, T1 promoted the expression of sugar transporters, glycosyl transferase and higher alcohol concentration at the veraison stage; in particular, the expression of VvSUC12 was highly correlated with the concentration of bound alcohols. Taking all findings into consideration, T1 could be more favorable to increase the bound alcohols concentration by upregulating the β -D-glucose transport. [Display omitted] • Mild water stress applied 20 days after anthesis and over enhances the berries quality. • Water stress promotes glucose rapid accumulation at the veraison stage. • Water stress increases the concentration of free lipids and bound higher alcohols. • Changes of sugar concentration are synergistic with bound aroma compounds concentration. • VvSUC12 may involve in promoting the accumulation of bound aroma compounds. [ABSTRACT FROM AUTHOR]

• The organic acids and anthocyanins exhibited a strong vintage effect. • The June and September precipitation had a positive impact on anthocyanin concentrations, the soil total potassium content had a negative impact. • The July to September temperature diurnal range, trellis system, vine perimeter, and canopy height were the main drivers of δ¹³C, which further influences grape anthocyanin concentrations. Terroir leaves its influence on the flavor build-up in grape berries by triggering biochemical reactions that ultimately shape the typicality of the produced wines. However, the complex relationship between terroir, carbon stable isotopic composition, and the biochemical composition of grapes remains poorly understood. To fill these gaps, grape berries were harvested at maturity from two grape cultivars, Cabernet Sauvignon and Merlot (Vitis vinifera L.), across 32 sites within the Eastern Foothills of the Helan Mountains region over two vintages. The climate and soil data for these sites were collected, and cultivation practices were surveyed. In parallel, the grape quality indicators were measured at maturity to explore their variations among sub-regions and the correlations between terroir factors and grape quality. Moreover, the carbon stable isotopes (δ¹³C) were measured to evaluate the water status of vines at different sites. Results indicated that organic acids and anthocyanins exhibited a strong vintage effect, with the cooler vintage exhibiting higher levels of these compounds relative to the warmer vintage. Specifically, the Hongsipu sub-region, with a cooler climate, consistently demonstrated higher anthocyanin concentrations than other sub-regions in both vintages of the study. Further analysis revealed that the cultivar Cabernet Sauvignon displayed a higher ratio of di-hydroxylated to tri-hydroxylated anthocyanins in the cooler year, whereas Merlot exhibited the opposite trend. The Mantel test identified several critical factors influencing anthocyanin concentration, including total soil phosphorus (Tp), total soil potassium (Tk), soil thickness (Thickness), precipitation (April-September precipitation, Pre4–9), April-September average temperature (4–9 Tave), April-September active accumulated temperature (4–9 Aa), April-June active accumulated temperature (4–6 Aa), July-September active accumulated temperature (7–9 Aa), temperature diurnal range (May, July, August, September, DR-5 and DR 7–9), trellis system, vine density, and δ13C. Finally, structural equation modeling (SEM) was used to analyze and summarize the relationships between terroir factors, anthocyanin concentration, and δ¹³C. The results indicated that June and September precipitation had a positive impact on anthocyanin concentrations, while soil total potassium content had a negative impact. On the other hand, the July to September temperature diurnal range, trellis system, vine perimeter, and canopy height were the main drivers of δ¹³C, which further influenced grape anthocyanin concentrations. This research contributes to a scientific foundation for grape cultivation in the Eastern Foothills of the Helan Mountains and provides valuable insights for practices in other regions. [ABSTRACT FROM AUTHOR]

Lignin is a potential source of polyphenols with different biological activities which might be affected by the extraction or isolation process. This study investigated the effect of ozonation on the bioactive properties of water-soluble lignin extracts from Miscanthus giganteus (grass-type biomass) and Vitis vinifera (wood-type biomass). Total polyphenolic content, antioxidant activities (ABTS, DPPH and β-carotene bleaching assays), and antimicrobial properties were evaluated. Although ozonation did not improve the antioxidant activity per gram of lignin extract with any of the methods employed, it significantly enhanced extraction of antioxidants. All lignin extracts displayed significant antioxidant potential, DPPH IC50 values ranging from 7.6 to 29.0 µg/mL and ABTS ranging 64.1–154.6 mg Trolox/g extract. Miscanthus lignin extracts achieved 70.6 % β-carotene bleaching inhibition, compared with 96.2 % inhibition by BHT. Miscanthus lignin extracts exhibited better yield and antioxidant activity compared with vine shoots, likely due to their lower molecular weight and higher content of phenolic monomers. Antibacterial analysis revealed that Miscanthus lignin extracts had superior activity against Staphylococcus aureus and Escherichia coli , which was enhanced by ozonation and linked to zeta potential and compositional aspects. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for Miscanthus extracts were 3 mg/mL and 6 mg/mL, respectively. Miscanthus extracts from 160 min ozonation demonstrated better antifungal activity than vine shoots, particularly against Penicillium digitatum (MIC:12 mg/mL) compared with Botrytis cinerea (MIC:25 mg/mL). The bioactive properties of water-soluble lignin extracts from ozonated Miscanthus open up new possibilities for their potential use in food and food packaging applications. • Ozonated Miscanthus and vine shoots lignin extracts had antioxidant and antimicrobial activity. • Ozonation process increased the extraction of total polyphenols from both biomasses. • Longer ozonation decreased antioxidant activity of lignin extracts. • Longer ozonation increased antimicrobial activity of lignin extracts. • Miscanthus lignin extracts had higher antimicrobial activity than vine shoots. [ABSTRACT FROM AUTHOR]

Stilbenes are specialized metabolites that are particularly abundant in Vitis species. Although the biosynthetic pathways of stilbenes have been well-characterized, the role of specific peroxidases in stilbene oligomerization remains to be investigated. In this study, we used grapevine cell cultures to characterize the functional role of Vitis vinifera peroxidase 4 (VvPRX4) in the production of resveratrol oligomers after elicitation with methyl jasmonate (MeJA). We showed that MeJA triggers the accumulation of t -resveratrol, resveratrol dimers, and predicted resveratrol trimers in culture medium. This accumulation was correlated with upregulation of the PRX4 gene in grapevine cells. Using bacterial crude extracts containing VvPRX4, we demonstrated that VvPRX4 converts t -resveratrol into dimers, t -ε-viniferin into tetramers, and both combined substrates into resveratrol trimers. Additionally, VvPRX4 mediates the formation of glycosylated dimers using t -piceid and t -resveratrol as substrates. These results highlight the functional role of VvPRX4 in stilbene oligomerization in MeJA-elicited grapevine cell cultures.

Herbivorous insects need to cope with changing host plant biochemistry caused by abiotic and biotic impacts, to meet their dietary requirements. Larvae of the multivoltine European grapevine moth Lobesia botrana, one of the main insect pests in viticulture, feed on both flowers and berries. The nutritional value and defence compounds of these organs are changing with plant phenology and are affected by climate change which may accordingly alter plant-insect interactions. Here, we assessed the impacts of future elevated atmospheric CO 2 concentrations on the host plant quality of different grapevine organs and the larval performance and the transcriptome of L. botrana. Using the Geisenheim VineyardFACE facility, where 'Riesling' and 'Cabernet Sauvignon' were cultivated in the field under ambient or elevated (ca. + 20%) atmospheric CO 2 concentrations, we found that nutrient (amino acids and sugars) and defence compound (phenolic compounds) concentrations of inflorescences and ripening berries differed strongly due to plant phenology and less due to cultivar and CO 2 concentration. Assessing global gene expression after feeding on the respective organs, we found that larval transcriptomic plasticity largely mirrored the plant biochemical plasticity. Larval relative growth rate differed between treatments in a plant phenology-dependent manner. Grape berries contained higher amino acid concentrations and altered phenolics profiles after larval feeding. In the near future, the grapevine-L. botrana interaction will probably change less because of elevated CO 2 concentrations than it does currently during one season. Changes associated with plant phenology, however, may be relevant for contemporary pest management., (© 2025 The Author(s). Molecular Ecology published by John Wiley & Sons Ltd.)