Isolation and conservation of plant-associated microorganisms in pure cultures is important to be able to understand their influence on plant health. However, capturing the whole range of microbial taxa detected by culture-independent approaches remains labour-intensive and challenging since a large proportion fail to grow under laboratory conditions. Culturomic approaches that involve using a variety of culture conditions coupled with high-throughput identification methods are a recommended strategy to effectively capture plant-associated microbial diversity. A number of studies have demonstrated that using plant-based culture media rather than conventional laboratory media is an efficient strategy for increasing the cultivability of plant-associated microorganisms. This study aimed to develop a culturomic approach to build a collection of grapevine foliar microorganisms with potential applications for the biocontrol of foliar diseases. We developed and tested a custom grapevine leaf-based culture medium (GLA) to better mimic the leaf habitat and consequently try to increase the cultivability of foliar microorganisms. Of the 90 genera that were isolated, 17 were isolated exclusively on GLA including 4 bacteria, 1 yeast, and 12 filamentous fungi. Overall, using the GLA allowed for the isolation of a number of taxa that are of interest for their biocontrol potential against plant pathogens. Interestingly, it was also effective for isolating and speeding up the growth of slow-growing filamentous fungi associated with grapevine trunk diseases. Using a combination of laboratory media and the custom GLA resulted in a collection that was representative of 12.5 % of bacterial genera and 17.6 % of fungal genera detected on grapevine leaves. This collection will serve as a repository of pure cultures for conducting experiments. Candidates will be screened and tested both individually and in consortia for potential applications in microbial biocontrol against grapevine diseases, particularly Plasmopara viticola (grapevine downy mildew), with the ultimate goal of developing effective biocontrol products and moving towards more sustainable viticulture.

Drought poses a significant challenge to grapevine (Vitis vinifera L.) development, impacting both physiological processes and yield. This study explores the transcriptomic responses of developing buds of cv. Merlot grapevine to drought, focusing on key genetic and physiological adaptations. Grapevines were subjected to a controlled water deficit during critical phenological stages, especially for floral induction, and the transcriptomic analysis revealed complex adaptive mechanisms at the molecular level. Water stress notably affected the grapevine’s growth and caused significant leaf necrosis. Bud fertility measurements in the following year showed a differential impact of drought according to node position along the shoot, with basal (nodes 1–3) and distal buds (nodes 8–10) more affected than the central ones. This caused a decrease in the number and weight of grape inflorescences, particularly at basal nodes. Transcriptomic data from nodes 2, 5, and 10 showed significant changes in gene expression, dealing with stress responses, hormonal signalling, and metabolic processes. Notably, upregulation of genes related to calcium signalling, ROS (Reactive Oxygen Species) detoxification, and cell wall modification was observed, which are crucial for maintaining cellular integrity under stress conditions. Differential expression of genes regulating flowering further highlighted the impact of drought on reproductive development. Post-stress recovery analyses showed a partial reversal of stress-induced transcriptomic changes, with significant upregulation of genes involved in photosynthesis and lipid metabolism, suggesting a complex recovery mechanism. These findings may contribute to a deeper understanding of the physiological and molecular basis of drought tolerance in grapevine, providing insights into strategies for improving grapevine resilience in the face of increasing water scarcity due to climate change.

Microbial interactions play a decisive role in fermentation dynamics and final wine quality. The sequential co-inoculation of non-conventional yeasts with Saccharomyces cerevisiae has been proposed as a strategy to enhance organoleptic properties, reduce ethanol content and/or exert biocontrol over spoilage yeasts, thereby decreasing the use of sulphur dioxide (SO2). Among these species, Wickerhamomyces anomalus has shown effectiveness; however, its interaction with S. cerevisiae under sequential inoculation schemes has not been explored from an ecological modelling perspective. In this study, the population dynamics of both species were analysed using an Ordinary Differential Equation (ODE)-based model, evaluating the influence of co-inoculation timing, temperature, and SO2 concentration to maximise the viability of the biocontrol yeast without affecting the fermentative kinetics of S. cerevisiae. Fifteen fermentations were carried out following a Box–Behnken experimental design, varying temperature (15–20 °C), molecular SO2 (0–0.2 ppm), and co-inoculation time (0–48 h). A Gilpin–Ayala competition model was applied, incorporating secondary temperature models (Arrhenius and Ratkowsky) and constant parameters for the effects of SO2 and co-inoculation time. The model was refined through parameter estimation and the Akaike Information Criterion (AIC), and was experimentally validated under different inoculum proportions. The iterative fitting process led to a simplified Lotka–Volterra model modified solely to include the effect of co-inoculation time. Inoculating S. cerevisiae 48 h after W. anomalus significantly increased the viability of the latter (by 75 % compared to simultaneous inoculation) without affecting fermentative kinetics. Simulations confirmed the final dominance of S. cerevisiae and the convergence of both populations toward the same sink point. Delaying S. cerevisiae inoculation favoured the early establishment of W. anomalus, enhancing biocontrol efficacy without compromising alcoholic fermentation. This simplified ecological model provides a framework to optimise microbial management in winemaking, reduce SO2 usage, and promote more sustainable fermentation processes.

This study presents an improved loop-mediated isothermal amplification (LAMP) procedure for the quick, inexpensive, and precise identification and quantification of lactic acid bacteria (LAB) in white and red wines and in grape musts. Custom primers targeting the 16S rRNA gene were developed to enhance specificity. Key advancements include a mobile phone-based semi-quantification approach using hydroxy naphthol blue (HNB), endpoint quantification using a microplate reader, and a real-time quantitative LAMP (qLAMP) assay using EvaGreen®. Moreover, PMA-qLAMP was optimised to differentiate viable from non-viable bacterial cells. A major advantage arises from the fact that all red and white wine and must samples examined exhibited consistent behaviours. The LAMP improvements described provide wineries with accessible tools for microbial quality control by themselves, offering a practical alternative to traditional methods requiring sophisticated instrumentation.

Argentine Patagonia, recognised as the southernmost wine-producing region in the world, frequently experiences moderate to strong winds. Wind is a key environmental factor that affects plant growth, development, and fruit yield. This study investigates how two contrasting wind conditions (exposed and sheltered) influence the xylem structure of Vitis vinifera L. cultivars Malbec (Mb) and Cabernet-Sauvignon (CS) throughout the lifespan of the vines (2011–2021). We hypothesised that wind exposure modulates xylem structure and hydraulic performance differently depending on the cultivar, based on differences in phenotypic plasticity. During the 2021 dormant season, wood cores were extracted from the main trunk of vines growing under wind exposure and sheltered sectors of the vineyard plot. The differential wind conditions were given by a poplar windbreak. The analysis focused on the response to wind intensity through different anatomical variables, including basal area increment (BAI), cumulative BAI, vessel lumen fraction (F), and vessel area relative to ring area. Climatic data were integrated to explore correlations with xylem modifications. Results showed that CS vines under wind sheltered conditions had significantly greater mean vessel area, indicating enhanced growth and potential hydraulic efficiency, whereas CS vines under wind exposure exhibited vessels with smaller diameter and higher vessel density, maintaining F values while reducing wood productivity. This pattern suggests a structural trade-off between anatomical traits such as vessel size and vessel density, which are typically associated with hydraulic efficiency and resistance to cavitation, rather than a direct assessment of hydraulic safety margin. Results also showed that Mb vines had no significant differences in radial growth but increased vessel size and F under wind conditions, reflecting a more stable and plastic hydraulic strategy. The correlations with seasonal climatic variables revealed a spatial dichotomy: while wind exposure directly shaped anatomy in wind-exposed vines (reducing vessel size, increasing density), temperature was the dominant driver influencing xylem traits in sheltered conditions. These findings provide new evidence of cultivar-specific xylem responses to wind and highlight the importance of considering the phenotypic plasticity in vineyard management. Tailored strategies may enhance vine performance and resilience in windy environments.

The concentration of dissolved oxygen in wine is a critical parameter that must be controlled during the winemaking process to preserve quality post-packaging. However, oxygen uptake occurs at multiple stages, including production, stabilisation, and packaging. Conventional oxygen removal methods, such as boiling at atmospheric pressure and membrane contactors, are either detrimental to wine quality or cost-prohibitive. Consequently, sparging with an inert gas using a bubble column or an in-line sparger remains the primary approach for oxygen removal. While previous research has focused mainly on oxygen absorption, insights into desorption can be obtained from studies on gas–liquid mass transfer in wine and model solutions. Oxygen desorption is quantified by the volumetric mass transfer coefficient (𝑘𝐿𝑎), which is influenced by factors such as viscosity, dissolved carbon dioxide, concentrations of ethanol, phenolic compounds (mainly in red wines), acids, and surfactants. Herein, we provide a comprehensive analysis of how variations in these parameters affect 𝑘𝐿𝑎. Additionally, the effects of hydrodynamics, design parameters, and operating conditions on 𝑘𝐿𝑎 are investigated and presented in this comprehensive review.

Accurate yield estimation is crucial for optimising vineyard management and logistical organisation. Traditional methods relying on manual and destructive flower or berry counts are labour-intensive and unsuitable for large-scale applications. To address these limitations, this study evaluated the potential of RGB image analysis for non-destructive estimation of flower number in grapevine inflorescences and its relationship with yield components. The objectives were: (i) to correlate the number of actual flowers with the number of pixels in inflorescence images, considering the projected area and not visible flower count; (ii) to assess the model’s ability for predicting yield components (number of berries and bunch weight) on the plant scale. The study was conducted during the 2023 vintage in a cv. Catarratto/1103P vineyard located in Sicily, on 36 vines. The vines were trained on a vertical shoot positioning trellis system with a bilateral spur pruned cordon. All the inflorescence images were acquired using a smartphone and white cardboard under field conditions. Images were analysed using FIJI/ImageJ© software, inflorescences were segmented via Otsu’s method, and pixel counts were used to estimate flower number through linear regression. Flower counts were validated through manual counts of detached calyptra. Vines were harvested to measure bunch weight, and the number of berries was counted to calculate the fruit set rate. External model validation was performed on datasets from Catarratto, Chardonnay, and Vermentino cvs. Results showed a strong correlation between inflorescence pixel count and flower number, both on single inflorescences (R2 = 0.78; MAPE 29 %; n = 300) and in terms of total flowers per vine (R2 = 0.95; MAPE 12 %), with estimation accuracy slightly varying according to inflorescence length. External validation yielded an MAPE of 20 % in Catarratto, 40 % in Chardonnay, and 34 % in Vermentino. The model also reliably predicted the number of berries (R2 = 0.94; MAPE 13 %) and bunch weight (R2 = 0.79; MAPE 20 %) per vine. While environmental factors such as fruit set can affect yield, this study highlights the potential for early yield prediction with image analysis. The methodology holds promise for scalable applications and integration into vineyard management technologies in wine and table grapes.

One of the primary challenges of climate change faced by viticulture is the rising frequency of extreme weather events, including heatwaves. The aim of this study was to test apical leaf removal as a mitigation strategy during heatwaves based on the hypothesis that reducing total leaf area translates to lower transpirational water losses, thereby improving the water status of young grapevine plants under multiple stress conditions. Two-year-old Sauvignon blanc vines were subjected to progressive severe drought stress in combination with a heatwave (max air temperature 40 °C), which were simulated in a controlled environment. Key physiological parameters, such as pre-dawn water potential, stomatal conductance, Fv/Fm and net assimilation were measured before (acclimation), during and after (recovery) the heatwave. Drought stressed plants reached a maximum pre-dawn water potential of –1.4 MPa. Drought stress negatively affected all physiological parameters, especially stomatal conductance, which was reduced to almost zero for the duration of the stress. As a consequence, leaf temperatures during the heatwave reached up to 48.8 °C in drought stressed (WS) plants in contrast to well-watered (WW) plants, which reached a recorded maximum of 43.2 °C. Leaf removal had contrasting effects depending on water availability: in WW vines, it reduced cumulative transpiration by 15 %, whereas under drought stress, it had no impact due to near-complete stomatal closure. However, leaf removal positively influenced recovery, since WS leaf removal vines regained stomatal conductance values comparable to WW vines three days after rewatering. By the end of the 5-day recovery period, all physiological parameters in WS plants, whether leaf removal or control, returned to levels comparable to WW vines. Overall, this work proved that the success of apical leaf removal is highly dependent on water stress level. The practical relevance of this research lies in the necessity of finding ways to mitigate the effects of extreme weather events, especially in a context where irrigation water may be not available and with young vines that are characterised by a still undeveloped root system.

Early grape maturation is an important trait for Egypt’s grape export program to meet international market demands on time. A plastic-covering technique along with exogenous brassinosteroids (BR) treatments was used on ‘Flame Seedless’ grapes, in a two-year experiment to assess fruit quality at harvest and during storage. The results indicated that vines protected by plastic cover benefit from early maturation irrespective of BR treatment, with a mean harvest time two weeks earlier than that of grapes grown without the cover. However, this also resulted in a decrease in grape anthocyanin content. The application of BRs could partly compensate for this insufficiency, concurrently enhancing the grapes’ qualitative attributes and storage potential. The upregulation of selected anthocyanin biosynthesis-related genes such as chalcone synthase (CHS), flavanone 3-hydroxylase (F3H), and UDP-glucose-flavonoid 3-O-glucosyltransferase (UFGT)was confirmed to be in a linear and concentration-dependent relationship with BR treatments and associated with significantly increased anthocyanin content. Based on our research, it appears that the combined use of a plastic cover with elevated concentrations of brassinosteroids (0.8 ppm) is a potentially effective strategy for expediting the harvest season and preserving shelf life and the quality of grapes during cold storage.

Over the past 20 years, a number of non-Saccharomyces strains have entered the market, promising various benefits for winemaking. Some strains have been reported to increase the aromatic diversity in wine. In the present study, the non-commercially available strain Starmerella lactis-condensi was tested for this purpose in the production of dry Grüner Veltliner wines. Two experiments were conducted. In the large-scale experiment, 200 L batches of pasteurised Grüner Veltliner must were fermented with St. lactis-condensi, Saccharomyces cerevisiae or both St. lactis-condensi and S. cerevisiae co-inoculation, with three replicates per vintage and variants over two vintages. The wines were characterised analytically, focusing on fermentation and primary aromas, and submitted to sensory analysis. In the small-scale experiment, 34 L of unpasteurised Grüner Veltliner must was compared with unpasteurised Pinot blanc must, using the same fermentation strategy as in the large-scale experiment. These wines were characterised with a focus on fermentation aromas. The results showed that St. lactis-condensi was able to ferment the musts dry, but the finished wines had a lower concentration in thiols, rotundone, some esters and monoterpens and in terms of organoleptic properties, received fewer mentions for aroma descriptors. In comparison, the unpasteurised must fermented with St. lactis-condensi also showed lower concentrations of some free monoterpenes and minor esters but in general, fewer compounds were significantly affected. In contrast to the other aroma groups, it is noteworthy that the mixed varieties showed the highest concentrations of major ethyl esters in both pasteurised and unpasteurised fermentations. Since thiols, rotundone and minor esters are crucial for the aroma profile of Grüner Veltliner wines, the hypothesis that the non-commercial yeast St. lactis-condensi has an advantage over S. cerevisiae in producing particularly aromatic dry white wines can be rejected. Further research is recommended, especially regarding the influence of yeast selection on the rotundone content of Grüner Veltliner, which has been documented for the first time in this study.