Viticultural Practices Research Articles

Assessing the economic performance of agrivoltaic systems in vineyards – framework development, simulated scenarios and directions for future research

IntroductionThis paper introduces a framework for assessing the economic performance of agrivoltaic systems (AVS) in vineyards. The study aims to classify factors influencing the profitability of integrating photovoltaic (PV) systems with viticultural practices, emphasizing potential synergistic benefits. Focused on the geographic and climatic conditions of Geisenheim, Germany—home to the first AVS installation in viticulture in Germany—the framework highlights the need to explore economic and operational parameters to assess AVS feasibility.MethodsThe study operationalized its framework by simulating various scenarios based on key variables such as capital expenditures (CAPEX), operational expenditures (OPEX), and revenue streams from grape and energy production. Key factors considered included solar radiation, panel transparency, and regulatory impacts. Scenarios evaluated included: i) Configurations with fully opaque and semi-transparent PV modules. Ii) Adjustments for full mechanization of viticulture practices. Iii) Self-consumption of the produced energy. The framework employed these simulations to evaluate economic outcomes and identify profitability determinants under different conditions.ResultsFindings indicate that under current conditions in Germany, AVS systems are not economically viable for widespread adoption. Key results include: Economic Outcomes: High initial costs (CAPEX) and insufficient revenue from combined grape and energy production lead to negative net present values over a 20-year period across all simulated scenarios. Profitability Determinants: CAPEX and energy prices emerged as critical factors, while viticulture-related costs and revenues had a minor impact on overall profitability. Potential Improvements: Scenarios incorporating multiple positive changes—such as premium wine pricing, higher feed-in tariffs, and increased self-consumption of energy—demonstrated potential for economic feasibility.DiscussionThe study underscores that high CAPEX and low revenues from grape and energy production are the main barriers to AVS profitability. For AVS systems to achieve economic sustainability, substantial reductions in installation costs, increases in energy prices, or technological advances in efficiency are required. Promising configurations combining multiple favorable changes suggest a pathway toward economic feasibility but highlight the need for further development and innovation. The framework provides valuable guidance for future research and investment strategies, emphasizing the importance of: i) Long-term Trials: To evaluate viticultural impacts and synergistic benefits. Ii) Dynamic Models: Incorporating evolving revenue streams, cost structures, and regulatory impacts. iii) Broad Assessments: Exploring the environmental and social benefits of AVS alongside economic performance. Continuous updates to the framework will ensure its relevance, reflecting advancements in PV technology, viticultural practices, and policy environments. This approach will help bridge the gap between renewable energy and sustainable agriculture.

Soil-associated fungal and prokaryotic diversity influenced by stoniness, depth and vintage in a high-altitude vineyard

Soil microbes are increasingly recognised as key contributors to wine terroir, playing crucial roles in soil health and nutrient cycling. Fungi and prokaryotes interact with soils, influencing physical and chemical properties and mediating nutrient availability for roots. These microorganisms also impact vine performance and wine quality. Viticulture is expanding to higher elevations due to their cooler temperatures; Mendoza's mountainous regions are of particular interest being, characterised by vineyards with heterogenous soil stoniness. However, the effect of this variability on soil-associated microbial communities remains unclear. This study explores microbial populations (alpha and beta diversity, taxonomical composition, and their relationship with soil physicochemical properties) in soils of contrasting stoniness, at different depths, vintages and sample types. A Malbec vineyard with heterogenous soil stoniness was selected, with two experimental sites 30 m apart containing stony soil (SS; 77 % stoniness) and non-stony soil (NS; 0 % stoniness), respectively, and which were managed identically. Samples were collected from two depths (0.3 m and 0.6 m) during two vintages (2017 and 2018), from bulk and rhizosphere. Amplicon sequencing targeted the V3-V4 region of the 16S rRNA gene (prokaryotes) and the ITS1 region (fungi). Results showed that soil type significantly influences fungal populations, with less effect on prokaryotes. Vintage, reflecting annual changes in weather and viticultural practices, was the most significant factor affecting microbial communities. Depth was particularly important for fungi, while the sampling type (bulk or rhizosphere) had no significant impact on the microbiome within the same soil profile. Certain soil components were found to influence microbial communities: pH affected prokaryotes, while calcareous content specifically influenced the Proteobacteria phylum. Additionally, five fungal orders were more abundant in the stony soils, though some remained unidentified. These findings provide a baseline for understanding microorganisms in contrasting soils types of a high-elevation vineyard, and they highlight the role of microbial diversity in supporting unique soil-plant-environment interactions.

Roots of resilience: Optimizing microbe‐rootstock interactions to enhance vineyard productivity

Societal Impact StatementGrape production relies signifcantly on agrochemicals, such as fertilizers and pesticides, to sustain vine health and yield. However, excessive or improper use of these inputs leads to detrimental environmental effects, including soil degradation, water contamination, and biodiversity decline. To address this, research must explore sustainable alternatives. Enhancing the symbiotic interactions between grapevine rootstocks and beneficial soil microorganisms offers a viable pathway. By fostering these natural relationships, producers and scientists can develop environmentally sustainable viticulture practices that strengthen vine resilience without compromising productivity. This approach also supports the broader transition to regenerative, ecologically balanced agricultural systems.SummaryThe productivity and resilience of vineyards are influenced by complex interactions between grapevine rootstocks and the surrounding soil microbiome. Emerging research has highlighted the pivotal role of these microbe‐rootstock alliances in modulating nutrient acquisition, water‐use efficiency, and pathogen resistance. By leveraging the symbiotic potential of beneficial soil microorganisms, viticulturists can optimize vineyard management practices to enhance overall productivity, stability, and sustainability. Through the strategic selection of rootstocks with enhanced mycorrhizal associations and the targeted introduction of plant growth‐promoting rhizobacteria, growers can support the grapevine in adapting to challenging soil conditions. Aditionally, manipulating the rhizosphere microbiome, through techniques such as biofertilization and reverse microdialysis, can foster the development of robust, disease‐suppressive communities that safeguard the vines against biotic and abiotic stressors. Integrating these microbiome‐centric approaches into comprehensive vineyard management strategies, and potentially in future rootstock genetic improvement programs, holds promise for improving grape yield, quality, and the long‐term resilience of viticultural systems.

Evaluation of three doses of urea applied to leaves, sprayed at pre-veraison and veraison, on Tempranillo must volatile composition over two seasons

The volatile composition of grapes has a direct impact on the final aromatic composition of wine and plays a crucial role in determining its quality. Various factors, such as agronomic practices, climatic conditions or grape variety, can influence the volatile composition of grape juices. This study aimed to determine the influence of three doses of urea, applied at two different phenological stages (pre-veraison and veraison), on the volatile composition of Tempranillo musts, during two consecutive seasons. The urea application did not have an impact on the yield of the vineyard or the general parameters of the Tempranillo must. However, the three different concentrations of urea modified the volatile composition. Specifically, the higher concentration of urea improved the terpenoids, C13 norisoprenoids, and benzenoid compounds in grape juice. Additionally, when urea treatments were applied at pre-veraison, terpenoids, C13 norisoprenoids, esters, and benzenoid compounds were improved in Tempranillo must. However, the weather was an important factor influencing the volatile compounds in Tempranillo musts. Consequently, foliar applications of urea could be an interesting viticulture practice in order to enhance the volatile compounds in Tempranillo musts.

Impact of aeroponic cultivation and plant growth regulators on the biochemical composition of grapevine leaves

Background: Grapevine (Vitis vinifera L.) is a globally important perennial fruit crop, renowned for its economic value and cultural significance. Grape leaves, while often underappreciated, play a vital role in culinary traditions and are valued for their cultural, nutritional, and health benefits. However, the availability of grape leaves is constrained by viticulture practices and chemical treatments that prioritize fruit production over leaf harvesting. This study seeks to compare the biochemical characteristics of grapevine leaves from the cultivar 'Deghin Yerevani' grown from virus-free, tissue-cultured plants under aeroponic and soil conditions within a greenhouse. Objective: To evaluate the impact of aeroponic versus soil-based cultivation and the application of specific growth regulators on the biochemical composition and nutrient content of 'Deghin Yerevani' grapevine leaves, with the goal of optimizing conditions for high-quality leaf production. Materials and Methods: This study, conducted from 2021 to 2023 at the Scientific Center of Agrobiotechnology, ANAU, utilized virus-free in vitro plants of Vitis vinifera L. cv. 'Deghin Yerevani', sourced from the National Grape Field Collection. Plants were cultured in four treatment groups with varying growth media compositions: PGR-free, with Indole-3-acetic acid (IAA), with IAA and Gibberellic acid (GA₃), and with IAA, GA₃, and 6-Benzylaminopurine (BAP). Post-culturing, plants were transferred to either an aeroponic system, which used a misting cycle and maintained controlled environmental conditions, or to a greenhouse with a defined soil mix and monitored moisture levels. Both systems operated for 8 weeks, with each treatment replicated three times. Chlorophylls a and b, ascorbic acid, sugars, and macro- and micronutrient contents were analyzed, and statistical significance was determined using standard error and Student’s t-test (p < 0.05). Results: Grapevine leaves from 'Deghin Yerevani' plants grown in aeroponic systems exhibited significantly higher chlorophyll a, chlorophyll b, and total chlorophyll compared to those grown in soil. Growth regulators, particularly IAA, GA3, and BAP, enhanced chlorophyll content, sugar levels, and Vitamin C across both cultivation methods. Aeroponic systems showed superior results with increased sugar content (5.7 g/100g) and Vitamin C (20.4 mg/100g) compared to soil-based cultivation. Nutrient analysis revealed higher levels of nitrogen, phosphorus, potassium, calcium, and magnesium in aeroponics. Overall, growth regulators and aeroponic cultivation improved the biochemical and nutrient profiles of grapevine leaves. Conclusion: The study demonstrated that aeroponic cultivation and the application of growth regulators significantly enhanced the biochemical composition of grapevine leaves. Higher levels of chlorophyll, sugar, and Vitamin C, along with improved nutrient content, were observed in aeroponic systems compared to soil-based cultivation. These findings underscore the benefits of aeroponics and growth regulators in optimizing grapevine leaf quality, suggesting potential for improved yield and nutritional value in grapevine production. Keywords: 'Deghin Yerevani', grapevine, in vitro propagation, functional foods, Aeroponic Cultivation, Plant Growth Regulators

Enhancing Red Table Grape Coloration Using Tsikoudia: A Novel and Sustainable Approach.

Achieving optimal coloration in red table grapes, especially in warm-climate regions, presents significant challenges due to high temperatures that inhibit anthocyanin biosynthesis. Conventional methods to enhance grape coloration, including the use of abscisic acid (ABA), ethephon, foliar nutrient supplementation, and viticultural practices like cluster trimming and girdling, have limitations related to cost, regulatory restrictions, and potential adverse effects on grapes quality. This study proposes the application of tsikoudia, a traditional Greek alcoholic beverage, as a novel, sustainable, and cost-effective alternative to conventional practices. Tsikoudia, applied during the veraison stage, significantly improved the coloration of 'Crimson Seedless' and 'Red Globe' grapes by enhancing anthocyanin accumulation and altering color parameters. Specifically, lightness (L*), chroma (C*), and hue angle (h), measured using the CIE-Lab color system, were reduced, while the Color Index for Red Grapes (CIRG) was increased. Additionally, total anthocyanin content, determined through spectrophotometric analysis, also showed an increase. These changes indicate a more intense red coloration. This research highlights the effectiveness of tsikoudia in improving grape coloration and contributes to the development of more sustainable viticultural practices.

From vineyard to glass: Measuring consumers’ willingness to pay for innovative rootstock-produced wine through an experimental auction

Availability of new rootstocks in vineyards offers improved sustainability and adaptability to changing climatic conditions. However, the adoption of these innovations in the wine industry can be hindered by consumer perceptions and uncertainty about the intrinsic and extrinsic characteristics of the new rootstock-produced wines. This study aims to address these concerns by examining consumer preferences towards M4 rootstock-produced wines through a consumer test and a willingness-to-pay assessment based on a Becker-DeGroot-Marschak auction analysis. A non-hypothetical experiment design, involving 201 wine consumers from the Veneto and Friuli Venezia Giulia regions of Italy, was employed to identify differences in new patterns of wine consumption due to the information provided. Results show that consumers do not identify noticeable taste differences between wines produced with innovative and traditional rootstocks. However, when informed about the water-saving benefits, their willingness to pay for wines made with the innovative rootstock is 5% higher than for wines using traditional rootstocks. This additional willingness to pay becomes statistically insignificant after tasting the wine. The introduction of the M4 rootstock among vine growers appears to be an effective solution in meeting consumer demand for high-quality products made with environmentally-friendly methods that conserve scarce resources, such as water. The findings of this study contribute to the ongoing debate on the development of sustainable and economically viable viticultural practices that address the challenges posed by climate change.

Foliar applications of phenylalanine and prohexadione calcium for managing tannin content in cold-hardy hybrid grape cultivars

Cold-hardy hybrid grape cultivars have low tannin content compared to Vitis vinifera cultivars, which leads to unbalanced red wines and therefore low-quality wines. Viticultural practices, such as nitrogen fertilisation and the use of plant growth regulators, have shown to be effective interventions to modify tannin content in V. vinifera cultivars and may be effective with cold-hardy hybrids. Foliar applications of phenylalanine (Phe, 100 mg/L) and prohexadione calcium (ProCa, 50 mg/L) were applied separately and in combination (ProCa+Phe) to Marquette grapevines grown in Iowa, USA in 2022 and 2023. Treatments were assigned following a split-plot design. Berry weight, diameter, seeds per berry, tannin content, and iron-reactive phenolics content of skins and seeds were analysed at five phenological time points. Samples from treated vines were compared to untreated control samples using a random-intercepts linear regression model. Overall, the effect of year was more impactful than the individual effects of treatments due to differences in temperature and rainfall during berry development. However, skin and seed tannin and IRP were significantly affected by the Year2023:ProCa interaction at 3 weeks post fruit set and véraison, respectively, suggesting ProCa treatment may be more effective with multiple applications in consecutive years. Low application rate may be a reason for limited treatment effectiveness and further work on dose response may demonstrate foliar sprays of Phe and ProCa to be effective tools at managing phenolics content in Marquette grapes.

Versatile method for grapevine row detection in challenging vineyard terrains using aerial imagery

Accurate detection and differentiation of grapevine canopies from other vegetation, along with individual grapevine row identification, pose significant challenges in precision viticulture (PV), especially within irregularly structured vineyards shaped by natural terrain slopes. This study employs aerial imagery captured by unmanned aerial vehicles (UAVs) and introduces an image processing methodology that relies on the orthorectified raster data obtained through UAVs. The proposed method adopts a data-driven approach that combines visible indices and elevation data to achieve precise grapevine row detection. Thoroughly tested across various vineyard configurations, including irregular and terraced landscapes, the findings underscore the method’s effectiveness in identifying grapevine rows of diverse shapes and configurations. This capability is crucial for accurate vineyard monitoring and management. Furthermore, the method enables clear differentiation between inter-row spaces and grapevine vegetation, representing a fundamental advancement for comprehensive vineyard analysis and PV planning. This study contributes to the field of PV by providing a reliable tool for grapevine row detection and vineyard feature classification. The proposed methodology is applicable to vineyards with varying layouts, offering a versatile solution for enhancing precision viticulture practices.

Aroma Potential of German Riesling Winegrapes during Late-Stage Ripening

The “aromatic maturity” of winegrapes is not fully understood, particularly during the later stages of ripening. The contribution of grapes to wine aroma has historically been challenging to determine, given most aroma compounds originate from nonvolatile precursors. In this study, an analytical approach previously developed for red winegrapes was adapted to assess the “aroma potential” of Riesling from two vineyards in Essenheim and Durbach, Germany, during the 2022 vintage, by extracting and hydrolyzing aroma precursors in an anoxic model wine matrix. Following sensory and chemical analyses of the hydrolysates using flash profiling and gas chromatography, a multiple factor analysis revealed vineyard- and ripening-dependent changes to aroma, even after total soluble solids had plateaued. As samples matured, green apple and fresh/vegetal aromas were prominent among the Durbach hydrolysates, likely due to persistent concentrations of hexanol. Hydrolysates from both vineyards nonetheless developed more pronounced citrus fruit, tropical fruit, and floral aromas, reflecting increased concentrations of various norisoprenoids and terpenoids. Findings suggest delaying harvest past technological maturity could confer greater aromatic intensity and complexity. The analytical approach used here appears promising for future studies on other grape varieties and other factors that could influence aroma, such as viticultural practices and environmental conditions.

Particle film treatments on ‘Assyrtiko’ grapevines enhance physiology and grape attributes in Santorini Island

Like many viticultural regions of the Mediterranean region, Santorini is also affected by climate change. These changing climatic conditions pose challenges to adapt the island’s traditional viticulture practices to the new climatic conditions of climate change, which will intensify in the future, with the use of short- and long-term solutions with a sustainable manner respecting the tradition and the island’s landscape. Viticulture in this region copes with high temperatures, heat waves and drought which affect the maturity process, the technological maturity, as well as the physiology of the grapevine. The aim of this study was to investigate the effects of kaolin and calcium carbonate foliar application on water relations, photosynthesis and berry composition of vines of grape cultivar ‘Assyrtiko’, trained with the traditional training system ‘Kouloura’, under drought conditions and vertical shoot positioned training system in Santorini. The effects of foliar application with kaolin and CaCO3 on vines of grape cultivar ‘Assyrtiko’ were evaluated, focusing on the impact on the vine’s physiology attributes, grape quality, and environmental sustainability. Based on the results of the present study, there were statistically significant differences on vine water stress where the foliar application of inert films reduced water stress during the three studied years. Kaolin and CaCO3 increased significantly the photosynthesis and stomatal conductance of the vines in comparison to the control. Furthermore, the foliar application with inert minerals has reduced sunburn and pest damage. The results of the present study confirm that the application of kaolin and CaCO3 constitutes an effective and economical solution for the water saving of the vines in dry conditions, while at the same time, it can improve the physiology of the plant and preserve the qualitative and quantitative attributes of the grapes. The foliar use of inert particle films on Santorini’s traditional vineyards could consist a sustainable and effective alternative to mitigate the effects of climate change which have intensified over the last decades in the region.

Integrating Spectral Sensing and Systems Biology for Precision Viticulture: Effects of Shade Nets on Grapevine Leaves

This study investigates how grapevines (Vitis vinifera L.) respond to shading induced by artificial nets, focusing on physiological and metabolic changes. Through a multidisciplinary approach, grapevines’ adaptations to shading are presented via biochemical analyses and hyperspectral data that are then combined with systems biology techniques. In the study, conducted in a ‘Moscatel Galego Branco’ vineyard in Portugal’s Douro Wine Region during post-veraison, shading was applied and predawn leaf water potential (Ψpd) was then measured to assess water stress. Biochemical analyses and hyperspectral data were integrated to explore adaptations to shading, revealing higher chlorophyll levels (chlorophyll a-b 117.39% higher) and increased Reactive Oxygen Species (ROS) levels in unshaded vines (52.10% higher). Using a self-learning artificial intelligence algorithm (SL-AI), simulations highlighted ROS’s role in stress response and accurately predicted chlorophyll a (R2: 0.92, MAPE: 24.39%), chlorophyll b (R2: 0.96, MAPE: 17.61%), and ROS levels (R2: 0.76, MAPE: 52.17%). In silico simulations employing flux balance analysis (FBA) elucidated distinct metabolic phenotypes between shaded and unshaded vines across cellular compartments. Integrating these findings provides a systems biology approach for understanding grapevine responses to environmental stressors. The leveraging of advanced omics technologies and precise metabolic models holds immense potential for untangling grapevine metabolism and optimizing viticultural practices for enhanced productivity and quality.

Sustainability in the winemaking industry and the assessment of grape seed characteristics during processing: Evidence from Azerbaijan

In the context of Azerbaijan’s evolving winemaking landscape, this study investigates the sustainability of viticulture with a particular focus on grape seeds, which are crucial for grapevine propagation, oil extraction, and overall vineyard health. The research aimed to examine the morphological, technological, and biochemical characteristics of grape seeds to optimise grape production methods and promote sustainable viticultural practices. To achieve this, seed samples from twelve grape varieties, both local and introduced, were carefully collected and analysed under varying irrigation conditions, including both irrigated and rainfed settings, to allow for a comprehensive assessment. The investigation revealed significant effects of irrigation on seed properties. Specifically, seeds from irrigated grapes were found to be larger, heavier, and richer in oil content compared to those from rainfed grapes. Detailed analyses showed that the nitrogen content of the seeds ranged from 0.96% to 1.46%, cellulose content varied from 18.8% to 25.3%, ash content ranged from 1.9% to 3.1%, nitrogenous compounds fluctuated between 5.5% and 7.2%, and non-nitrogen extractive substances registered between 16.6% and 22.0%. Notably, correlations between seed properties and the efficiency of cold press oil extraction were identified, providing valuable insights. This research ultimately contributes to the advancement of sustainable viticulture practices in Azerbaijan, ensuring the long-term health and productivity of vineyards within the region

Environmental impact assessment of horse and mechanical traction for vineyard cultivation

In the European Union, energy consumption in agriculture and forestry is less intense than in other economic sectors. However, fossil and non-renewable sources, particularly oil, are predominant, with higher percentages than in different economic sectors. In this context, this study aims to compare the environmental impact generated by equine and mechanical traction for viticulture practices in an organic production context, using life cycle assessment (LCA). Three scenarios were considered: business as usual (i.e., tractor-grown grapes) and horse-grown grapes but with two feeding options (tractor-grown hay and horse-grown hay). The results show that the tractor-grown grape scenario has higher impacts in five impact categories whereas the horse-grown scenario shows higher Global Warming, and to a minor extent Land use. Specifically, the worst results of the control scenario are in the mid-point category of Inorganic Respiratory due to fuel use, which produces P M 2.5. Fuel use is also the cause of the highest environmental burdens in other categories such as terrestrial Ecotoxicity. A sensitive analysis of the results was performed considering the endpoint damage categories. The outcomes show that, in general, the impact of horses is quite stable even under potentially different conditions. Some categories (ecosystem quality, global impact) are only slightly affected by variation in growth time, while all other categories (human health, resources, climate change) experience greater variation.

Challenges in viticulture practices in a changing environment: Can green waste amendment benefit soil properties of vineyards in the Mediterranean?

In Southeastern France, viticulture is of great social, cultural, and economic importance. This sector is threatened by climate change particularly in the Mediterranean (longer droughts and more frequent heat waves) where soils are poor in organic matter and weakly developed. Since organic amendment can strongly modify soil properties and consequently the final products (grapes and wine), the effects of sustainable practices on soil characteristics have to be carefully assessed. This seasonal field survey focuses on the effects green waste amendment (GWA), i.e. semi-composted green wastes, have on vineyard soil functionality. The effects of GWA were compared with those of grass cover (GC), known as a sustainable practice. Soils were collected in vineyards under organic practices (Bouches-du-Rhône and Var, France) over four seasons and physico-chemical (Total C and N, pHwater, pHKCL, EC, WHC, copper content and soil organic carbon SOC) and biological (microbial respiration and biomass, microbial catabolic structure, earthworm abundance and biomass) properties were characterized. Both practices were beneficial to soil physicochemical properties. For example, under both practices, higher (2 fold) Total N and SOC on late spring were observed. Both GWA and GC favored soil microbial communities, with microbial respiration having doubled and tripled on late spring. Similar results were observed for microbial biomass and both bacterial and fungal catabolic diversities (increased approximately by half) over summer. These benefits were particularly prominent during drought season (June and August), and probably linked to a shift in microbial communities as revealed by catabolic profiles. GWA also favored abundance and biomass of earthworm during winter. These findings reveal the potential GWA to counteract the effect of tillage, to mitigate the stress from drought and to improve overall soil functionality in vineyards.

Deciphering Terroirs’ Code: Vineyard Site Selection for Phenolic Performance in ‘Kalecik Karası’ Grape Cultivar (V. vinifera L.)

AbstractUnderstanding the complex interplay between environmental factors and grape quality is crucial for the viticulture industry, as it directly influences wine quality and the distinctiveness of products. This significance underpinned our comprehensive study, which aimed to dissect the relationships between ‘terroir’, including the altitude, regional climate, soil characteristics, vineyard management practice, and the composition of grapes in cv. ‘Kalecik Karası’ (Vitis vinifera L.). Six vineyard sites ranging from 115 to 1180 m altitude were studied. Total soluble solids (TSS, °Brix) titratable acidity, pH and color index of red grapes (CIRG) were evaluated as the main maturity indices and phenolic composition based on anthocyanin and tannin was analyzed. According to the results of the study, we deduced the critical importance of adopting region-specific viticultural practices tailored to the unique environmental conditions of each terroir. This approach not only optimizes grape quality but also accentuates the uniqueness of the wines produced, reflecting the inherent qualities of their origin. The highest altitude Nevşehir (1180 m) showed high levels of total and extractable anthocyanin highlighting the region’s favorable conditions for these compounds (355.26 mg kg−1 and 364.00 mg kg−1), while exhibiting the second lowest skin tannin (1979.40 mg kg−1 and 2180.78 mg kg−1) in both years. Particularly for cultivars like ‘Kalecik Karası’, our study demonstrated how specific terroirs could significantly affect their phenolic composition and, consequently, wine quality. By aligning viticultural practices with the distinct characteristics of each terroir, producers can enhance both the quality and distinctiveness of their wines. This emphasizes the necessity of ongoing research and adaptation in viticultural strategies to fully harness the potential of diverse grape varieties and terroirs, ensuring the production of high-quality wines that truly reflect their origin.

Setting the morphologic quality limits enabling accurate classification of charred archaeological grape seeds

This study investigates the morphological changes in grape pips resulting from various charring conditions. Employing high-resolution scanning combined with morphometric measurements for morphological analysis, we aimed to understand the effects of charring on grape pips. Our morphometric analysis demonstrated significant alterations in seed shape above 250 °C. The length–width ratio and the occurrence of cracks notably changed, providing a basis for assessing charring conditions. In addition, applying a machine learning classification method, we determined that accurate classification of grape varieties by the morphometric analysis method is feasible for seeds charred at up to 250 °C and 8 h. Integrating the morphometric changes and temperature ranges suitable for classification, we developed a sorting model for archaeological seeds. By projecting length–width ratios onto a curve calculated from controlled conditions, we estimated charring temperatures. Approximately 50% of archaeological seeds deviated from the model, indicating drastic charring conditions. This sorting model facilitates a stringent selection of seeds fit for classification, enhancing the accuracy of our machine learning-based methodology. In conclusion, combining machine learning with morphometric sorting enables the identification of charred grape seeds suitable for identification by the morphometric method. This comprehensive approach provides a valuable tool for future research for the identification of charred grape seeds found in archaeological contexts, enhancing our understanding of ancient viticulture practices and grape cultivation.

From the vineyard soil to the grape berry surface: Unravelling the dynamics of the microbial terroir

While unique bacterial and fungal communities are identified in various vineyard habitats, including soils, roots, and trunks, the impact of soil microbiota on the structure of communities colonizing the fruit surface remains puzzling. Our focus encompasses three aspects: the influence of soil microbiota on the surface microbiota of berries, the patterns of co-occurrence across different biological kingdoms, and a comparative analysis of the soil microbiota’s impact on both endophytic and epiphytic fungi that colonize grape berries. The Aureobasidium and Alternaria genera dominated mature berries but were noticeably absent or in low abundance in soil, while Basidiomycota featured prominently in both vineyard soils and on grape berries. Comparisons between soil and grape berry microbiota challenged the notion of a direct connection, revealing low overlap. Co-occurrence analysis unveiled habitat-specific networks, emphasizing alternative sources for berry colonization. This echoes earlier reports of limited correlation in microbial communities between soil and grape berries. In this study, we broaden our inquiry by incorporating data from a published study. This enables us to conduct a comparative analysis of the soil fungal metagenome, focusing on the endophytic and epiphytic microbiota associated with grape berries. Regional comparisons demonstrated differences in community diversity and dissimilarity in microbial profiles, emphasize the influence of local conditions, suggesting that the microbial composition of vineyards is shaped by region-specific factors. These findings underscore the multifaceted nature of soil and grape microbiota interactions, offering crucial insights for advancing our comprehension of vineyard ecosystems and informing agricultural and viticultural practices.

Synthetic Aperture Radar in Vineyard Monitoring: Examples, Demonstrations, and Future Perspectives

Synthetic aperture radar (SAR) technology has emerged as a pivotal tool in viticulture, offering unique capabilities for various applications. This study provides a comprehensive overview of the current state-of-the-art applications of SAR in viticulture, highlighting its significance in addressing key challenges and enhancing viticultural practices. The historical evolution and motivations behind SAR technology are also provided, along with a demonstration of its applications within viticulture, showcasing its effectiveness in various aspects of vineyard management, including delineating vineyard boundaries, assessing grapevine health, and optimizing irrigation strategies. Furthermore, future perspectives and trends in SAR applications in viticulture are discussed, including advancements in SAR technology, integration with other remote sensing techniques, and the potential for enhanced data analytics and decision support systems. Through this article, a comprehensive understanding of the role of SAR in viticulture is provided, along with inspiration for future research endeavors in this rapidly evolving field, contributing to the sustainable development and optimization of vineyard management practices.

Bunch thinning and its influence on the shoots growth dynamics in some syrah wine variety clones

During the period 2020-2022, an experiment was conducted in the experimental vineyard of the Agricultural University – Plovdiv, and four clones of the wine variety Syrah, numbered 100, 174, 470 and 524, grafted on the SO4 rootstock were selected as the study object. During the „pea size“ phase, the green pruning operation – bunch thinning was applied. The shoots growth starts from the vegetation phase „first leaf appearance“ and ends at the „veraison“. The average duration is about 100 days, covering the period of May, June and July. It was found that the vine shoots from a clone 470 reached the greatest average length, V3 – 285, 265, 290 cm and V7 – 359, 336, and 380 cm, and those from a clone 100 were distinguished by the weakest growth, V1 – 197, 203 and 205 cm and V5 – 240, 228 and 245 cm. Differences were proven between the variants, both in the non-reduced (V1, V2, V3, and V4) and in those with reduced yields (V5, V6, V7, and V8), as after reducing the number of bunches, the length of the shoots was longer – high in all vines from the used Syrah clones. This study provides information on the relationship between the applied green pruning operation (bunch thinning) during the growing season and its effects on the vegetative growth. Balancing the vines bud load by controlling yield during the growing season is a preferred viticultural practice for increasing the grape quality. Keywords: Clones, Syrah, green pruning, bunch thinning, shoot growth