Search Results (8)

This study showcases the potential of utilizing LiDAR sensing technologies as an automated, efficient, and rapid method for mapping winter pruning wood across vineyards. It was conducted in 2024 in a commercial vineyard in the region of Attica in Greece in the framework of the “AGROSYS” project. The experimental area was 3.5 ha grown with the Savvatiano variety. Cane weight data were collected manually at pruning, while soil spatial variability and canopy properties were mapped and analyzed. The regression analysis of the three-dimensional point clouds and the manual measurements of pruning weight revealed a strong relationship. This signifies the high potential of accurate mapping of dormant pruning canes across vineyards using rapid and time-efficient digital methods. The analysis also revealed strong relationships with the NDRE and canopy temperature at harvest. Full article

This study investigates the effects of rising temperatures on photosynthetic efficiency and stress tolerance in major Greek grapevine cultivars by using Sauvignon Blanc and Merlot as references. Muscat and Assyrtiko displayed the most heat-tolerant photosynthetic apparatus among the white cultivars, while Mavrodafni was the most heat-tolerant among the red ones, by effectively managing excess light energy. Sauvignon Blanc, although exhibiting heat susceptibility, maintained high photosystem II (PSII) functionality under heat stress by activating photoprotective mechanisms. Savvatiano and Agiorgitiko were more vulnerable to photo-oxidative stress above 35 °C, while Agiorgitiko maintained a functional photosynthetic apparatus, even at 40 °C, by shifting to a more photoprotective strategy. In contrast, Merlot, despite its resistance to photo-oxidative stress, lacked photoprotective investment, resulting in suppressed PSII under heat stress. Moschofilero was the most susceptible cultivar to photo-oxidative stress. Leaf morphological traits also contributed to heat stress tolerance, with smaller, thicker leaves facilitating thermoregulation. The present results provide important insights into specific responses to heat stress of major Greek grapevine cultivars. This knowledge may aid in selecting heat-tolerant genotypes and optimizing vineyard site selection, thereby enhancing the sustainability and climate resilience of viticulture. Full article

This study explores the chemical and sensory differentiation of Greek white wines produced from five indigenous grape varieties—Savvatiano, Vidiano, Moschofilero, Assyrtiko, and Malagouzia—across diverse terroirs in Greece. A targeted analytical approach was employed to quantify 12 key volatile aroma compounds derived primarily from amino acid metabolism and lipid degradation, using GC-MS and GC-FID. The selected volatiles, including isoamyl alcohol, phenylethyl alcohol, tyrosol, and hexanoic acid ethyl ester, were chosen for their sensory relevance and their biosynthetic linkage to nitrogenous precursors. Principal Component Analysis (PCA) of wines from the 2019 and 2020 vintages revealed clear varietal clustering, under standardized winemaking conditions. Malagouzia wines were characterized by rich and diverse volatile profiles, particularly long-chain fatty acids and esters, while Vidiano exhibited a consistently restrained aromatic expression. Sensory analysis using sorting and ultra-flash profiling confirmed the chemical clustering, with Moschofilero, Vidiano and Malagouzia wines forming distinct sensory groups. The findings demonstrate that key amino acid-derived volatiles can serve as biochemical markers of varietal typicity and support the use of volatile profiling as a tool for terroir-driven wine classification and quality assessment in Greek white wines. Full article

This study investigates the impact of climate change on key physiological parameters of Greek indigenous grapevine cultivars (Savvatiano, Muscat, Assyrtiko, Mavrodafni, Moschofilero, and Agiorgitiko), using Sauvignon blanc and Merlot as benchmarks. The aim was to identify genotypes with higher photosynthetic dynamics and water use efficiency (WUE) under heat stress and to examine the role of CO₂ enrichment in modulating these responses. Gas exchange measurements showed that short-term exposure to elevated CO₂ (e[CO₂]) (i.e., 700 ppm) enhanced photosynthesis by 37–64%, 77–89%, and 18–68% under control, moderate, and severe heat-stress regimes (23, 35, and 40 °C), respectively. CO₂ enrichment also improved WUE by 61–122%, 96–138%, and 11–63%, with the greatest benefits at 30–33 °C, depending on genotype. Cultivars with strong CO₂-saturated photosynthetic capacity and small stomata, such as Sauvignon blanc and Mavrodafni, showed greater photosynthetic stimulation and WUE improvement from CO₂ elevation. Stomatal traits influenced photosynthesis under ambient CO₂ (a[CO₂]) but not under e[CO₂]. Of the white varieties examined, Sauvignon blanc and Savvatiano showed the best performance under combined e[CO₂] and heat stress, while Assyrtiko and Muscat adapted better to high temperatures at a[CO₂]. Among red cultivars, Mavrodafni showed the highest photosynthetic efficiency at both CO₂ conditions, even under heat stress. The present findings indicate that grapevine varieties exhibit differential responses to elevated temperature and CO₂ levels. A comprehensive understanding of grapevine responses to stress conditions is therefore essential for the selection of cultivars with enhanced adaptation to climate change. Full article

Grape berries are one of the most important sources of phenolic compounds, either consumed fresh or as wine. A pioneer practice aiming to enrich grape phenolic content has been developed based on the application of biostimulants such as agrochemicals initially designed to induce resistance against plant pathogens. A field experiment was conducted in two growing seasons (2019–2020) to investigate the effect of benzothiadiazole on polyphenol biosynthesis during grape ripening in Mouhtaro (red-colored) and Savvatiano (white-colored) varieties. Grapevines were treated at the stage of veraison with 0.3 mM and 0.6 mM benzothiadiazole. The phenolic content of grapes, as well as the expression level of genes involved in the phenylpropanoid pathway were evaluated and showed an induction of genes specifically engaged in anthocyanins and stilbenoids biosynthesis. Experimental wines deriving from benzothiadiazole-treated grapes exhibited increased amounts of phenolic compounds in both varietal wines, as well as an enhancement in anthocyanin content of Mouhtaro wines. Taken together, benzothiadiazole can be utilized to induce the biosynthesis of secondary metabolites with oenological interest and to improve the quality characteristics of grapes produced under organic conditions. Full article

During the last decade, several studies demonstrated the effect of biostimulants on the transcriptional and metabolic profile of grape berries, suggesting their application as a useful viticultural practice to improve grape and wine quality. Herein, we investigated the impact of two biostimulants—abscisic acid (0.04% w/v and 0.08% w/v) and chitosan (0.3% w/v and 0.6% w/v)—on the polyphenol metabolism of the Greek grapevine cultivar, Savvatiano, in order to determine the impact of biostimulants’ application in the concentration of phenolic compounds. The applications were performed at the veraison stage and the impact on yield, berry quality traits, metabolome and gene expression was examined at three phenological stages (veraison, middle veraison and harvest) during the 2019 and 2020 vintages. Results showed that anthocyanins increased during veraison after treatment with chitosan and abscisic acid. Additionally, stilbenoids were recorded in higher amount following the chitosan and abscisic acid treatments at harvest. Both of the abscisic acid and chitosan applications induced the expression of genes involved in stilbenoids and anthocyanin biosynthesis and resulted in increased accumulation, regardless of the vintage. Alterations in other phenylpropanoid gene expression profiles and phenolic compound concentrations were observed as well. Nevertheless, they were mostly restricted to the first vintage. Therefore, the application of abscisic acid and chitosan on the Greek cultivar Savvatiano showed promising results to induce stilbenoid metabolism and potentially increase grape defense and quality traits. Full article

Nitrogen nutrition is one of the most effective cultural practices in vineyards. The vine nitrogen status influences the berries’ quality characteristics and the produced wines. The current study investigated the effect of traditional nitrogen fertilization in the form of ammonium sulfate compared to nitrogen fertilization coupled with the nitrification inhibitor 3,4-Dimethylpyrazole phosphate (DMPP) on the agronomic characteristics of grapes and the produced wines of the white variety Savvatiano from a productive vineyard in the Attiki region. Must and wine quality was evaluated by a chemical analysis and sensorial evaluation by trained panelists. The different forms of nitrogen fertilizers did not significantly affect the aroma and sensory profile in contrast to unfertilized grapevines. In addition, the applied fertilization increased some important aroma compounds in the wine, compared to no fertilization. The significance of this work is to add information about the effect of nitrogen fertilization on the wine volatile composition of the Greek white grapevine Savvatiano. Full article

The objective of this study was to explore the use of non-Saccharomyces yeasts, individually or in mixed culture, with Saccharomyces cerevisiae for the vinification of must originating from the native white wine grape cultivar Savvatiano (Vitis vinifera L.). Savvatiano is the most planted grape cultivar in Greece, cultivated predominantly in Central Greece. Grapes were harvested during October 2020, were pressed, and the must after cold settlement was inoculated with a. Saccharomyces cerevisiae, b. Metschnikowia pulcherrima, and c. mixed culture, in sequential inoculation (M. pulcherrima, followed by S. cerevisiae after 7 days). The progress of fermentations was monitored and the finished wines were analyzed for the main wine parameters, as well as sensory attributes by a panel of experts. The results of this study provide useful data in order to further explore the effect of mixed culture use on fermentation of musts originating from native grape varieties with low aromatic intensity. Full article