-
1دورية أكاديمية
المؤلفون: Thibaut Verdenal, Jorge E. Spangenberg, Vivian Zufferey, Fabrice Lorenzini, Agnes Dienes, Katia Gindro, Jean-Laurent Spring, Olivier Viret
المصدر: OENO One, Vol 50, Iss 1, Pp 23-33 (2016)
مصطلحات موضوعية: grapevine, foliar urea, 15N-labelling, yeast assimilable nitrogen, Agriculture, Botany, QK1-989
الوصف: Aims: Agroscope investigated the impact of the leaf-to-fruit ratio on nitrogen (N) partitioning in grapevine following a foliar urea application with the aim of increasing the yeast assimilable nitrogen (YAN) concentration in the must. Methods and results: Foliar urea was applied to field-grown Vitis vinifera L. cv. Chasselas grapevines as part of a split-plot trial with two variable parameters: canopy height (90 or 150 cm) and fruit load (5 or 10 clusters per vine). Foliar application of 20 kg/ha of 15N-labelled urea (10 atom% 15N) was performed at veraison. The isotope labelling method allowed to observe foliar-N partitioning in the plant at harvest. The leaf-to-fruit ratio varied between 0.4 and 1.6 m2/kg, and strongly impacted the N partitioning in the grapevines. Total N and foliar-N partitioning was mainly affected by the variation of canopy height. The YAN concentration varied from 143 to 230 mg/L (+60 %) depending on the leaf area. An oversized canopy (+31 %DW) induced a decrease in the total N concentration of all organs (-17 %), and a decrease in YAN quantity in the must in particular (-53 %). A negative correlation between the N concentration and the carbon isotope discrimination (CID) could be pointed out in a condition of no water restriction (e.g., R2 = 0.65 in the must). Conclusion: An excessive leaf area can induce YAN deficiency in the must. Thus, a balanced leaf-to-fruit ratio – between 1 and 1.2 m2/kg – should be maintained to guarantee grape maturity, YAN accumulation in the must and N recovery in the reserve organs. Significance and impact of the study: The results of this study encourage further research to understand the role of other physiological parameters that affect N partitioning in the grapevine – YAN accumulation in the must in particular – and add new perspectives for N management practices in the vineyard.
وصف الملف: electronic resource
-
2دورية أكاديمية
المؤلفون: Thibaut Verdenal, Vivian Zufferey, Agnes Dienes-Nagy, Sandrine Belcher, Fabrice Lorenzini, Johannes Rösti, Carole Koestel, Katia Gindro, Jean-Laurent Spring
المصدر: OENO One, Vol 52, Iss 2 (2018)
مصطلحات موضوعية: defoliation, vigour control, yield limitation, wine sensory parameters, Agriculture, Botany, QK1-989
الوصف: Aim: The objective of this work is to investigate the effects of early defoliation on cv. Chasselas under the temperate conditions of Switzerland, with particular attention to berry anatomical traits and wine sensory parameters. Methods and results: Defoliation (removal of 6 basal leaves + 6 lateral shoots per shoot) was completed during three developmental stages of grapevine, i.e., pre-flowering, late flowering and bunch closure, and at two intensity levels. The experimentation was performed repeatedly over four years. In addition to vintage effect, pre-flowering defoliation had a consistent impact on vine agronomic behaviour. The yield was highly affected by the technique (more than 30% loss). Earlier and more intense defoliation had more impact on yield, while post-berry-set defoliation had no effect on yield. Intensive defoliation also modified berry skin thickness and had a positive impact inhibiting Botrytis development. Wine composition and sensory analysis were not affected by the practice. However, pre-floral defoliation affected bud fruitfulness and vigour, i.e., trimming and pruning weights. This result noted a carryover effect that could affect vine sustainability under restrictive conditions. Conclusion: In the context of this study, pre-flowering defoliation seems to be an interesting practice to reduce vigour and control the high production potential of the cv. Chasselas. The intensity of early defoliation allows for the modulation of the impact on the yield in order to prevent excessive yield loss. Significance and impact of the study: Pre-flowering defoliation of the white cultivar represents a prophylactic solution to reduce both chemical entrants and bunch-thinning costs.
وصف الملف: electronic resource
-
3دورية أكاديمية
المؤلفون: Thibaut Verdenal, Vivian ZUFFEREY, Agnes Dienes-Nagy, Katia Gindro, Sandrine Belcher, Fabrice Lorenzini, Johannes Rösti, Carole Koestel, Jean-Laurent Spring, Olivier Viret
المصدر: OENO One, Vol 51, Iss 3 (2017)
مصطلحات موضوعية: defoliation, skin thickness, anthocyanin, glutathione, millerandage, UV, wine sensory parameters, Agriculture, Botany, QK1-989
الوصف: Aim: The objective of this work is to investigate the effects of defoliation on cv. Pinot noir under the mild-climate conditions of Switzerland, with particular attention to berry anatomical traits and wine sensory parameters. Methods and results: Defoliation (removal of 6 basal leaves + 6 lateral shoots per shoot) was completed at three developmental stages of grapevine, i.e., pre-flowering, late flowering and bunch closure. These experimentations were performed repeatedly over six years. In addition to the vintage effect, pre-flowering defoliation had a consistent impact on vine agronomic behaviour. The yield was highly affected by the technique (-30 %). The berry skin thickness doubled, and the polyphenol concentration increased significantly. The free glutathione concentration in the must decreased. Conclusion: Leaf removal at early pre-flowering stage had tremendous consequences on the vine agronomic performance, mainly to the detriment of berry set, thus having a great impact on yield, berry skin thickness, must composition, and wine composition. Significance and impact of the study: Hypothesis about the competition for assimilates between the growing canopy and the inflorescences during the early season was developed. Furthermore, the role of glutathione and anthocyanins – as antioxidants against UV stress – was interpreted, demonstrating that grapevine is able to adapt to abiotic stresses and ensure a sustainable development.
وصف الملف: electronic resource
-
4دورية أكاديمية
المصدر: IVES Technical Reviews (2023)
مصطلحات موضوعية: Agriculture (General), S1-972, Plant culture, SB1-1110
الوصف: Grapevine leaf removal (LR) in the cluster area is a common practice in temperate and cool climates, usually done between berry-set and cluster closure to create a less favourable microclimate for fungal diseases and to improve grape ripening. When applied before flowering, LR affects berry-set and is, therefore, an effective yield-control tool, reducing time-consuming manual cluster thinning; it also improves berry structure and composition (i.e., total soluble sugars [TSS], titratable acidity [TA] and polyphenols) (VanderWeide et al., 2021). The present five-year trial follows a previous study about pre-flowering LR under identical environmental conditions (Verdenal et al., 2019); it validates the sustainability of moderate pre-flowering LR and its possible mechanisation under Swiss climatic conditions, using low-pressure double airflow.
العلاقة: https://ives-technicalreviews.eu/article/view/7834Test; https://doaj.org/toc/2680-4905Test; https://doaj.org/article/ff6e3d3500094579a90e1d668672be6aTest
الإتاحة: https://doi.org/10.20870/IVES-TR.2023.7834Test
https://doaj.org/article/ff6e3d3500094579a90e1d668672be6aTest -
5دورية أكاديمية
المصدر: OENO One, Vol 57, Iss 2 (2023)
مصطلحات موضوعية: grapevine, defoliation, pre-flowering stage, mechanisation, wine quality, GiESCO, Agriculture, Botany, QK1-989
الوصف: The present trial follows a previous study about pre-flowering leaf removal (LR) (Verdenal et al., 2019) and validates the sustainability of mechanical pre-flowering LR under local Swiss vineyard conditions, using a low-pressure double airflow, to reduce the cost of laborious bunch thinning. In previous studies, pre-flowering LR has shown additional benefits over post-berry-set LR in terms of yield regulation and grape and wine compositions. This trial had two objectives: 1) to test the technical feasibility of mechanical pre-flowering LR, using a low-pressure double airflow and 2) to observe the impact of this practice over five years on yield parameters, grape composition at harvest and wine quality over five years. For this purpose, a trial was conducted on the two cultivars, Doral (white) and Gamay (red), to compare four LR treatments, that is, A) mechanical post-berry-set LR, B) manual pre-flowering LR, C) mechanical pre-flowering LR, and D) double mechanical pre-flowering + post-berry-set LR. More broadly, this work provides practical insights into the consequences of pre-flowering LR on the grapevine, pointing out the advantages and the limits of intensity, timing and mechanisation of this practice. In comparison with the mechanical post-berry-set LR, mechanical pre-flowering LR induced a 7 % loss in bud fruitfulness, a 30 % yield loss and a 3 % gain in total soluble solids (TSS) accumulation in grapes in both cultivars, although the improvement in grape maturity was small and uneven through the years; Gamay anthocyanin concentration remained stable. Pre-flowering LR had no overall impact on the quality of Doral and Gamay wines. Damage was observed on the inflorescences due to the intensity of mechanical pre-flowering LR, which resulted in fewer berries per cluster and a lower yield than with manual LR by the same date. A second LR after berry set was also tested to limit the growth of laterals and clean the clusters from the remaining flower caps to prevent the development of fungal diseases, but it did ...
-
6دورية أكاديمية
المؤلفون: Thibaut Verdenal, Ágnes Dienes-Nagy, Vivian Zufferey, Jean-Laurent Spring, Jorge E. Spangenberg, Olivier Viret, Cornelis van Leeuwen
المصدر: OENO One, Vol 56, Iss 2 (2022)
مصطلحات موضوعية: crop regulation, green harvest, nitrogen use efficiency, yeast assimilable nitrogen, aroma, Terclim, Agriculture, Botany, QK1-989
الوصف: Nitrogen (N) is an essential element for vine development and yield; it is also involved in the winemaking process and significantly affects wine composition. It is therefore essential to control and optimise plant N use to ensure an adequate N composition of the grapes at harvest. An improved understanding of the impact of cultivation practices on plant N metabolism would allow a better orientation of technical choices with the objective of quality and sustainability (i.e., fewer inputs, more efficiency). Our trial focused on the impacts of fertilisation and crop thinning on grape N composition. A wide crop load gradient was set up in a homogeneous plot of Chasselas (Vitis vinifera L.) in an experimental vineyard in Switzerland. Foliar urea was applied at veraison in order to compare it with an unfertilised control. Vine development and grape composition were evaluated over two years, with particular attention to the carryover effects of both fertilisation and crop thinning. Foliar N fertilisation effectively increased the amount of N in grapes at harvest in the same year, but had no impact on grape ripeness or carryover effect on year n + 1. Conversely, crop thinning improved grape maturity by reducing fruit N and C demand. Interestingly, amino N proportions could be distinguished according to crop load, while the global grape N concentration at harvest remained unchanged. Some amino acids were more affected by crop thinning than others. The concentrations of alanine, γ-aminobutyric acid (GABA), serine and threonine were reduced by crop thinning. Crop thinning had a strong carryover effect on year n + 1. The carryover impact of crop thinning on grapes in terms of both maturation index and N composition could be observed at the onset of grape ripening on year n + 1. This experiment highlighted the influence of the previous year’s agricultural practices on grape C and N accumulation before and during the ripening phase. Consequently, the modulation of grape composition at harvest should be considered over two ...
العلاقة: https://oeno-one.eu/article/view/5412Test; https://doaj.org/toc/2494-1271Test; https://doaj.org/article/8f53954feb364c5786ffc601695e68fcTest
الإتاحة: https://doi.org/10.20870/oeno-one.2022.56.2.5412Test
https://doaj.org/article/8f53954feb364c5786ffc601695e68fcTest -
7دورية أكاديمية
المؤلفون: Marie Blackford, Montaine Comby, Ágnes Dienes-Nagy, Liming Zeng, Marilyn Cléroux, Fabrice Lorenzini, Gilles Bourdin, Benoit Bach
المصدر: OENO One, Vol 56, Iss 3 (2022)
مصطلحات موضوعية: grape stem extract, polyphenolic compound, anthocyanin, flavan-3-ol, whole bunch fermentation, Agriculture, Botany, QK1-989
الوصف: The removal of stems prior to maceration during red winemaking is generally associated with an improvement in wine quality. However, in recent years, increased interest in the use of stems in winemaking has been observed among winegrowers. Different advantages of this practice have been listed in the literature. In order to better understand their role during winemaking, stems of ten red grape varieties from different winegrowing regions of Switzerland were studied to determine which minerals, acids and polyphenols are extracted under simulated alcoholic fermentation. The composition of the extracts revealed differences between the grape varieties. In addition, the growing conditions and the terroir seem to have an influence on the compounds extracted from the stems, especially the mineral composition such as potassium and copper. Among the extracted polyphenols, phenolic acids and proanthocyanidins were mostly found in the stem extracts, especially caftaric acid, catechin and procyanidin B1. Their concentrations were significant compared to the average values found in wines.
العلاقة: https://oeno-one.eu/article/view/5385Test; https://doaj.org/toc/2494-1271Test; https://doaj.org/article/845fbb4ccd5142828c5bc04b7fe3c61dTest
الإتاحة: https://doi.org/10.20870/oeno-one.2022.56.3.5385Test
https://doaj.org/article/845fbb4ccd5142828c5bc04b7fe3c61dTest -
8دورية أكاديمية
المؤلفون: Marie Blackford, Montaine Comby, Liming Zeng, Ágnes Dienes-Nagy, Gilles Bourdin, Fabrice Lorenzini, Benoit Bach
المصدر: Molecules; Volume 26; Issue 5; Pages: 1240
مصطلحات موضوعية: grape stems, whole clusters, wine, winemaking practice, phenolic compounds, antioxidant activity, maceration technique, polyphenolic compounds
جغرافية الموضوع: agris
الوصف: Often blamed for bringing green aromas and astringency to wines, the use of stems is also empirically known to improve the aromatic complexity and freshness of some wines. Although applied in different wine-growing regions, stems use remains mainly experimental at a cellar level. Few studies have specifically focused on the compounds extracted from stems during fermentation and maceration and their potential impact on the must and wine matrices. We identified current knowledge on stem chemical composition and inventoried the compounds likely to be released during maceration to consider their theoretical impact. In addition, we investigated existing studies that examined the impact of either single stems or whole clusters on the wine quality. Many parameters influence stems’ effect on the wine, especially grape variety, stem state, how stems are incorporated, when they are added, and contact duration. Other rarely considered factors may also have an impact, including vintage and ripening conditions, which could affect the lignification of the stem.
وصف الملف: application/pdf
العلاقة: Analytical Chemistry; https://dx.doi.org/10.3390/molecules26051240Test
-
9دورية أكاديمية
المؤلفون: Thibaut Verdenal, Vivian Zufferey, Mélanie Huberty, Claire Melot, Ágnes Dienes-Nagy, Jean-Laurent Spring
المصدر: IVES Technical Reviews (2021)
مصطلحات موضوعية: Agriculture (General), S1-972, Plant culture, SB1-1110
الوصف: La teneur en azote du moût à la vendange joue un rôle déterminant dans la cinétique de fermentation alcoolique et dans la formation des arômes du vin, particulièrement dans le cas des vins blancs. Au cours des dernières décennies, les pratiques viticoles ont considérablement évolué vers moins d’herbicides et davantage d’enherbement. Dans ce contexte, des carences azotées du moût sont apparues de façon récurrente dans certains vignobles. Comment pouvons-nous adapter nos pratiques culturales à ce contexte de concurrence pour l’azote ?
العلاقة: https://ives-technicalreviews.eu/article/view/4852Test; https://doaj.org/toc/2680-4905Test; https://doaj.org/article/677f9859b11d48818617ba58db3855a3Test
الإتاحة: https://doi.org/10.20870/IVES-TR.2021.4852Test
https://doaj.org/article/677f9859b11d48818617ba58db3855a3Test -
10دورية أكاديمية
المؤلفون: Thibaut Verdenal, Ágnes Dienes-Nagy, Jorge E. Spangenberg, Vivian Zufferey, Jean-Laurent Spring, Olivier Viret, Johanna Marin-Carbonne, Cornelis van Leeuwen
المصدر: OENO One, Vol 55, Iss 1 (2021)
مصطلحات موضوعية: nitrogen use efficiency, agronomical practices, physiology, partitioning, balance, leaf-to-fruit ratio, Agriculture, Botany, QK1-989
الوصف: This review addresses the role of nitrogen (N) in vine balance and grape composition. It offers an integrative approach to managing grapevine N nutrition. Keeping in mind that N excess is just as detrimental to wine quality as N depletion, the control of grapevine N status, and ultimately must N composition, is critical for high-quality grape production. N fertilisation has been intensively used in the past century, despite plants absorbing only 30 to 40 % of applied N. By adapting plant material, soil management and vine balance to environmental conditions, it would be possible for grape growers to improve plant N use efficiency and minimise N input in the vineyard. Vineyard N management is a complex exercise involving a search for a balance between controlling vigour, optimising grape composition, regulating production costs and limiting pollution. The first part of this review describes grapevine N metabolism from root N uptake to vine development and grape ripening, including the formation of grape aroma compounds. The advantages and limits of methods available for measuring plant N status are addressed. The second part focuses on the parameters that influence grapevine N metabolism, distinguishing the impacts of environmental factors from those of vineyard management practices. Areas for further research are also identified.
العلاقة: https://oeno-one.eu/article/view/3866Test; https://doaj.org/toc/2494-1271Test; https://doaj.org/article/4925ef30125345cb915182a4bdc9fe63Test
الإتاحة: https://doi.org/10.20870/oeno-one.2021.55.1.3866Test
https://doaj.org/article/4925ef30125345cb915182a4bdc9fe63Test
