Search results for "Grape"
showing 10 items of 291 documents
Changes in the Phytoalexin Content of Various Vitis Spp. in Response to Ultraviolet C Elicitation
1999
The phytoalexin production potential of three American Vitis species and that of three cultivars of Vitis vinifera were evaluated in response to UV-C irradiation. Time course changes in resveratrol, piceid, epsilon-viniferin, and pterostilbene contents were studied within 3 days after a short UV-C irradiation. Results show that the two major stilbenes accumulated as a response to UV-C elicitation are resveratrol and epsilon-viniferin, a resveratrol dehydrodimer, the concentration of both compounds usually reaching quantities >100 microgram/g of fresh weight. In contrast, piceid and pterostilbene were constantly produced in low quantities. Owing to the results obtained, the role of stilbene …
Soil erosion assessment on tillage and alternative soil managements in a Sicilian vineyard
2011
Mediterranean crops favour high erosion rates. Vineyards use to reach the highest soil and water losses due to the lack of vegetation cover. A topographical approach by means of the use of vineyards poles as fixed reference point as erosion markers allowed to quantify high and non-sustainable soil erosion rates on the Sicilian vineyards during 9 years. In order to develop strategies to control the soil losses, seven land management were selected and applied in a typical blanc wine grape vineyard located in southwestern Sicily. Comparable plots were managed traditionally using conventional tillage and alternatively using various cover crops: 1) Vicia faba; 2) Vicia faba and Vicia sativa; 3) …
Analyses spectrale et texturale de données haute résolution pour la détection automatique des maladies de la vigne
2019
‘Flavescence dorée’ is a contagious and incurable disease present on the vine leaves. The DAMAV project (Automatic detection of Vine Diseases) aims to develop a solution for automated detection of vine diseases using a micro-drone. The goal is to offer a turnkey solution for wine growers. This tool will allow the search for potential foci, and then more generally any type of detectable vine disease on the foliage. To enable this diagnosis, the foliage is proposed to be studied using a dedicated high-resolution multispectral camera.The objective of this PhD-thesis in the context of DAMAV is to participate in the design and implementation of a Multi-Spectral (MS) image acquisition system and …
Nitrogen Distribution in Annual Growth of ‘Italia’ Table Grape Vines
2018
Little information is available about either nitrogen (N) content/concentration in table grape vines. The knowledge about N accumulated by the vine organs during the season could support sustainable fertilization programs for table grape vineyards. The aim of the present paper was to investigate the N content in different annual organs, in summer and winter pruning materials, clusters at harvest and fallen leaves at post-harvest of table grape vines in order to verify the vine annual N requirements to be used for sustainable N fertilization schedules. Biomass and nitrogen were analyzed at six phenological growth stages (flowering, berry-set, berry growth, veraison, ripening, and harvest) fr…
The effect of climate on Burgundy vintage quality rankings.
2019
Aim: Based on consensus rankings from prominent rating authorities, we examined the importance of a suite of climatic variables, organized by winegrape phenological stage, in distinguishing between high- and low-ranked vintages in Burgundy.Methods and Results: Vintage ratings of Burgundy wines acquired from 12 sources were evaluated to develop consensus rankings for red and white wines from 1961–2015. Climate variables (air temperature, precipitation, degree-day accumulations, etc.) were organized by mean phenological stage and compared between good and poor vintages using Mann-Whitney U tests and multivariate stepwise discriminant function analysis. High temperatures, particularly during t…
Purification and structural characterisation of lipid transfer protein from red wine and grapes
2012
Lipid transfer proteins (LTP) play a major role in plant defence and are of particular interest due to their known ability to cause allergic reactions. These proteins are expressed in grapes and also remain detectable after vinification, especially in red wine. However, it remains unknown whether the protein undergoes any changes during the vinification process. Here, we present a purification method for LTPs from Dornfelder grapes and wine. By liquid-chromatography-mass spectroscopy (LC-MS/MS) we identified LTPs from two different species (Vitis vinifera and Vitis aestivalis). Additionally, the purified LTPs were characterised using spectrometric methods, confirming their high purity and s…
Effects of different yeast strains, nutrients and glutathione-rich inactivated yeast addition on the aroma characteristics of Catarratto wines
2021
Catarratto is one of the most common non-aromatic white grape varieties cultivated in Sicily (Southern Italy). In order to improve the aromatic expression of Catarratto wines a trial was undertaken to investigate the effect of yeast strain, nutrition and reduced glutathione. Variables included two Saccharomyces cerevisiae strains, an oenological strain (GR1) and one isolated from honey by-products (SPF52), three different nutrition regimes (Stimula Sauvignon Blanc™ (SS), Stimula Chardonnay™ (SC) and classic nutrition practice), and a specific inactivated yeast rich in reduced glutathione to prevent oxidative processes [Glutastar™ (GIY)] ensuing in ten treatments (T1-T10). Microbiological an…
The cost advantage of Sicilian wine farms
2013
This study presents the results of research carried out on a Sicilian wine farm in order to demonstrat e the economic convenience of the mechanized harvest. After the determination of the minimum optimal farm size that justifies the introduction of grape harve ster in the farm, it has been estimated production cost and the relative profitability of two wine grape cultiv ars (Chardonnay and Nero d’Avola), comparing three hypotheses of harvest: manual, with farm property g rape harvester and with rented grape harvester. The economic analysis shows that the introduction of th e grape harvester in the wine farm is justified in large sized farms. However, even in small farms the use o f rented g…
Implementation of green harvesting in the Sicilian wine industry: Effects on the cooperative system
2015
This paper contributes to assessing the effectiveness of the GH measure to contribute in reducing the supply of wine grapes, and thus contrasting the fall of wine prices in those years when especially abundant productions are expected. By analysing the application of this measure to the Sicilian wine sector during the three-year period (2010–2012), we assess its effects on the regional wine cooperative system. The results from the analysis of the statistical data show that the GH measure was successful in terms of the number of applications, the supported area and financial expenditures, and contributed with other factors to determining a reduction in wine grape production. The empirical su…
Evolution of anthocyanin profile from grape to wine
2010
<p style="text-align: justify;"><strong>Aims</strong>: This study aimed at acquiring knowledge of the evolution of anthocyanins from grape to wine and the possibility of deducing the varietal origin of a wine from its anthocyanin profile.</p><p style="text-align: justify;"><strong>Methods and results</strong>: The anthocyanin « fingerprint », or profile, of a series of autochthonous Sicilian accessions and their respective young wines was determined by HPLC-DAD in 2008. Data were evaluated by taking into account the evolution of the percentages of side-ring dioxygenated and tri-oxygenated anthocyanins, the ratio between acetylated and p-coumaroylate…