995 resultados para Vitis labrusca L.


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Este trabalho teve como objetivo desenvolver uma metodologia para a propagação vegetativa do porta-enxerto de videira '43-43'. Estacas lenhosas retiradas em agosto, herbáceas retiradas em janeiro e semilenhosas retiradas em março foram imersas, por 10 segundos, em soluções contendo diferentes doses dos fitorreguladores paclobutrazol (0; 100 e 200 mg.L-1) e ácido indolilbutírico (0; 500 e 1.000 mg.L-1), combinados ou não, totalizando nove tratamentos para cada tipo de estaca. Após 60 dias do plantio das estacas, foram avaliadas as variáveis porcentagem de estacas enraizadas, número de raízes, massa fresca de raízes e porcentagem de estacas com brotações. Estacas lenhosas apresentaram 100% de brotação das gemas, mas não foi constatado enraizamento, independentemente da utilização de reguladores vegetais. Estacas herbáceas que não foram tratadas com reguladores vegetais apresentaram 92,0% de enraizamento e 84,0% de brotação. Para este tipo de estaca, o AIB a 1.000 mg.L-1 aumentou o número de raízes. Estacas semilenhosas apresentaram a maior porcentagem de enraizamento (23,5%) quando se utilizou AIB a 1.000 mg.L-1. Este tratamento também propiciou maior massa e número de raízes; no entanto, estes valores foram inferiores àqueles verificados para estacas herbáceas.

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Este trabalho teve como objetivo avaliar diferentes concentrações de ácido indolbutírico (AIB) no enraizamento de estacas semilenhosas do porta-enxerto de videira 'VR043-43' (Vitis vinifera x Vitis rotundifolia). O experimento foi realizado na Universidade Federal do Paraná, Curitiba-PR, no período de dezembro de 2004 a janeiro de 2005. As concentrações de AIB testadas foram 0; 1.000; 2.000 e 3.000 mg L-1, sendo a base das estacas imersas nas soluções dos reguladores vegetais, durante dez segundos. Após 40 dias em câmara de nebulização, as estacas foram avaliadas. As estacas com maior porcentagem de enraizamento foram aquelas que não receberam tratamento com AIB (92,5%). A porcentagem de estacas mortas aumentou com as concentrações de AIB, e a porcentagem de retenção foliar diminuiu. Houve incremento do número médio de raízes primárias por estacas com as maiores concentrações de AIB, porém as matérias fresca e seca das raízes não diferiram significativamente entre os tratamentos. Conclui-se que o AIB não é necessário para o enraizamento de estacas semilenhosas do porta-enxerto 'VR043-43'.

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Diferentes sistemas solventes foram aplicados para determinar a eficiência de extração de compostos com capacidade antioxidante em bagaço de uva, importante subproduto do processo de vinificação. Realizou-se a quantificação de compostos fenólicos totais, antocianinas totais e atividade antioxidante nos extratos de bagaço de uva Vitis vinifera das variedades Tannat e Ancelota, provenientes da região de Videira, Santa Catarina. A atividade antioxidante foi determinada pelos métodos ABTS, FRAP e β-caroteno/ácido linolico. Conteúdos de compostos fenólicos totais em acetona 50 e 70% foram maiores nas duas variedades, enquanto que os conteúdos de antocianinas totais extraídos em ambas as variedades foram maiores no solvente etanol em concentrações de 50 e 70%. Pelo método ABTS, a atividade antioxidante foi maior nas concentrações de 50 e 70% de acetona para a variedade Tannat e 50 e 70% de acetona e etanol para a variedade Ancelota. Em relação ao poder redutor pelo método FRAP, este foi maior em solvente acetona 70% para as duas variedades. No ensaio do poder de inibição da oxidação, a adição de 100 e 200 µL de extratos etanólicos a 50% das variedades Tannat e Ancelota apresentou maior eficiência, sendo quase duas vezes superior aos extratos acetônicos testados.

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Niagara Peninsula of Ontario is the largest viticultural area in Canada. Although it is considered to be a cool and wet region, in the last decade many water stress events occurred during the growing seasons with negative effects on grape and wine quality. This study was initiated to understand and develop the best strategies for water management in vineyards and those that might contribute to grape maturity advancement. The irrigation trials investigated the impact of time of initiation (fruit set, lag phase and veraison), water replacement level based on theoretical loss through crop evapotranspiration (ETc; 100,50 and 25%) and different irrigation strategies [partial root zone drying (PRD) versus regulated deficit irrigation (RD!)] on grape composition and wine sensory profiles. The irrigation experiments were conducted in a commercial vineyard (Lambert Vineyards Inc.) located in Niagara-on-the-Lake, Ontario, from 2005 through 2009. The two experiments that tested the combination of different water regimes and irrigation time initiation were set up in a randomized block design as follows: Baco noir - three replicates x 10 treatments [(25%, 50% and 100% of ETc) x (initiation at fruit set, lag phase and veraison) + control]; Chardonnay - three replicates x seven treatments [(25%, 50% and 100% of ETc) x (initiation at fruit set and veraison) + control]. The experiments that tested different irrigation strategies were set up on two cultivars as follows: Sauvignon blanc - four replicates x four treatments [control, fully irrigated (100% ETc), PRD (100% ETc) and RDI (25% ETc)]; Cabemet Sauvignon - four replicates x five treatments [control, fully irrigated (100% ETc), PRD (100% ETc), RDI (50% ETc) and RDI (25% ETc)]. The controls in each experiment were nonirrigated. The irrigation treatments were compared for many variables related to soil water status, vine physiology, berry composition, wine sensory profile, and hormone composition [(abscisic acid (ABA) and its catabolites]. Soil moisture profile was mostly affected by irrigation treatments between 20 and 60 em depth depending on the grapevine cultivar and the regime of water applied. Overall soil moisture was consistently higher throughout the season in 100 and 50% ETc compare to the control. Transpiration rates and leaf temperature as well as shoot growth rate were the most sensitive variables to soil water status. Drip irrigation associated with RDI treatments (50% ETc and 25% ETc) had the most beneficial effects on vine physiology, fruit composition and wine varietal typicity, mainly by maintaining a balance between vegetative and reproductive parts of the vine. Neither the control nor the 100 ETc had overall a positive effect on grape composition and wine sensory typicity. The time of irrigation initiation affected the vine physiology and grape quality, the most positive effect was found in treatments initiated at lag phase and veraison. RDI treatments were overall more consistent in their positive effect on grape composition and wine varietal typicity comparing to PRD treatment. The greatest difference between non-irrigated and irrigated vines in most of the variables studied was found in 2007, the driest and hottest season of the experimental period. Soil water status had a greater and more consistent effect on red grapevine cultivars rather than on white winegrape cultivars. To understand the relationships among soil and plant water status, plant physiology and the hormonal profiles associated with it, abscisic acid (ABA) and its catabolites [phaseic acid (PA), dihydrophaseic acid (DPA), 7-hydroxy-ABA (TOH-ABA), 8' -hydroxy-ABA, neophaseic acid and abscisic acid glucose ester (ABA-GE)] were analyzed in leaves and berries from the Baco noir and Chardonnay irrigation trials over two growing seasons. ABA and some of its catabolites accurately described the water status in the vines. Endogenous ABA and some of its catabolites were strongly affected in Baco noir and Chardonnay by both the water regime (i.e. ET level) and timing of irrigation initiation. Chardonnay grapevines produced less ABA in both leaves and berries compared to Baco noir, which indicated that ABA synthesis is also cultivar dependant. ABA-GE was the main catabolite in treatments with high water deficits, while PA and DPA were higher in treatments with high water status, suggesting that the vine produced more ABA-GE under water deficits to maintain rapid control of the stomata. These differences between irrigation treatments with respect to ABA and catabolites were particularly noticeable in the dry 2007 season. Two trials using exogenous ABA investigated the effect of different concentrations of ABA and organs targeted for spraying, on grape maturation and berry composition of Cabemet Sauvignon grapevines, in two cool and wet seasons (2008-2009). The fIrst experiment consisted of three replicates x three treatments [(150 and 300 mg/L, both applications only on clusters) + untreated control] while the second experiment consisted in three replicates x four treatments [(full canopy, only clusters, and only leaves sprayed with 300 ppm ABA) + untreated control]. Exogenous ABA was effective in hastening veraison, and improving the composition of Cabemet Sauvignon. Ability of ABA to control the timing of grape berry maturation was dependant on both solution concentration and the target organ. ABA affected not only fruit composition but also yield components. Berries treated with ABA had lower weight and higher skin dry mass, which constitutes qualitative aspects desired in the wine grapes. Temporal advancement of ripening through hormonal control can lead to earlier fruit maturation, which is a distinct advantage in cooler areas or areas with a high risk of early frost occurrence. Exogenous ABA could provide considerable benefits to wine industry in terms of grape composition, wine style and schedule activities in the winery, particularly in wet and cool years. These trials provide the ftrst comprehensive data in eastern North America on the response of important hybrid and Vitis vinifera winegrape cultivars to irrigation management. Results from this study additionally might be a forward step in understanding the ABA metabolism, and its relationship with water status. Future research should be focused on ftnding the ABA threshold required to trigger the ripening process, and how this process could be controlled in cool climates.

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Isolate microorganisms that fermenting xylose to ethanol is a challenge to expand production of biofuels from lignocellulosic materials. For this work was tested fermentation of xylose by yeast strains isolated from grape skins (Vitis spp) in order to ethanol produce. The yeasts were grown in submerged fermentation with xylose as a carbohydrate source. Aliquots were taken every 24 hours to measure cell growth, sugar consumption and ethanol production. The yeast had an production ethanol average of 2.5 g / L and yield (Ye / s) 0.12 g / g, showing that they have the ability to produce ethanol from xylose.

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El resveratrol es considerado una fitoalexina pues es sintetizado como respuesta a patógenos (factores bióticos) y en condiciones climáticas adversas (factores abióticos). Actualmente existe mucho interés en él por su potencial uso en farmacología como antioxidante. Mediante cromatografía de lquidos de alta resolución (HPLC) se determinó el contenido de resveratrol en hojas de 18 accesiones de vides nativas de Puebla, México, cuatro de ellas creciendo en cuatro condiciones ambientales diferentes. Las concentraciones fueron muy variables, estimándose 39,5 μg g−1 peso fresco como valor máximo, mientras que en algunas accesiones no fue posible detectar resveratrol. Se observaron diferencias en el contenido de resveratrol para accesiones creciendo en localidades diferentes, lo que sugiere alta influencia de los factores ambientales sobre la expresión del genotipo en la inducción o inhibición de la biosíntesis de dicho metabolito secundario.

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En nuestro país no está desarrollada una técnica sensible y precisa que permita confirmar la presencia de la bacteria Agrobacterium vitis; por lo tanto es muy importante contar con herramientas analticas que permitan identificar la bacteria en vides y/o suelos para controlar la diseminación y propagación de la misma, permitiendo así a las empresas, mejorar la competitividad de sus productos en el mercado y garantizar la seguridad y calidad de la materia prima principal de la industria vitivinícola. El objetivo de este estudio es poner a punto una metodología de detección de Agrobacterium vitis sensible y de bajo costo basada en la técnica de PCR (Reacción en cadena de la polimerasa). El desarrollo de esta metodología pretende ser una herramienta importante para la industria vitivinícola al permitir detectar la presencia o ausencia de la bacteria en programas de monitoreo, tomar decisiones a tiempo y así proteger la calidad y sanidad de las vides. En el presente trabajo se empleó la metodología propuesta por Eastwell y colaboradores en 1995. La misma consistió en el aislamiento de la bacteria en medio selectivo RS, en la extracción/purificación de ADN bacteriano, amplificación por PCR, separación del producto amplificado por electroforesis y revelado por tinción, pudiéndose observar que el 100% del material con sintomatología que se utilizó presentó desarrollo de colonias características de Agrobacterium vitis. Al hacer la amplificación de los ADN y posterior revelado se observó, en primera instancia, que la amplificación no fue óptima, pero cuando se realizaron las distintas adaptaciones de la técnica se vieron diferentes resultados encontrándose que podría tratarse de: A. vitis virulento, no virulento o A. tumefaciens. Para ello fue necesario adecuar la técnica y estudiar algunos aspectos tales como las temperaturas de incubación de los medios de cultivos, evaluación de la concentración de ADN para determinar si existía una concentración mínima del mismo para su posterior amplificación. También se trabajó con diferentes concentraciones del gel de agarosa y se modificaron los volmenes de siembra y los tiempos de corrida del gel en la cuba de electroforesis. Fue posible adaptar la metodología para la identificación de cepas de Agrobacterium vitis. Los mejores resultados se evidenciaron trabajando con una temperatura de incubación de las colonias de 28 °C, con una concentración del gel de agarosa del 2 % tal como lo indicaba la técnica original, volmenes de siembra de electroforesis de 10 μl de PCR producto y un tiempo de corrida del gel en la cuba de electroforesis de 70 min a 90 Voltios. Además observamos que concentraciones de ADN superiores a 49 ng/μl registraron bandas visibles siendo las de 116 ng/μl o superiores las concentraciones más adecuadas y optimas para la obtención de bandas bien definidas y nítidas.

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Raster graphic ampelometric software was not exclusively developed for the estimation of leaf area, but also for the characterization of grapevine (Viti vinifera L.) leaves. The software was written in C-Hprogramming language, using the C-1-1- Builder 2007 for Windows 95-XP and Linux operation systems. It handles desktop-scanned images. On the image analysed with the GRA.LE.D., the user has to determine 11 points. These points are then connected and the distances between them calculated. The GRA.LE.D. software supports standard ampelometric measurements such as leaf area, angles between the veins and lengths of the veins. These measurements are recorded by the software and exported into plain ASCII text files for single or multiple samples. Twenty-two biometric data points of each leaf are identified by the GRA.LE.D. It presents the opportunity to statistically analyse experimental data, allows comparison of cultivars and enables graphic reconstruction of leaves using the Microsoft Excel Chart Wizard. The GRA. LE.D. was thoroughly calibrated and compared to other widely used instruments and methods such as photo-gravimetry, LiCor L0100, WinDIAS2.0 and ImageTool. By comparison, the GRA.LE.D. presented the most accurate measurements of leaf area, but the LiCor L0100 and the WinDIAS2.0 were faster, while the photo-gravimetric method proved to be the most time-consuming. The WinDIAS2.0 instrument was the least reliable. The GRA.LE.D. is uncomplicated, user-friendly, accurate, consistent, reliable and has wide practical application.

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The honeydew moth Cryptoblabes gnidiella is the main problem for the wineries in the Northeast of the Brazil, because it attacks the bunch and reduces the quality of the grapes and the wines. In order to stretch out the bunch to facilitate the penetration of the insecticides, it was used gibberellic acid. Six treatments with different concentrations and different dates of application, and the control were compared. The bunches are compact, characteristic of the "Syrah" grapes in the region. The grape berries were analysed at harvest and wines were made by microvinifications. The grape berries showed different qualitative characteristics, as berry weight, number of berries. °Brix, total acidity and heterogeneity of the maturation. The microvinifications were carried out with 50 kg of grapeberries into glass bottles of 20 L at 22°C, for the alcoholic and malolactic fermentations, then stabilized and bottled. The wines were tasted by a panel of ten people and compared on smell and taste plans. The tasting results showed that the control treatment was the best graded wine. The application of gibberellic acid allowed to control the honeydew moth attack, but it caused a heterogeneity on grape maturation, with a lower quality of the grapes and wines compared to the control.

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Mature berries of Pinot Noir grapevines were sampled across a latitudinal gradient in Europe, from southern Spain to central Germany. Our aim was to study the influence of latitude-dependent environmental factors on the metabolite composition (mainly phenolic compounds) of berry skins. Solar radiation variables were positively correlated with flavonols and flavanonols and, to a lesser extent, with stilbenes and cinnamic acids. The daily means of global and erythematic UV solar radiation over long periods (bud break-veraison, bud break-harvest, and veraison-harvest), and the doses and daily means in shorter development periods (5–10 days before veraison and harvest) were the variables best correlated with the phenolic profile. The ratio between trihydroxylated and monohydroxylated flavonols, which was positively correlated with antioxidant capacity, was the berry skin variable best correlated with those radiation variables. Total flavanols and total anthocyanins did not show any correlation with radiation variables. Air temperature, degree days, rainfall, and aridity indices showed fewer correlations with metabolite contents than radiation. Moreover, the latter correlations were restricted to the period veraison-harvest, where radiation, temperature, and water availability variables were correlated, making it difficult to separate the possible individual effects of each type of variable. The data show that managing environmental factors, in particular global and UV radiation, through cultural practices during specific development periods, can be useful to promote the synthesis of valuable nutraceuticals and metabolites that influence wine quality.

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A vitivinicultura no Rio Grande do Sul tem reconhecimento no cenário enolgico nacional e a Campanha Gaúcha tem sua participação neste processo. Com vinhedos implantados na década de 70, no município de Santana do Livramento- RS, para produção de uvas finas, a região tem apresentado crescente desenvolvimento com instalação de novas vinícolas. Apesar dos benefícios climáticos, a Campanha apresenta invernos irregulares, tanto na distribuição como na qualidade do frio, provocando brotações irregulares, baixa produtividade e desuniformidade na produção dos vinhedos. Buscando novas tecnologias para melhorar a qualidade de brotação e consequente qualidade produtiva, o presente trabalho objetivou avaliar o comportamento de brotação de diferentes cultivares de Vitis vinifera em relação às diferentes épocas de poda com a interação de indutores químicos de brotação.