GiESCO

IVES 9 Tag: GiESCO

The impacts of frozen material-other-than-grapes (MOG) on aroma compounds of red wine varieties

An undesirable note called “floral taint” has been observed in red wines by winemakers in the Niagara region caused by large volumes of frozen leaves and petioles [materials-other-than-grapes (MOG)] introduced during mechanical harvest and subsequent winemaking late in the season. The volatiles, which we hypothesized are responsible, are primarily terpenes, norisoprenoids, and specific esters in frozen leaves and petioles. The purpose of this study was to investigate the volatile compounds which may cause the floral taint problem and explore how much of them (thresholds) may lead to the problem. Also, the glycosidic precursors of some of these compounds were analyzed to see the changes happening during frost events.

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Aromatic profile of six different clones of Chardonnay grape berries in Minas Gerais (Brazil)

Aromas are one of the key points in food analysis since they are related to character, quality and consequently consumer acceptance. It is not different in the winery industry, where the aromatic profile is a combination of viticultural and oenological practices. Based on the development of more aromatic clones and on the potential to produce sparkling wines at Caldas, in the southern region of Minas Gerais (Brazil) (21°55´S and 46°23´W, altitude 1,100m), the aim of this work was the determination of volatile compounds in six different clones of Chardonnay grape berries to better understand which compounds add bouquet to the wine, and additionally comprehend the impacts of the edaphoclimatic and annual conditions on the improvement of grape-growing and winemaking practices.

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Improving stilbenes in vitis Labrusca L. Grapes through methyl jasmonate applications

Grapes (Vitis sp.) are considered a major source of phenolic compounds such as flavonols, anthocyanins and stilbenes. Studies related to the beneficial effects of these compounds on health have encouraged research aimed at increasing their concentration in fruits. On this behalf, several plant growth regulators such as jasmonic acid and its volatile ester, methyl-jasmonate (MeJa), have demonstrated promising results in many fruits. However, Brazilian subtropical climate might interfere on treatment response. The present study aims to evaluate the application of MeJa in the pre-harvest period in Concord and Isabel Precoce grapes (Vitis labrusca L.).

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Service crop effects on grapevine water and nitrogen status and yield under Mediterranean climate

Service crops in vineyard can provide multiple ecosystem services but they can also lead to competition with the grapevine for soil resources in the Mediterranean region due to potential severe droughts (Garcia et al., 2018). One of the levers of action to manage this competition is the choice of species adapted in terms of growth dynamics and water and nutrients’ needs. The objectives of this study were to determine the effect of temporary service crops on grapevine water and nitrogen status and grapevine yield and yield components in a Mediterranean vineyard.

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Impact of deficit irrigation strategies on terpene concentration in Gewürztraminer grapes

Deficit irrigation is a viticultural practice often applied to improve the phenolic composition of red grapes and wines. However, the impact of this practice on grape terpenes – key aromatics for several grapes and wines – remains largely unknown. This study investigated the impact of deficit irrigation strategies on free and glycosylated terpenes in Gewürztraminer grapes. In a field study conducted in Oliver, BC, in 2016, 2017, and 2018, deficit irrigation regimes were applied to Gewürztraminer vines at different developmental stages (pre-veraison = Early Deficit, ED; post-veraison = Late Deficit, LD; throughout the season = Prolonged Deficit, PD). A well-irrigated control (CN) treatment was also established.

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Influence of ‘pinotage’ defoliation on fruit and wine quality

Among the different management techniques in Viticulture, which have
been developed with the purpose of optimizing the interception of sunlight, the photosynthetic capacity of
the plant and the microclimate of the clusters, especially in varieties that show excess vigor, the management of defoliation presents great importance. The defoliation consists of the removal of leaves that cover or that are in direct contact with the curls, which can cause physical damages in the berries, and aims to balance the relation between part area and number of fruits, providing the aeration and insolation in the interior of the vineyard, as well as reduce the incidence of rot in order to achieve greater efficiency in phytosanitary treatments and quality musts.

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Influence of planting stock and training strategy on the development and productivity of Pinot noir grapevines

For cool windy climates and/or lower vigor site situations delays in vine development during vine establishment can result in a greater number of growing seasons to achieve full yield potential. Plant material and training strategies utilized are critical factors in promoting vine development and production that is appropriate to the site conditions. The objective of this study was to evaluate nursery planting stock and training strategies for their potential to achieved advanced vine development and yield.

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Cultivation of grapes Chardonnay in soils with management practices biodynamic and conventional

The cultivation of grapes, can be accomplished with the use of different systems and practices of agricultural management, the choice of the system to be followed in the vineyard, depends on the conditions of available resources, these being: natural, economic, social, cultural and territorial. As well, it is relevant to know the characteristics of the soil of the vineyard. In the last decade, has been recurrent use of agricultural practices which date back to milinares traditions, with the aim of promoting a recovery of soil and lead the management of cultivation with less damage to the ecosystem. The study here, aimed to quantify the environmental impacts caused in the use of nutrients in conventional tillage and of grapes in the biodynamic agricultural properties in the state of Rio Grande do Sul- Brazil.

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The effect of management practices and landscape context on vineyard biodiversity

Intensification is considered one of the major drivers of biodiversity loss in farmland. The more intensive management practices that have been adopted the last decades, contributed to species declines from all taxonomic groups. Moreover, agricultural intensification has led to an important change of land use. Complex, mixed agro-ecosystems with cultivated and non-cultivated habitats have been converted to simplified, intensive and homogeneous ones with severe effects on biodiversity.

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Physiological response of new cultivars resistant to fungi confronted to drought in a semi-arid Mediterranean area

Water is one of the most limiting factors for viticulture in Mediterranean regions. Former researches showed that water shortage hampers both vegetative and reproductive developments. INRA is running programs to breed varieties carrying QTL of tolerance to major fungi, i.e. powdery and downy mildews. Some varieties have been already certified or are close to be certified. However, little is known about the response of these varieties to water deficit, which behavior is critical for their development. This study characterized physiological responses of 4 new varieties to water deficit and described relationship between them.

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Post-plant nematicide timing for northern root-knot nematode in Washington wine grapes

Vigor declines in older vineyards and poor vine establishment in replant situations have been attributed to plant-parasitic nematodes. The northern root-knot nematode, Meloidogyne hapla, is the most prevalent plant-parasitic nematode species found in Washington wine grape vineyards. Management for nematodes in established vineyards is limited to the application of post-plant nematicides. We are evaluating new nematicides that are currently not registered in grape for their efficacy in controlling M. hapla and a part of that evaluation includes improving the alignment of nematicide application timing with the vulnerable second-stage juvenile (J2) life stage of M. hapla.

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Impact of red blotch disease on Cabernet Sauvignon and Merlot grape and wine composition and wine sensory attributes

Grapevine Red Blotch disease (RB) is a recently discovered disease that has become a major concern for the viticulture and winemaking industry in California, USA. The causal
agent, Grapevine Red Blotch Virus (GRBV) was identified in 2011 and its presence was confirmed in several states in the US, in Canada, and in Switzerland. It has been demonstrated that RB compromised the regulation of ripening by suppressing specific ripening events, altering the expression patterns of transcription factors and causing hormonal imbalances in Zinfandel.

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Assessing reserve nitrogen at dormancy for predicting spring nitrogen status in Chardonnay grapevines

Nitrogen (N) supply strongly influences vine productivity and berry composition, matching availability and uptake requirements of vines during the growing season is essential to optimize vine nutrition. The nutritional status of grapevines is commonly assessed by the determination of petiole nutrient concentrations at flowering. The reserve N could also be an earlier indicator for grapevine N status, this work aimed to assess how the petiole levels relate to these perennial N reserves.

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Do high temperature extremes impact berry tannin composition?

Flavonoids, including flavonols, anthocyanins, and tannins, are
important contributors to grape and wine quality, and their biosynthesis is strongly influenced by bunch microclimate. While the synergistic effect of light and temperature has been intensively examined on flavonoids in relation to bunch exposure, studies targeting the sole effect of high temperature have mostly
focused on anthocyanins during the ripening period. With tannin biosynthesis starting around flowering, heatwaves occurring earlier in the grape growing season could be critical. Only a few papers report the impact of temperature on tannin synthesis and accumulation; to date, none have examined the effect of high temperature extremes which, in the context of climate change, relates to increases in heatwave intensity.

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Petiole phosphorus concentration is controlled by the rootstock genetic background in grapevine: is this a key for understanding rootstock conferred vigour?

Grapevine, Vitis vinifera, requires grafting on Phylloxera tolerant rootstocks of American origin in most viticultural areas of the world. The most commonly used species in rootstock creation are V. berlandieri, V. riparia and V. rupestris. Rootstocks not only provide tolerance to Phylloxera but assure the supply of water and mineral nutrients to the scion. The objective of this work was to determine to what extent rootstocks of different parentages alter the mineral composition of petioles of grapevine.

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Fertility assessment in Vitis vinifera L., cv. Alvarinho

The Portuguese wine production is characterized by wide yield fluctuations, causing considerable implications in the economic performance of this sector. The possibility of predicting the yield in advance is crucial as it enables preliminary planning and management of the available resources. The present work aims to study and evaluate two different techniques for the assessment of vine fertility. vineyards.

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Ampelograpic and genetic characterisation of grapevine genetic resources from Ozalj-Vivodina region (Croatia)

Ozalj- vivodina region is small vine growing area (only about 100 hectares of vineyards), but with significant number of old, ancient vineyards planted between 50 and 100 years ago. Trend of abandoning or replanting ancient vineyards takes place for the last 30 years. This trend results in grapevine germplasm erosion because traditional varieties are replaced with well known international varieties.Few known traditional varieties are dominantly present in ancient vineyards together with many others of unknown identity. Historical data about prevalence and characteristic of varieties on this area are very poor.

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The role of ampelographic collection in genetic improvement of native varieties and the creation new varieties

The available plant diversity is maintained in global genetic collections and germplasm banks. One of the main objectives of the study of the genetic material of vine still conducting research to characterize the genotypes and the creation of new varieties. The main ampelographic collection of the country, the largest in the Balkans, is located at the Athens Vine Institute in Lykovrisi, Attica, in an area of 70 acres. It contains more than 800 varieties, most of which are indigenous. The Institute is conducting research on the genetic improvement of native varieties and the creation new winemaking and table grape varieties of high productivity, grape quality, resistance to fungal diseases and their adaptability to stresses using the hybridization method using European high-quality varieties.

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