Grape Composition Research Articles

A method to predict the time of harvesting based on water consumption and changes in berry composition of table grapes (‘Superior Seedless’®) under plastic sheet covering

A method to predict the time of harvesting based on water consumption and changes in berry composition of table grapes (‘Superior Seedless’^®) under plastic sheet covering

Comprehensive Study of Variety Oenological Potential Using Statistic Tools for the Efficient Use of Non-Renewable Resources

The evaluation of the variety suitability regarding each appellation’s specificities should be a strategy for maximizing the varieties’ oenological potential while contributing to the sustainable production of quality wines, keeping their typicity and rationalizing winemaking costs. Thus, the combination of several grape physicochemical attributes, modulated by climate and vineyard characteristics, providing knowledge for each grape variety’s oenological potential, is a relevant and reliable support for winemakers’ decisions. To prove this hypothesis, six mature grape varieties from three harvests, each one from three vineyard parcels with different topographical conditions from Bairrada Appellation (Portugal), were studied using analysis of variance–simultaneous components analysis (ASCA). The effects of harvest year and parcel on grape berry weight, pH, titratable acidity, total sugars, total phenolics, antiradical activity, and volatile composition in free and glycosidically-linked forms were analyzed. The compositional plasticity of autochthonous varieties (white Arinto and Bical and red Baga, Castelão, and Touriga Nacional) was observed. Sauvignon Blanc grape composition was significantly modulated by harvest. This study represents an important contribution for the maintenance of varieties’ biodiversity while contributing to establishing their peculiarities. Autochthonous varieties, if accurately exploited, can provide higher characteristic diversity than worldwide used varieties, an aspect to be more objectively taken into consideration by winemakers.

Exploring the regional typicality of Australian Shiraz wines using untargeted metabolomics

Background and Aims Shiraz is the most widely planted winegrape cultivar in Australia. Sensory studies have indicated that different grapegrowing regions in Australia produce distinct styles of Shiraz wines that differ in flavour characteristics. The current project aimed to characterise the underlying volatile composition associated with regional Shiraz wine styles. Methods and Results Wines were selected from six geographically distinct regions and the volatile compounds were analysed using gas chromatography time-of-flight mass spectrometry to provide a comprehensive and holistic overview of the wine volatilome. A suite of R language based software enabled feature extraction and importance ranking, following an untargeted metabolomics approach. A classification model based on the random forests algorithm using the 80 most important compounds correctly associated all samples to regions. A range of these compounds, including terpenoids, benzenoids, esters, furan derivatives and aliphatic alcohols, has been associated with grape composition, winemaking influences and the ageing process. Conclusions The results suggest that the regional compositional differences in varietal wines may be influenced by all processes in the entire wine production chain. Significance of the Study The current study highlighted the chemical basis underlying the regional typicality of Australian Shiraz wines, and identified specific volatile compounds that may be associated with a region.

Water stress assessment on grapevines by using classification and regression trees.

Multiple factors, such as the vineyard environment and winemaking practices, are known to affect the development of vines as well as the final composition of grapes. Water stress promotes the synthesis of phenols and is associated with grape quality as long as it does not inhibit production. To identify the key parameters for managing water stress and grape quality, multivariate statistical analysis is essential. Classification and regression trees are methods for constructing prediction models from data, especially when data are complex and when constructing a single global model is difficult and models are challenging to interpret. The models were obtained by recursively partitioning the data space and fitting a simple prediction model within each partition. The partitioning can be represented graphically as a decision tree. This approach permitted the most decisive variables for predicting the most vulnerable vineyards and wine quality parameters associated with water stress. In Priorat AOC, Carignan grapevines had the highest water potential and abscisic acid concentration in the early growth plant stages and permitted vineyards to be classified by mesoclimate. This information is useful for identifying which measurements could most easily differentiate between early and late‐ripening vineyards. LWP and Ts during an early physiological stage (pea size) permitted warm and cold areas to be differentiated.

Spatial and temporal variability of cv. Tempranillo response within the Toro DO (Spain) and projected changes under climate change

This work aimed to analyse the spatial and temporal variability of the response of Tempranillo variety within the Toro Designation of Origin (DO) and the potential changes under climate change scenarios. The research included the analysis of phenology (bud break, bloom, veraison and maturity) and grape composition at harvest recorded in plots located at seven locations in the DO, at elevations between 667 and 779 m above the sea level (a.s.l.). Changes in phenology and composition were projected for 2050 and 2070 under two emission scenarios (Representative Concentration Pathways RCP4.5 and RCP8.5), considering the predicted changes in climate variables using an ensemble of models. Variations in the phenological timing of up to 28 days for bud break, bloom and veraison and up to 30 days for maturity were recorded during the period analysed and titratable acidity varied between 4 and 8 gL-1. The variability in phenology and grape acidity was mainly driven by temperature and available water in different periods between phenological stages, although the effect of soil properties was also confirmed. Under warmer conditions, an advance of all phenological phases was projected (up to 6, 6, 8 and 12 days by 2050 under the RCP4.5 scenario and near double under the RCP8.5 scenario). In addition, a decrease in titratable acidity is projected (about 1.1 and 1.4 gL-1 by 2050, respectively, under the RCP4.5 and the RCP8.5 scenario and up to 2.0 gL-1 by 2070 under the warmest scenario). The results were in agreement with the variability observed in years with contrasting weather conditions.

Projected effects of climate change on Tempranillo and Chardonnay varieties in La Mancha Designation of Origin

Climate is one of the components of terroir that most influences grape growth and development. Vines might suffer significant impacts under climate change, although they can be different depending on the variety and location. The aim of this study was to analyze vine phenology and grape composition variability related to weather conditions in La Mancha Designation of Origin, in Spain, and potential changes caused by climate change. The research focuses on the Tempranillo and Chardonnay varieties. Phenological dates and grape composition at ripening were evaluated for the period 2000–2019 and related to climatic variables. This information was used to project the potential variations under different emission scenarios (Representative concentration pathways RCP4.5 and RCP8.5) for 2050 and 2070. An advance in phenology is projected under climate change, for the two varieties, in agreement with that observed in years with different weather conditions. The advance for 2050 could be of 6, 11, 9, and 8 days for Tempranillo and 4, 9, 9, and 10 days for Chardonnay, respectively, for bud break, flowering, veraison, and maturity under the RCP4.5 scenario, and up to 50% higher under the PCP8.5 scenario. This advance in the phenological timing will imply ripening under warmer conditions, which could affect grape quality. A decrease in titratable acidity in both varieties is projected due to the increasing temperatures, which would have negative implications for the two varieties, and anthocyanin concentrations in Tempranillo are projected to suffer changes due to variations in temperature and in water deficits. The research presents a novelty for La Mancha DO, where there is no previous analysis in this respect. This is the first study in this vine-growing region in which projections are made on the potential changes for aforementioned vine cultivars, whose response is analyzed for expected warmer conditions in relation to those observed in cooler areas.

Unravelling the Impact of Grape Washing, SO2, and Multi-Starter Inoculation in Lab-Scale Vinification Trials of Withered Black Grapes

Wine quality is strongly affected by chemical composition and microbial population of grape must, which, in turn, are influenced by several post-harvest treatments, including grape withering. Different strategies have been suggested to manage the fermenting must microbiota, as it plays a central role in the outcomes of both spontaneous and guided fermentations. This study aimed at evaluating the impact of grape washing, SO2 addition, and selected starter culture inoculation on population dynamics, fermentation kinetics, and main oenological parameters in lab-scale trials, focusing on withered grapes usually used for Amarone production. Although grape washing treatment was effective in removing heavy metals and undesirable microorganisms from grape berry surface, inoculation of multi-starter cultures impacted more fermentation rates. Further, both grape washing and starter inoculation procedures had a remarkable impact on wine chemical characteristics, while 30 mg/L SO2 addition did not significantly affect the fermentation process. In summary, the best strategy in terms of limiting off-flavors and potentially reducing the need for SO2 addition in wine from withered grapes was the use of yeast starters, particularly mixed cultures composed by selected strains of Metschnikowia spp. and Saccharomyces cerevisiae. Application of a washing step before winemaking showed a potential to improve organoleptic characteristics of wine.

Mechanical pruning and soil organic amendments in vineyards of Syrah: effects on grape composition

Aim: The interaction of mechanized pruning systems and soil organic amendment can increase vine productivity. However, since the increase in productivity may affect grape composition, this study aimed to understand the effects of the interaction between these two practices.Methods and materials: Two field trials were implemented in Shiraz vineyards in two different wine regions. Mechanical hedge pruning was compared with hand spur pruning and four different organic amendments were tested: biochar, municipal solid waste compost, cattle manure and sewage sludge.Results: Mechanical pruning reduced the total soluble solids (TSS) and pH of the grapes, but had no effects on the other variables. Organic amendments also reduced TSS, especially sewage sludge, and tended to reduce total anthocyanins and total phenols. The effect of the interaction between both factors on grape composition was never significant. A negative relationship between yield and TSS was observed, while titratable acidity had no relationship with yield. Total anthocyanins were also negatively related to yield. A positive relation between TSS and total anthocyanins was also observed.Conclusions: The results show that the combination of mechanical pruning and soil organic amendment is a powerful tool for increasing productivity, but it has some effects on grape composition.Significance and impact of study: The reduction in some fruit composition variables showed that, while mechanical pruning does not significantly affect grape composition, the choice of type and amount of organic amendment will depend on the destination of the grapes.

Is Precision Viticulture Beneficial for the High-Yielding Lambrusco (Vitis Vinifera L.) Grapevine District?

The best Lambrusco wines are often obtained by blending a representative of the Lambrusco family (i.e. Lambrusco Salamino) with a smaller fraction of Ancellotta, a teinturier variety possessing an extraordinary quality of accumulating color. Due to the economic importance of the Lambrusco business and the rising interest in precision viticulture, a two-year trial was carried out in seven vineyard plots growing both the named varieties. A RapidEye satellite image taken on 9 August 2018, led to vigor maps based on unfiltered normalized difference vegetation index (NDVI). In both the years, ground truthing was performed on the test vines chosen within each vigor area for soil features, vegetative growth, yield, grape, and final wine composition. For data pooled over sites and years, Ancellotta showed a very clear response to NDVA-based vigor mapping as low vigor areas always achieved improved ripening in terms of higher total soluble solids (+1.24 Brix), color and phenols (+0.36 mg/kg and + 0.44mg/kg, respectively), and lower malate (-1.79 g/L) vs high vigor. Such a behavior was shown even in those cases where NDVI of different vigor levels and pruning weight were not closely correlated and, most notably, low vigor matched with a slightly higher yield as compared to high vigor plots. Overall, the high yielding Lambrusco Salamino was less responsive in terms of vine performance and grape composition versus intra-vineyard variability. This study highlights that, in Ancellotta, adjusting the vine balance toward ostensible lower vigor (i.e pruning weight ≤ 1 kg/m) would result in a superior choice in terms of improved ripening and wine profiles would not be detrimentally impacted by the yield level which, in fact, increased in some cases.

Influence of Grapevine red blotch virus (GRBV) on Idaho ‘Syrah’ grape composition

Grapevine red blotch virus (GRBV) infection was recently identified in an Idaho commercial vineyard. Fruit quality from healthy vines (no viruses detected), and GRBV positive (infected) vines was determined for ‘Syrah’ grapes from this vineyard. GRBV infected vines produced grapes with significantly lower total sugars (2.7 g/100 g difference) and lower total anthocyanins (34 mg/100 g difference). They were also lower in a single free amino acid (tryptophan, 0.4 mg of N/kg difference), yet higher in malic acid (0.13 g/100 g difference) compared to grapes from healthy vines. No significant differences were seen in total organic acids, yeast assimilable nitrogen content, total free amino acids, total phenolics, or total tannins between the grapes of healthy vines versus those of GRBV infected vines. Overall, GRBV negatively influenced grape quality by reducing total sugars and total anthocyanins, which may indicate GRBV infection delayed grape ripening and could adversely affect wine quality.

Influence of grape composition and origin, yeast strain and spontaneous fermentation on aroma profile of Corvina and Corvinone wines

Volatile composition and sensory properties of Corvina and Corvinone red wines in relationship to grape origin, yeast strain and inoculated vs. spontaneous fermentation were investigated. Experimental wines were produced using freshly harvested grapes of the two varieties coming from two different areas. The results indicated that, by affecting grape composition, grape origin had a primary impact on wine aroma chemical and sensory properties. From a chemical point of view, this effect was associated not only with grape-derived compounds but also to some extent with fermentation-derived esters. Yeast strains influence was mostly associated with higher alcohols and certain esters, whereas the main characteristic of spontaneous fermentation was increased concentration of ethyl acetate. Sensory analysis confirmed the greater impact of grape origin compared to yeast strain, indicating clusters of odor similarities which were mostly associated with variations in the content of ethyl esters, C6 alcohols, and norisoprenoids in Corvina and of norisoprenoids, cyclic terpenes, acetate esters, and ethyl acetate in Corvinone, respectively.

Effects of the irrigation regimes on grapevine cv. Bobal in a Mediterranean climate: I. Water relations, vine performance and grape composition

Climate change scenarios are predicting an increase in temperature as well as more scarce and torrential rainfall episodes. Due to this, an imbalance between grape technological and phenolic maturity is being observed detrimentally affecting grapes composition. In semi-arid areas, irrigation management is a main field practice to influence grape ripening. The goal of the present study was to investigate in Vitis vinifera L. cv. Bobal grapevine responses to three watering regimes: (i) Rainfed, (ii) deficit irrigation (DI) replacing only 35% of the estimated crop evapotranspiration (ETc) and (iii) full irrigation (FI) replacing 100% ETc. In the mid-summer, rainfed grapevines showed different degrees of water stress determined by midday stem water potentials (Ψstem) ranging from −1.1 to −1.4 MPa depening on the season. Rainfed plants had in all seasons less vigor and production and, at harvest, higher concentrations of total soluble solids (TSS) and grape phenolics compounds, as well as lower pH, with respect to the other water regimes studied. DI grapevines, generally, had intermediate values between Rainfed and FI, which presented extreme values of the studied parameters respect to Rainfed. The effects observed on grape color parameters and phenolic compounds with the Rainfed regime were mainly due to a dehydration of the berry, which lowered the yield and the weight of the berry compared to the irrigated treatments. The lower TSS accumulation in the DI berries with respect to the Rainfed, will favor obtaining wines with lower alcohol content, currently more demanded by the consumers. Besides, despite the differences obtained between water regime treatments in the TSS accumulation, the extractability of the anthocyanins was similar, which is interesting since anthocyanin extraction from grapes is prerequisite to the formation of stable red wine pigments. Although the most convenient irrigation strategy might depend to the wine style to be obtained, DI is a strategy that can help to close the gap in the imbalance between the technological and phenolic maturity, positively affecting vine yield and performance with respect to the rainfed strategy.

Role of partial dehydration in a naturally ventilated room on the mycobiota, ochratoxins, volatile profile and phenolic composition of Merlot grapes intended for wine production

Dehydration of grapes has been used in various regions of the world to produce special wines, aiming to add value to oenological products. Post-harvest dehydration in rooms may be carried out regardless of weather conditions, without the additional cost of a specific infrastructure, in addition to the benefits of protecting the grapes from damages and environmental pollution. The objective of this study was to verify, for the first time, the impact of the dehydration in a naturally ventilated room on the quality of Merlot grapes. Physicochemical characteristics, mycobiota, occurrence of mycotoxins, volatile profile and phenolic composition of grapes were monitored on 7th, 14th and 21st days of dehydration (weight loss of 10, 20 and 27%, respectively). A decrease in aw (6%), pH (4%), and berry hardness (58%), along with an increase in total soluble solid content (15%) were observed during dehydration. The presence of Pestalotiopsis clavispora, Neopestalotiopsis clavispora, Colletotrichum siamense and Alternaria porri was favored during the dehydration process, while a decrease in the occurrence of Aspergillus niger and Phanerochaete sp. was verified. A. niger isolates showed no potential to produce forms of ochratoxins. These toxins were also not found in the grape samples. Regarding the volatile profile, 1-hexanal, 2-hexenal, and 1-octanal gave rise to the corresponding alcohols during dehydration, such as 1-hexanol, 2-hexen-1-ol, and 1-octanol. Acids (hexanoic, decanoic, and 3-hexenoic) resulted in the respective ethyl esters (hexanoate, decanoate, and ethyl 3-hexenoate) during dehydration. Terpenes as limonene, myrcene, and geraniol decreased throughout dehydration, while their biotransformation products (α-terpineol, 6-methyl-5-hepten-2-one, and linalool, respectively) had an increase in concentration. The phenolic content oscillated during dehydration, with an emphasis on increased levels of four hydroxybenzoic acids (ethyl gallate, p-hydroxybenzoic acid, gallic acid-hexose, and gallic acid), two hydroxycinnamic acids (caffeic acid and caftaric acid), two flavonols (kaempeferol galactoside and quercetin) and two anthocyanins (peonidin 3-O-hexoside and delphinidin 3-O-hexoside). Grapes of satisfactory quality were produced by dehydration in a naturally ventilated room. Even small wine producers can be encouraged to implement this procedure for the diversification of oenological products, as it has no costs related to the implementation of chambers/tunnels.

RETRACTED ARTICLE: Pilot study analysis based on various fertilizers on grape cropping cultivation using advanced temperature and time agricultural bio-ethanol harvest

Climate change affects the phenology and composition of grapes and influencing eventually on winemaking, wine microbiology, chemistry, and sensory aspects. Over the next few years, the economic value of industrial bio-fuel chains has shown improvement and will be a promising source of co-product useful to sustainable agriculture systems. In a recent review of literature, many studies have reported an increase in plant parasites under organic modifications. Suppressive composts utilization is necessary to reduce agricultural waste and exhaust biomass from different bio-fuel chains. This paper introduces the advanced temperature and time agricultural bio-ethanol harvest method to increase the concentration of grape sugar levels. Under very warm temperatures, it is already seen in some areas that the metabolism of wine can be impaired. This leads to decreased accumulations of metabolites, which may influence the scent and color of the wine. To apply this residual to agriculture, diligent monitoring is required to detect early soil quality modifications. This case study is carried out using three different fertilizers ammonium sulfate, calcium ammonium nitrate, and calcium cyanamide. With no acid addition regulation, the increased pH can lead to significant modifications of the microbial ecology of musts and wines and increase the risk of organoleptic degradation and spoilage.

Understanding and managing nitrogen nutrition in grapevine: a review

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.

A comparative study of phenolic composition and antioxidant activity in commercial and experimental seedless table grapes cultivated in a Mediterranean climate

Grapes are important sources of phenolic compounds, which have multiple beneficial effects on human health. Scientific advances in the field of genetics have allowed the production of seedless table grape varieties, which are highly demanded by consumers because of their nutritional value and their easy consumption. In this study, total phenolic content (TPC), radical scavenging activity (RSA) and total anthocyanin content (TAC), were determined in 65 seedless table grape varieties (41 experimental and 24 commercial varieties). Ultra-high performance liquid chromatography coupled to an ion-trap mass spectrometry detector (UHPLC-IT-MS/MS) was used to identify and quantify some phenolic acids, flavan-3-ols, flavonols and stilbenes in 14 experimental varieties. TPC ranged from 17 to 250 mg gallic acid equivalents/100 g fresh weight (FW), RSA ranged from 15 to 269 mg Trolox equivalents/100 g FW and TAC ranged from 0 to 168 mg cyanidin-3-glucoside/100 g FW. The RSA assay showed high correlation (R2 = 0.90) between the TPC and the antioxidant activity of the 65 seedless table grapes analyzed. In the vast majority of the new experimental varieties analyzed, the TPC and TAC were similar to those of some common table grapes with seeds, indicating promising perspectives for their commercialization as potential sources of these bioactive compounds. In 6 grape varieties, high concentrations of catechin, procyanidin B2, epicatechin, quercetin 3-β-d-glucoside, 4-hydroxybenzoic acid, vanillic acid, caftaric acid and rutin were found, which would indicate that the regular intake of these varieties would be highly recommended.

The effect of the organic plant protection system on the chemical composition and quality of grapes and red wines

The biologization of viticulture is considered as a necessary attribute of its effective functioning, aimed at reducing environmental and economic risks. Comparative studies of the effect of conservative system of agriculture, including chemical crop protection, and the organic system with using preparations Extrasol, Respecta, Chitosan, Tiovit Jet on physicochemical indicators and quality of grapes and wines were carried out. We used grape cultivar ‘Bastardo magarachskiy’ from the South Coast area of Crimea. It was found that using preparations in the organic farming system contributed to the accumulation (α<0.05) of sugars in berries on average by 15%, phenolic compounds – by 13-22%, anthocyanins – by 23%, and PPO activity of the must. Experimental schemes of treatment did not influence the accumulation of aldehydes in berries. Their effect on the content of ketoacids was determined by the crop year conditions. Experimental wines were distinguished by a higher (α<0.05) content of ethyl alcohol, phenolic compounds (on average by 46%), anthocyanins (1.6 times), pyruvic and α-ketoglutaric acids (1.6 and 1.9 times) and a lower (by 20 %) concentration of aldehydes. Experimental schemes of treatment did not influence on the organoleptic of wines. The best result was shown by the complex of Tiovit Jet and Extrasol.

Impact of trellis systems and rootstocks on global phenolic composition and antioxidant activity of ‘Isabel Precoce’ grapes produced during rainy seasons in semi-arid region of Brazil

Crop components, such as trellis systems, might affect solar radiation uptake by grapevines while others, such as rootstocks, influence the vigor of the scion. Proper management provides a suitable reproductive and vegetative balance that could influence the chemical composition of grapes. This study aimed to characterize the global phenolic composition and antioxidant activity of ‘Isabel Precoce’ grapes raised for juice, growing under different trellis systems and rootstocks, in rainy seasons, in semi-Arid conditions in Brazil. With a randomized block experimental design and split-split plots over time, the overhead trellis, lyre, and vertical shoot positioning systems and two rootstocks (‘IAC 572’ and ‘IAC 766’) in the harvest seasons of January-May, 2017 and January-May, 2018 were studied. Trellis systems, rootstocks, harvest seasons and their interactions affected the characteristics of the grapes. The treatments with equivalent responses in the seasons defined the specific characteristics of the grapes. The rootstock ‘IAC 766’ provided greater bunch weight and lower acidity to the ‘Isabel Precoce’ grapes, while ‘IAC 572’ induced higher soluble solids contents. In both seasons, there was lower variation in berry resistance to compression and polyphenol and anthocyanin contents in grapes from grapevines grown on an overhead trellis. In turn, the use of lyre provided high antioxidant activity by the ABTS●+ method in 2018. The highest antioxidant activity by the DPPH● method was due to the association of overhead trellis and ‘IAC 766’. With the use of the overhead trellis, equivalent phenolic compounds and antioxidant activity during the seasons resulted in a uniform quality.

Is aromatic terpenoid composition of grapes in Northwestern Iberian wine cultivars related to variation in VviDXS1 gene?

BACKGROUND: Monoterpenes and C13-norisoprenoids are key terpenoid compounds for wine aroma. The enzyme encoded by VviDXS1 participates in terpenoid biosynthesis in grapevine fruits and gain-of-function mutations in this gene lead to characteristic muscat aroma. OBJECTIVE: To assess for VviDXS1 contribution to aroma variation in Northwestern Iberian wine cultivars, we resequenced this gene in 111 cultivars and compared grape juice terpenic composition in 12 of them. METHODS: VviDXS1 was capture-targeted for resequencing with Illumina paired-end reads, SAMtools was used for variant calling and gene haplotypes were reconstructed with PHASE. Monoterpenes and C13-norisoprenoids were quantified in free and glycosidically-bound forms from grape juice by gas chromatography-mass spectrometry. RESULTS: Terpenic composition discriminated between muscat, terpenic and neutral profiles across cultivars. While the terpenic profile of Loureira and Albariño white cultivars was not associated with muscat-like mutations, Albariño carries a V34L substitution in VviDXS1 that is also present in other aromatic cultivars and was not reported before. Tempranillo and Cabernet Sauvignon red cultivars accumulated higher levels of C13-norisoprenoids, which was not associated with specific variation in VviDXS1. CONCLUSIONS: Apart from the uncharacterized substitution present in Albariño, findings suggest that terpenoid pathway-related genes other than VviDXS1 could contribute to the aromatic attributes of these cultivars.

Macro scale analysis of Syrah vineyards under winter growing cycles: Agronomical and ecophysiological responses

In Southeast Brazil, the change of grape harvest from wet summer to dry winter through double-pruning management has improved the quality of wines, currently denominated winter wines. In order to better understand the influences of soil, macroclimate, and vineyard management in winter wines, we investigated seven vineyards in the states of Minas Gerais (Três Corações – TC, Três Pontas – TP, Cordislândia – COR, São Sebastião do Paraíso – SSP and Andradas – AND) and São Paulo (Itobi – ITO and Espirito Santo do Pinhal – PIN) during three consecutive growing seasons. The vineyards are located in warm temperate zones and grouped in four soil types: Acrudox in TC, AND and SSP, Hapludox in TP; Hapludult in AND and PIN; Eutrudept in ITO. The high clay content (> 35 %) observed in all soil types, associated to low evapotranspiration demand, avoided the occurrence of severe water stress, as observed by the high values of leaf and stem water potential, stomatal conductance, photosynthesis, and transpiration. Differences in vigor were more related to vineyard management and did not affect grape composition. Among vineyards, parameters for berry quality from ITO, such as sugar and acidity, were more associated to high soil sand content and winter temperature. No significant differences were found in anthocyanins and total phenols of berries among vineyards, suggesting that the high thermal range and low precipitation during autumn-winter, historically observed in all municipalities, seemed to be the main factor for improvement of phenolic compounds.