Canopy management effects on Syrah grapevines under tropical semi-arid conditions.

The aim of this study was to evaluate the effects of shoot topping and leaf removal practices on vegetative vigor, yield and physicochemical characteristics of the 'Syrah' grape in the semi-arid tropical climate conditions of the São Francisco River Valley in the northeast of Brazil. The experiment was conducted over five growing cycles from 2010 to 2012 in a 'Syrah' commercial vineyard in the municipality of Casa Nova, Bahia, Brazil. Treatments consisted of leaf removal once or twice during fruit set or at the beginning of bunch closure, and one or two shoot toppings of the berry when pea-sized or 10 days after berry growth had commenced. Leaf removal and shoot topping did not affect yield, plant vigor components nor the main attributes of fruit quality. In contrast, there was a seasonal effect with higher yield and better balance between production and vigor in grapes produced in the first half of 2012. The Syrah grape quality was favored in cycles in the first half of the year when its ripening phase coincided with the period of mild temperatures.

Production of Syrah wines in tropical conditions of Northeast Brazil.

Twenty years ago, in the Northeast Brazil, a tropical semi-arid area, the production of tropical wines from some Vitis vinifera L. cultivars started. In this region, it is possible to harvest two times a year, between April and December, and nowadays Syrah is the most cultivated wine grape. Research works about irrigation rnanagement in Syrah started in 2000 at Brazilian Agricultural Research Corporation (Embrapa). The aim of this paper is to introduce some characteristics about the region where Syrah grapevines is being cultivated under irrigation in Northeast Brazil, and to present some results obtained from field experiments as well as some grape and wine charcteristics already determined.

Organic and nitrogen fertilization of soil under Syrah grapevine: effects on soil chemical properties and nitrate concentration.

Viticulture is an activity of great social and economic importance in the lower-middle region of the São Francisco River valley in northeastern Brazil. In this region, the fertility of soils under vineyards is generally poor. To assess the effects of organic and nitrogen fertilization on chemical properties and nitrate concentrations in an Argissolo Vermelho-Amarelo (Typic Plinthustalf), a field experiment was carried out in Petrolina, Pernambuco, on Syrah grapevines. Treatments consisted of two rates of organic fertilizer (0 and 30 m3 ha-1) and five N rates (0, 10, 20, 40, and 80 kg ha-1), in a randomized block design arranged in split plots, with five replications. The organic fertilizer levels represented the main plots and the N levels, the subplots. The source of N was urea and the source of organic fertilizer was goat manure. Irrigation was applied through a drip system and N by fertigation. At the end of the third growing season, soil chemical properties were determined and nitrate concentration in the soil solution (extracted by porous cups) was determined. Organic fertilization increased organic matter, pH, EC, P, K, Ca, Mg, Mn, sum of bases, base saturation, and CEC, but decreased exchangeable Cu concentration in the soil by complexation of Cu in the organic matter. Organic fertilization raised the nitrate concentration in the 0.20-0.40 m soil layer, making it leachable. Nitrate concentration in the soil increased as N rates increased, up to more than 300 mg kg-1 in soil and nearly 800 mg L-1 in the soil solution, becoming prone to leaching losses.

Les macroclimats viticoles mondiaux et l'influence du mesoclimat sur la typicite de la Syrah et du Muscat de Hamboug dans le sud de la France: methodologie de caracterisation.

1999

Aromatic stability of Syrah and Petit Verdot tropical wines from Brazil.

The production of fine wines in the Sub-middle of the São Francisco River Valley, Northeast of Brazil, is relatively recent, about twenty-five years ago. This region presents different characteristics, with a tropical semiarid climate, in a flat landscape. Presenting high annual average temperature, solar radiation and water in abundance for irrigation, it?s possible the scaling the grape harvests for winemaking throughout the year, allowing to obtain until two harvests per year. Several factors may affect the aromatic compounds in wines, such as viticulture practices, climatic conditions, cultivars and winemaking process. This study aimed to evaluate the aromatic stability of Syrah and Petit Verdot tropical wines elaborated in two different periods in the year. The grapes were harvested in the first and second semesters of 2009, in June and November. The wines were elaborated and then, they were bottled and analyzed in triplicate, thirty days and one year after bottling, by gas chromatography with ionization detector flame (GC-FID), to evaluate the profile and the stability of the aroma compounds. Principal component analysis was applied to discriminate between wine samples and to find the compounds responsible by the variability. The results showed that Syrah and Petit Verdot tropical wines presented different responses, for stability of higher alcohols, esters and carboxylic acids.

Influence of the vintage, clone and rootstock on the chemical characteristics of Syrah tropical wines from Brazil.

In the Northeast of Brazil, vines can produce twice a year, because annual average temperature is 26ºC, with high solar radiation and water availability for irrigation. Many cultivars have been tested according to their adaptation to the climate and soil, and the main variety used for red wines is Syrah. This work aimed to evaluate five clones of Syrah, grafted on two rootstocks, in two harvests of the second semester of 2009 and 2010, according to the chemical analyses of the wines.The clones evaluated were 100, 174, 300, 470 and 525, the rootstocks were Paulsen 1103 and IAC 313 (Golia x Vitis caribeae). Grapes were harvested in November 2009 and 2010 and the yield was evaluated. Climate characteristics of each harvest was determined and correlated to the results. Wines were elaborated in glass tanks of 20 L, with alcoholic fermentation at 25ºC for seven days, then wines were pressed and malolactic fermentation was carried out at 18ºC for 20 days. The following parameters were analyzed: alcohol content, dry extract, total anthocyanins, total phenolic index. High performance liquid chromatography was used to determine tartaric, malic, lactic and citric organic acids. Results showed that wines presented different concentrations of classical analyses, phenolics and organic acids according to the harvest date, rootstocks and clones. Principal component analysis was applied on data and clusters with wine samples were formed, explaining the variability, and results are discussed.

Effects de l'application d'acide gibbérellique (GA3) sur la qualité de raisins et de vins produits en climat tropical au Nord-Est du Brésil.

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.

Nitrate and potassium concentration in fertigated soil cultivated with wine vines.

In the semiarid region of Brazil the use of irrigation systems for applying fertilizers in horticulture is the primary means for incorporating nutrients in the soil. However, this technique still requires its use in wine vines to be assessed. In view of this, this study aimed to assess nitrate and potassium concentrations in soil fertigated with nitrogen and potassium fertilizers in 3 wine grape growing cycles. A field experiment was conducted with ?Syrah? wine grapes, in Petrolina, Pernambuco, Brazil; it assessed five nitrogen doses (0, 15, 30, 60 and 120 kg ha-1) and five K2O doses (0, 15, 30, 60 and 120 kg ha-1) applied by drip irrigation system with two emitters per plant, with a flow rate of 4 L h-1. The experimental design used was the factorial split-plot, making up 13 combinations arranged in 4 randomized blocks. Soil solution samples were collected weekly with the aid of porous cup extractors for all treatments and at depths of 0.4 and 0.6 m by determining nitrate and potassium concentrations and electrical conductivity. Increased levels of both nutrients in the irrigation water increased the availability of nitrate and potassium in the soil solution. The highest nitrate and potassium concentrations were found in the second growing cycle at both depths studied.

Eficiência do uso da água em videira Ssyrah irrigada no Submédio do Vale São Francisco.

O estudo teve como objetivo estimar a eficiência do uso da água (EUA) na videira Syrah irrigada no Submédio do Vale São Francisco, com base no rendimento em função da evapotranspiração da cultura e da transpiração máxima. Para isso, a evapotranspiração da cultura foi determinada pelo balanço de energia com base no método da razão de Bowen (ETcBERB), enquanto a transpiração máxima (TR) foi estimada pelo modelo de Penman- Monteith modificado com base no índice de área foliar da cultura. Os dados micrometeorológicos foram monitorados durante um ciclo produtivo por meio de uma estação automática localizada no parreiral. A evapotranspiração de referência (ETo) também foi calculada ao longo do experimento, pelo método de Penman-Monteith parametrizado no boletim 56 da FAO. A ETo e a ETcBERB corresponderam ao valor total de 474,0 e 376,4 mm ciclo-1, com valor médio diário de 3,9 e 3,1 mm, respectivamente. A TR oscilou entre 3,5 e 0,9 mm d-1, com volume total durante o ciclo de 284,4 mm. A EUA, com base no total de água consumida e transpirada, foi de 1,17 kg m-3 e 1,55 kg m-3, respectivamente. O método do BERB e o modelo de Penman-Monteith modificado para plantas isoladas apresentaram resultados confiáveis para estimativa da EUA sob as condições climáticas da região do Submédio do Vale São Francisco. No entanto, torna-se necessário que novos estudos nesse sentido com a cultura da videira para produção de vinhos sejam realizados, principalmente nesta região Semiárida, onde a maioria das pesquisas voltadas para o manejo do vinhedo ainda estão em desenvolvimento.

Characteristics of the vitiviniculture area in NE Brazil.

The aim of this paper is to introduce some characteristics about the region where syrah grapevines is being cultivated under irrigation in Northeast Brazil, and to present some results obtained from field experiments as well as some grape and wine characteristics already determined.