Publicacións

Resumen:

Black-foot disease is one of the most important soilborne diseases affecting planting material in grapevine nurseries and young vineyards. Accurate, early, and specific detection and quantification of black-foot disease causing fungi are essential to alert growers and nurseries to the presence of the pathogens in soil, and to prevent the spread of these pathogens through grapevines using certified pathogen-free planting material and development of resistance. We comparatively assessed the accuracy, efficiency, and specificity of droplet digital PCR (ddPCR) and real-time PCR (qPCR) techniques for the detection and quantification of Ilyonectria liriodendri in bulk and rhizosphere soils, as well as grapevine endorhizosphere. Fungal abundance was not affected by soil-plant fractions. Both techniques showed a high degree of correlation across the samples assessed (R2 = 0.95) with ddPCR being more sensitive to lower target concentrations. Roots of asymptomatic vines were found to be a microbial niche that is inhabited by black-foot disease fungi.

https://doi.org/10.1094/PDIS-03-19-0529-RE

Resumen:

BACKGROUND: Black-foot and Petri diseases are the main fungal diseases associated with young grapevine decline. Two field experiments were established to evaluate the preventive effect of two potential biocontrol agents (BCAs), that is Streptomyces sp. E1 + R4 and Pythium oligandrum Po37, and three BCA-commercial products containing Trichoderma atroviride SC1, Trichoderma koningii TK7 and Pseudomonas fluorescens + Bacillus atrophaeus on fungal infection in grafted plants and plant growth parameters. RESULTS: The effectiveness of some BCA in reducing the incidence and severity of both diseases was dependent on the plant part analyzed and the plant age. No single BCA application was able to control both diseases. Streptomyces sp. E1 + R4 were able to reduce significantly the infection of the most prevalent black-foot disease fungi while P. oligandrum Po37 and Trichoderma spp. were able to reduce significantly Phaeomoniella chlamydospora and Phaeoacremonium minimum (Petri disease) infection. BCA treatments had no effect on the shoot weight, and root weight was significantly lower in all BCA treatments with respect to the control. CONCLUSIONS: The combination of the disease-suppressive activity of two or more beneficial microbes in a biocontrol preparation is required to prevent infection by black-foot and Petri disease fungi in vineyards.

DOI 10.1002/ps.6064

Resumen:

The grapevine trunk diseases (GTD) Botryosphaeria dieback and esca threaten the sustainability of the grapevine industry worldwide. This study aimed to evaluate and compare the efficacy of various liquid (pyraclostrobin + boscalid and thiophanate methyl) and paste (paste + tebuconazole) formulation fungicide treatments as well as biological control agents (Trichoderma atroviride SC1 and T. atroviride I-1237), for their potential to prevent infection of grapevine pruning wounds by Diplodia seriata and Phaeomoniella chlamydospora in two field trials over two growing seasons. Treatments were applied to freshly pruned wounds following label dosages’ recommendations. After 24 h, wounds were artificially inoculated with 400 spores of D. seriata or 800 spores of P. chlamydospora. Isolations were made from the treated pruning wounds after 12 months to evaluate the efficacy of the treatments. Fungicide formulations were superior to Trichoderma-based treatments for the control of both pathogens during both growing seasons, with mean percent disease control of 44–95% for D. seriata and 46–67% for P. chlamydospora. Pyraclostrobin + boscalid was the most effective treatment. Trichoderma atroviride-based treatments did not reduce infection by D. seriata or P. chlamydospora compared to the untreated inoculated control in both vineyards and seasons. This study represents the first scientific comparative vineyard assessment of both commercial and biological treatments to protect pruning wounds against GTD fungi in Europe and provides growers with tangible preventative control practices to minimize yield losses due to GTD.

https://doi.org/10.1016/j.cropro.2020.105465

Resumen:

Las enfermedades de la madera de la vid son una de las principales causas de su muerte temprana. La falta de medidas curativas hace que su manejo sea muy difícil y requiera de una estrategia de manejo integrado combinando tratamientos físicos, químicos, biológicos y prácticas culturales tanto en plantas de vivero como en viñedos recién establecidos.

http://www.revistaagricultura.com/vid/vinedo/manejo-integrado-de-las-enfermedades-de-la-madera-en-viveros-de-vid_11640_166_14567_0_1_in.html

Resumen:

En el presente trabajo se evaluó, en dos campañas vitícolas, la eficacia de varios productos biológicos, químicos o combinación de materias activas fungicidas con una barrera física para la protección de heridas de poda contra infecciones artificiales por hongos de la madera en dos viñedos de la DO Valdeorras (Galicia).

Revista VIDA RURAL, Agricultura 2020; 22-26.

Resumen:

Timing of pruning may affect wound susceptibility to wood-invading fungi, such as those associated with grapevine trunk diseases (GTDs). This study aimed to determine the effect of pruning time on natural fungal infection in six vineyards in Galicia, Spain, during two periods of three months each, from November to February and from February to May by ITS2 high-throughput amplicon sequencing. Fungal microbiome composition did not differ significantly with year of sampling. Pruned canes harboured a core community of fungal species, which appeared to be independent of the infection period. Accumulated rainfall over 8 and 11 weeks after pruning positively correlated with the total fungal microbiome. A seasonal effect on GTD fungal infection was detected for most genera, with a higher percent detected after pruning in February (winter) as compared with that of pruning in November (midautumn). Early pruning is recommended to reduce the infections caused by GTD fungi in Galicia.

https://doi.org/10.1016/j.funeco.2020.100994

Resumen:

El conocimiento de las interacciones que se producen entre el microbioma presente en el suelo, en la rizosfera y la colonización de las raíces de las vides puede resultar clave para determinar los procesos de infección por hongos asociados a las enfermedades de la madera de la vid (EMV), principalmente la enfermedad del pie negro. Por ello, en este estudio se evaluó, en primer lugar, los cambios en la dinámica de las comunidades fúngicas del suelo, la rizosfera y la endorizosfera en cinco viñedos jóvenes de La Rioja mediante secuenciación masiva de amplicones de la región ITS2 con el sistema MiSeq de Illumina. Además, se cuantificaron los hongos asociados al pie negro mediante la puesta a punto de un protocolo innovador de cuantificación absoluta basado en la tec­nología de la droplet digital PCR (ddPCR), comparando su eficiencia y sensibilidad con el sistema de cuantifi­cación relativa de PCR a tiempo real (qPCR). Las comunidades fúngicas del suelo, su diversidad y composición se vieron afectadas en gran medida por la fracción suelo-planta, mientras que la variación de las mismas entre viñedos fue baja. Las raíces de vides asintomáticas mostraron ser un nicho microbiano habitado por hongos asociados a las EMV, lo que abre nuevas perspectivas en el estudio del papel endofítico de estos patógenos en la vid. Los resultados de la cuantificación de hongos asociados al pie negro mediante ambas técnicas mostraron una correlación significativa, si bien la ddPCR fue la técnica más sensible y precisa en la detección de bajas con­centraciones. Ambas técnicas mostraron que la abundancia de hongos asociados al pie negro no se vio afectada por los distintos compartimentos suelo-planta.

https://www.phytoma.com/la-revista/phytohemeroteca/311-agosto-septiembre-2019/variaciones-espaciales-en-las-comunidades-fungicas-en-suelos-de-vinedos-y-su-interaccion-con-la-enfermedad-del-pie-negro

Resumen:

Plant compartments provide unique niches that lead to specific microbial associations. The microbiota colonizing the endophytic compartment (endorhizosphere) and the rhizosphere contribute to productivity, plant growth, phytoremediation and carbon sequestration. The main objective of this study was to investigate how fungal communities are enriched in different habitats outside and inside of grapevine roots. For this purpose, the spatial dynamics of the fungal communities associated with three soil-plant compartments (bulk soil, rhizosphere and endorhizosphere) were characterized by ITS high-throughput amplicon sequencing (HTAS). Fungal communities were largely affected in their diversity and composition by soil-plant compartments, whereas the spatial variation (i.e. across five vineyards) was low. The endorhizosphere compartment differed most from the other two, suggesting that the root tissues entail a barrier for fungal colonization. The results of functional prediction via FUNGuild suggested an increase in the relative abundances of potential plant pathogens, endophytes and arbuscular mycorrhiza, and a decrease in wood, dung and undefined saprotrophs from bulk soil towards the endorhizosphere. Roots of asymptomatic vines were a microbial niche that is inhabited by soilborne fungi associated with grapevine trunk diseases, which opens up new perspectives in the study of the endophytic role of these pathogens on grapevines. Results obtained in this study provide helpful information to better know how the host shapes its microbiome and the implications for vineyard productivity and management.

https://doi.org/10.1016/j.funeco.2019.07.003

Resumen:

BACKGROUND: Control of Botrytis bunch rot (BBR) is currently based on the application of fungicides at four timings corresponding to specific growth stages of vines: end of flowering (A), pre-bunch closure (B), veraison (C) and before harvest (D). The current research provides a network meta-analysis of 116 studies conducted between 1963 and 2016 in nine countries, in which 14 strategies (based on combinations of 1, 2, 3, or 4 sprays applied in A, B, C, and/or D) were compared. RESULTS: When a one-spray strategy was applied, BBR control was more effective with sprays applied in A, C, or D than B.With a two-spray strategy, strategy AC provided similar control as strategy BC; strategy CD also provided good control. For a 3-spray strategy, the best disease control was consistently obtained with strategy ACD. Four-spray strategy ABCD provided the best control but often involved needless sprays so that the routine application of four sprays is not justified. CONCLUSIONS: Spraying at timing A seems to be very important for achieving efficient and flexible disease control. Flexibilityis reduced by spraying at timing B rather than A.

DOI 10.1002/ps.5116

Resumen:

Esca and leaf stripe diseases are two of the most destructive grapevine trunk diseases which are caused by a complex of fungal species, being the Ascomycete Phaeomoniella chlamydospora the most frequently isolated species from affected vines. To date, no curative measures are known for control these diseases; therefore, planting disease-resistant cultivars is a time-tested and sustainable approach for disease management. The aim of this study was to identify sources of resistance to P. chlamydospora among minority and commercial grapevine germplasm collections in Spain. For this purpose, 15 and 38 cultivars from the ITACyL and the EVEGA collections, respectively, were selected based on the visual assessment of symptom expression in standing vines over the last 3 years, and inoculated with P. chlamydospora in a detached cutting assay under greenhouse conditions over two consecutive years. Seven months after inoculation, cuttings were collected and inspected for lesion length. The severity of internal wood symptoms caused by P. chlamydospora varied considerably amongst the cultivars. No foliar symptoms were observed during the experiment. All cultivars were susceptible to fungal necrotic infection, indicating that there is no evidence of qualitative resistance to this Ascomycete fungus.

https://doi.org/10.1016/j.scienta.2018.10.049

Resumen:

Las enfermedades fúngicas de la madera de la vid (EMV) son actualmente una de las patologías más dañinas que afectan a este cultivo a nivel mundial. El objetivo de este estudio fue evaluar la susceptibilidad de 44 cultivares de la colección de germoplasma de la “Estación de Viticultura e Enoloxía de Galicia” (EVEGA-INGACAL) frente a los hongos: Eutypa lata, Neofusicoccum parvum, Phaeoacremonium minimum y Phaeomoniella chlamydospora. Para la inoculación, se utilizaron estaquillas de un año plantadas en maceta, realizándoles una herida entre los dos nudos superiores con un sacabocados de 6 mm. A continuación, se colocaron discos de agar y micelio del mismo diámetro, utilizando como controles discos de agar estéril. Se utilizaron 12 estaquillas por cultivar y tratamiento. Las estaquillas inoculadas se colocaron en un invernadero a 25°C en una distribución totalmente al azar. A los 5, 6 y 7 meses tras la inoculación (dependiendo del hongo), las estaquillas se evaluaron midiendo el desarrollo de las lesiones internas producidas por el hongo. Todos los cultivares fueron susceptibles a la infección, pero la severidad de las necrosis en la madera varió significativamente, lo cual indica que existen genotipos más tolerantes a las infecciones causadas por hongos asociados a las EMV.

Resumen:

In June 2017, symptoms of black foot disease were observed on 2-year-old grapevines (Vitis vinifera L.) cv. Malvasía grafted on 110 Richter rootstock and on 2-year-old grapevines cv. Garnacha Tintorera grafted on 110 Richter rootstock in Mendavia (Navarra Province, northern Spain) and Requena (Valencia Province, eastern Spain), respectively. Affected plants showed delayed budding with low vigor and leaf chlorosis. Roots showed black discoloration and necrosis of wood tissues. Root fragments were cut, washed under running tap water, surface sterilized for 1 min in a 1.5% sodium hypochlorite solution, and washed twice with sterile distilled water. Small pieces of discolored or necrotic tissues were planted onto malt extract agar (MEA) supplemented with 0.4 g l-1 of streptomycin sulfate. Plates were incubated at 25oC in the dark for 10 days and all colonies were transferred to PDA. A Cylindrocarpon-like asexual morph fungus was consistently isolated from necrotic root tissues. Single conidial isolates were obtained and grown on PDA and incubated at 25oC for 10 days in darkness. The isolates developed buff to cinnamon and felty abundant mycelium. All isolates produced slightly curved one-septate (16.0-) 21.6 (-26.5) x (4.5-) 6.1 (-7.8) μm, two septate (19.5- ) 25.9 (-35.0) x (5.0-) 6.6 (-7.9) μm, and three septate (22.5-) 31.3 (-47.5) x (5.5-) 7.1 (- 8.9) μm macroconidia, and aseptate (4.0-) 7.7 (-12.5) x (2.5-) 3.3 (-5.4) μm and one septate (8.5-) 12.5 (-17.5) x (3.5-) 5.1 (-6.2) μm microconidia. DNA sequence analysis of the partial histone H3 gene was obtained for isolates BV-816 and GIHF-156 and deposited in GenBank (Accession Nos. MH229866 and MH229867). These sequences showed high similarity (99%) to the sequence of Ilyonectria robusta (A.A. Hildebr.) A. Cabral & Crous (GenBank Accession No. JF735517), in agreement with morphological features (Cabral et al. 2012). Pathogenicity tests were conduced on 2-month-old grapevine seedlings (cv. Tempranillo) using both isolates. Fifteen seedlings per isolate were inoculated when two to three leaves had emerged by immersing the roots in a 106 mL-1 conidial suspension for 30 s. Fifteen control plants were inoculated with sterile distilled water. Seedlings were maintained in a growth chamber at 25oC. Symptoms developed on all plants 15 days after inoculation and consisted in reduced vigor, interveinal chlorosis and necrosis of the leaves, necrotic root lesions with a reduction in root biomass, and plant death. The fungus was reisolated from the roots of affected seedlings and identified as I. robusta, completing Koch’s postulates. No symptoms were observed on the control plants. To our knowledge, this is the first report of I. robusta causing black foot disease of grapevine in Spain.

Resumen:

Adopting cover crops for vineyard soil management can provide several benefits, includingsoilprotection,reductionsinvinevigor,andenhancementsinberrycomposition. However, the effects of this practice on wine aroma have seldom been addressed. This study aimed to determine the influence of different cover crops and soil tillage on the must and wine amino acid composition and wine volatile compounds of the red cultivar, ‘Mencía’ (Vitis vinifera L.), grown in Northwest Spain. Treatments consisted of soil tillage (ST), native vegetation (NV), English ryegrass (ER), and subterranean clover (SC). Cover crops did not alter the macro-constituents of musts; however, musts from NV and SC tended to lower concentrations of amino acids. Some color attributes of wines were influenced by cover crops in the vineyard. Methanol andtrans-linalool oxide (pyran) concentrations in wines were significantly affected by soil management. Professional tasters encountered differences in visual, aroma, and palate descriptors of wines depending on the treatment imposed in the vineyard. These alterations in sensory properties seemed to obey to slight modifications of wine chemical characteristics due to vineyard soil management. According to these results, cover crops might be useful for modulating wine aroma in humid climates.

DOI: 10.3390/beverages4040076

Resumen:

Concentrations of amino acids and volatile compounds of a given grapevine cultivar might be altered by interannual climate variability and management practices such as irrigation. These compounds determine, in part, aroma and sensory characteristics of wines. The current study aimed at assessing the amino acid profile of musts and wines and the volatile composition of wines from Vitis vinifera (L.) cultivar ‘Godello’ grown in the Ribeiro Designation of Origin (NW Spain) under rain-fed and supplementary irrigation (SI) conditions over three years (2012-2014). Supplementary irrigation increased must titratable acidity. However, must amino acid concentrations were not significantly altered by SI. In contrast, the concentrations of ethyl lactate and geraniol were greater in wines from the SI treatment. Significant correlations between amino acids in musts and volatiles in wines were observed. Our results highlight the low impact of SI on must and wine composition, likely due to the low level of water stress experienced by Godello vines. Understanding the effects of SI on wine properties could aid to adapt management practices in the future.

DOI: 10.1016/j.foodres.2018.05.074

Resumen:
Soil processes are characterized by a great degree of heterogeneity, which may be assessed by scaling properties. The aims of the current study were to describe the dynamics of soil water content at three depths in a vineyard under rain-fed and irrigation conditions and to assess the multifractality of these time data series. Frequency domain reflectometry (FDR) sensors were used for automatically monitoring soil water content in a vineyard located in Leiro (Ourense, northwest Spain). Data were registered at 30 min intervals at three depths (20, 40, and 60 cm) between 14 June and 26 August 2011 and 2012. Two treatments were considered: rain-fed and irrigation to 50% crop evapotranspiration.
Soil water content data series obeyed power laws and tended to behave as multifractals. Values for entropy (D1) and correlation (D2) dimensions were lower in the series from the irrigation treatment. The Hölder exponent of order zero (0) was similar between treatments; however, the widths of the singularity spectra, f .
/, were greater under irrigation conditions. Multifractality indices slightly decreased with depth. These results suggest that singularity and Rényi spectra were useful for characterizing the time variability of soil water content, distinguishing patterns among series registered under rain-fed and irrigation treatments.

Acceso a la publicación: http://www.sech.info/ACTAS/Acta%20n%C2%BA%2076.%20II%20Jornadas%20del%20Grupo%20de%20Viticultura/Acta%20n%C2%BA%2076.%20II%20Jornadas%20del%20Grupo%20de%20Viticultura.pdf

Resumen:
Inter-annual climate variability, mainly rainfall temporal distribution, is a critical factor for scheduling irrigation. In order to efficiently manage precision irrigation systems for Vitis vinifera (L.), their effects on plant physiology, and vineyard soils, together with yield and quality parameters, need to be understood. The current study was conducted on two grapevine cultivars from Galicia (NW-Spain), cv. ‘Albariño’ and ‘Godello’, during 2012–2014, in two different Designations of Origin (DO): Rías Baixas and Valdeorras. The treatments were rainfed (R) and surface drip irrigation (DI) in DO Rías Baixas, adding subsurface drip irrigation (SDI) in DO Valdeorras, with four replicates (7 plants each). Irrigation was triggered at fruit set, when midday stem water potential (Ψstem) dropped to −0.5 MPa, and stopped 15 days before harvest in DO Valdeorras; but it was managed by the vinegrower in DO Rías Baixas. Different bioclimatic indices were calculated to characterize each season and location. Soil water content and Ψstem were periodically measured to assess vineyard water status. Yield and juice quality attributes were determined. Water productivity indices were calculated to compare locations and cultivars. Differences between DOs were observed regarding bioclimatic indices, which indicated temperate and very cool nights for cv. ‘Godello’. In the case of ‘Albariño’, warmer nights were observed. In DO Valdeorras, the differences between treatments in Ψstem were never higher than −0.19 MPa; whereas they were almost null in DO Rías Baixas. Yield parameters showed a worse overall productive performance for the R treatment, with lower yields in 2012 and 2013. Qualitative parameters were stable over the three growing seasons studied. Adjusting irrigation schedules for a given season using Ψstem measurements and considering the phenological stage of the vine might help to obtain homogeneous harvests, both in yield and quality. Water productivity indices related with grape yield and pruning weight showed that, in a temperate climate, vegetative growth has an important weight in vineyard water use.

Acceso a la publicación: http://www.sciencedirect.com/science/article/pii/S0378377415300573

Resumen:
Vineyards are usually managed by tilling the inter-rows to avoid competition from other plants for soil water and nutrients. However, in humid and sub-humid climates, such as that of NW Spain, cover crops may be an advantage for controlling vine vegetative growth and improving berry composition, while reducing management costs. The current study was conducted over three consecutive growing seasons (2012-2014) to assess the effects of establishing three permanent cover crop treatments on water relations, vine physiology, yield and berry composition of a vineyard of the red cultivar ‘Mencía’ (Vitis vinifera L.) located in Leiro, Ourense. Treatments consisted of four different soil management systems: ST, soil tillage; NV, native vegetation; ER, English ryegrass (Lolium perenne L.); and SC, subterranean clover (Trifolium subterraneum L.). Midday stem water potential was more negative in the native vegetation treatment, causing significant reductions in leaf stomatal conductance on certain dates. Total vine leaf area and pruning weight was reduced in the cover crop treatments in the last year of the experiment. Yield was unaffected by the presence of a cover crop. No significant differences among treatments were observed for berry composition; however, wines were positively affected by the SC treatment (higher tannin content and colour intensity and lower malic acid concentration when compared with ST). Wines from the cover crop treatments were preferred by taste panelists. These results indicate that in humid climates cover crop treatments can be useful for reducing vine vegetative growth without compromising yield and berry quality.

Acceso a la publicación: http://www.ajevonline.org

Resumen:
Amino acids constitute a source for yeast metabolism and, thus are of paramount importance to wine flavour and aroma. Their concentrations in must depend greatly on grape variety. The aim of this work was to describe the amino acids profile of two white grapevine varieties: ‘Godello’ and ‘Treixadura’, produced in Galicia (NW Spain). The study was carried out over two consecutive vintages (2012 and 2013). Amino acids profiles of the musts were determined using HPLC. Although the musts from the two varieties presented common major and minor amino acids, the greatest contents were observed for ‘Treixadura’. ‘Godello’ and ‘Treixadura’ varieties were arginine-accumulators, since this was the amino acid found at the highest level in the musts from the two cultivars. Amino acids contents were higher in 2012 than in 2013, likely due to climate differences between years.

Acceso a la publicación: http://www.ctv-jve-journal.org/

Resumen:
Galicia is a region located in NW Spain characterized by high rainfall amounts; however, climate change is altering the temporal and spatial distribution of rainfall. Thus, vinegrowers are concerned about this climate variability that may affect grape production and quality and, therefore, drip irrigation systems are increasingly being installed in Galician vineyards. Hence, the development of efficient irrigation management practices is required. In this regard, a field experiment was carried out over three seasons (2012–2014) on white Vitis vinifera L. cv. ‘Godello’ and ‘Treixadura’ in order to assess the effects of deficit irrigation on vine performance and must and wine composition. Rain-fed vines were compared with a treatment irrigated to 50% of the estimated crop evapotranspiration (ETc) from bloom to two weeks before harvest. Both cultivars showed more positive plant water status under irrigation than under rain-fed conditions; however, stomatal conductance and chlorophyll fluorescence attributes were similar between treatments. Yield was unaffected by irrigation except for Treixadura cultivar in 2014 (25% increase). On the contrary, irrigation increased pruning weight, around 15%, for both cultivars. Total soluble solids of the must decreased and total acidity increased with irrigation; however, the wines were very similar between treatments. Water productivity was higher under rain-fed conditions for Godello, which led to similar gross incomes between treatments but with a lower production cost for rain-fed. In the case of Treixadura, significantly higher gross incomes were estimated for irrigation only in the last year of studies, which may not justify the use of irrigation. Therefore, irrigation does not seem an economically viable agricultural practice under the conditions of this trial.

Acceso a la publicación: http://www.sciencedirect.com/science/article/pii/S0378377415300573

Resumen:
Today, bentonite continues to be one of the most used products to remove proteins in white wines in order to avoid their precipitation in bottles. However, excessive use of bentonite has negative effects on the aroma of final wine, so the optimization of the dose and the time of its application are important for winemakers. This paper analyzes how applying an equal dose of bentonite at different stages (must clarification; beginning, middle, and end of fermentation) affects the macromolecular profile, protein stability, physical-chemical characteristics and aromatic profile of the wine obtained. The results showed the addition during fermentation (especially in the middle and at the end) reduced the total dose required for protein stabilization of Albariño wines and maintained the sensory characteristics of this variety.

Acceso a la publicación: http://www.journals.elsevier.com/food-chemistry/

Resumen:
Monovarietal red wines from Caíño da Terra, Caíño Longo, Caíño Bravo and Caíño Redondo grape varieties were analysed in order to determine the volatile composition in terms of fermentative compounds. The wines were also sensorially evaluated with
the aim of defining their sensory profile based on the descriptive attributes provided by a panel. Significant analytical and sensorial differences were found among the four wine cultivars. The wine from the Caíño Redondo cultivar showed a lower content for the majority of the aromatic compounds, whereas wines from Caíño Longo and Caíño da Terra cultivars were the most aromatic ones with higher contents in ethyl esters and acetates. Odour activity values (OAV) for all volatile compounds identified were calculated and classified into seven odorant series, fruity, floral, sweet and fatty being the series with higher contribution to the aroma profile of the evaluated wines. Based on the individual odour thresholds, wines from Caíño Longo were the most aromatic, owing to the higher OAV values found for the majority of the volatiles analysed, mainly ethyl esters. Principal component analysis accounted for 81.19% of the variance, thus showing a good separation of the wine cultivars according to the volatile compounds.

Acceso a la publicación: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292050-0416

Resumen:
Aims: To evaluate the usefulness of predawn water potential (Y_pd) to assess the water status of Galician grapevine cultivars for irrigation purposes.

Methods and results: Three Galician white grapevine cultivars (Albariño, Godello and Treixadura) were subjected to rain-fed and irrigation conditions during the 2013 growing season. Diurnal changes in leaf water potential (Y_l) were measured using a pressure chamber on days with high evapotranspiration demand. Stem water potential (Y_s) was measured at midday. Ypd was not able to discriminate between treatments, whereas Y_l and Y_s at midday were able to detect significant differences in water status among plants.

Conclusion: Y_pd was not useful to evaluate vine water status under the Galician climatic conditions. In contrast, both Y_l and Y_s were effective for detecting differences between treatments and can thus be used for irrigation management purposes.

Significance and impact of the study: This is the first study evaluating water status of Galician grapevine cultivars. It also provides useful information about the strategy for its control through measurements of midday Y_l or Y_s.

Acceso a la publicación: http://www.jisvv.com/

Resumen:
Apenas se conoce la respuesta enológica de las variedades tradicionales gallegas a un aporte suplementario de agua por medio del riego. En el contexto de cambio climático en el que nos encontramos, aumenta el interés por conocer si el riego puede afectar a la calidad de los vinos blancos gallegos. Es por ello que el equipo investigador de la Estación de Viticultura y Enología de Galicia (EVEGA) ha puesto en marcha una investigación para conocer la influencia de la irrigación sobre la calidad de los vinos gallegos. Este trabajo se engloba dentro de un proyecto más amplio, en coordinación con el equipo “Fertirriego y necesidades hídricas” de la Universidad de Santiago de Compostela, financiado por el INIA, con un 70% de fondos FEDER, que lleva por título “Influencia de diferentes prácticas culturales en el estado hídrico de viñedos del Noroeste de España: valoración agronómica y económica”. En este artículo, se presentan los resultados correspondientes a una experiencia en la Denominación de Origen Ribeiro, sobre tres variedades blancas de cultivo tradicional: Treixadura, Godello y Albariño. El ensayo consistió en dos tratamientos de manejo del viñedo: un testigo de secano y un riego al 70% de la evapotranspiración potencial. Los vinos procedentes de cada tratamiento fueron catados por un panel de 8 catadores. Se observaron diferencias, para las tres variedades consideradas, en el índice hedónico y en varios descriptores dependiendo del tratamiento de riego. En general, los vinos procedentes de secano fueron mejor valorados.

Web de la revista: http://www.revistaenologos.es/influencia-del-riego-en-el-perfil-sensorial-de-vinos-de-tres-variedades-blancas-aut%C3%B3_investigacion-ciencia_43.html

Resumen:
El potencial hídrico de tallo a mediodía en DO Valdeorras, descendió desde -0,4 MPa (30/05) hasta -1,1 MPa en vendimia (07/09). En la DO Monterrei, el potencial hídrico de tallo se situó en torno a -1,4 MPa desde finales de agosto a vendimia (04/10). El menor nivel de estrés hídrico en A Rúa, provoca rendimientos agronómicos mayores en regadío. Los parámetros químicos de los mostos de secano se mantienen homogéneos entre ambas regiones, en torno a 13,5 (GAP) y 6,5 g l^-1 de acidez total.

Web de la revista: http://www.sevi.net/

Resumen:
El cultivo de la vid en Galicia ha estado y está siendo sometido a una fuerte erosión genética, consecuencia inicialmente de la acción devastadora de la filoxera sobre los viñedos europeos, y de hongos fitopatógenos como mildiu y oídio. Hoy las causas de esta erosión se deben más a un mercado centrado en la producción de vino a partir de un escaso número de cultivares, avalado por los Reglamentos de las Denominaciones de Origen que contemplan un reducido número de variedades para el cultivo de la vid. Para evitar esta pérdida de recursos genéticos se han creado colecciones de vides, en las que se conservan ejemplares que en algún momento formaron parte de nuestros viñedos. Estas colecciones constituyen un importante punto de partida para conocer el origen y la diversidad varietal existente (De Andres et al. 2012, Ibañez et al. 2003). El objetivo de este trabajo es mostrar la variabilidad de los recursos genéticos de vid existentes en la comunidad autónoma gallega y las relaciones genéticas y geográficas existentes entre ellos lo que nos permitirá inferir el origen de esta variabilidad.

Resumen:

Aims: To evaluate the influence of native Saccharomyces cerevisiae strains for making red wine from Mencía: fermentative ability, inoculation success, and sensory and chemical characteristics of wines.

Methods and Results: Indigenous yeast strains were inoculated and their inoculation success was followed by mt-DNA-RFLP of yeast randomly isolated at different stages of fermentation. The results showed that the added yeast strains fermented in co-dominance with a strain resident in the winery, which also controlled the spontaneous processes. Chemical analysis of basic wine parameters using official methodology showed significant differences among wines for alcohol degree and volatile acidity. Fermentative aroma compounds were determined by gas chromatography. Wines made with different yeast strains varied in higher alcohol content, esters, 2-phenylethanol, ethyl lactate and acetoin. Sensory analysis indicated that wine from strain Sc24 reached the greatest punctuation at a global level whereas that from Sc11 wine achieved the highest scores for colour intensity, structure and fruity character.

Conclusions: The application of selected S. cerevisiae strains allowed us to obtain differentiated wines from the chemical and sensory points of view.

Significance and impact of the study: The results confirmed that indigenous yeasts can be used to elaborate singular wines, and they may constitute a useful tool to diversify Mencía wines.

Resumen:
The impact of the distillation system and yeast strain on the chemical and aromatic profile of kiwi spirits was investigated.Three fermentations of kiwi fruits were carried out, two with selected yeasts (KL1 and KL2) and one spontaneous (KL3). The obtained kiwi wines were distilled using two distillation systems (Charentais alembic and packed column), and the resulting spirits were analysed by direct injection gas chromatography. Kiwi spirits obtained with the packed column had the highest concentrations of esters C6–C10 and monoterpenols, while the alembic spirits had the highest concentrations of ethyl acetate, methyl acetate and higher alcohols. Three principal components derived from the chemical composition data explained 96.6% of the variance. Principal component 1 differentiated alembic from packed column distillates, principal component 2 distinguished KL3 spirits and principal component 3 distinguished KL1 spirits. Kiwi spirits distilled with the packed column were preferred by consumers. The predominant sensory descriptors in the packed column kiwi spirits were floral, fruity and spicy, while burnt/smoky and pungent were the principal aroma descriptors in alembic spirits. Moreover, significantly higher ethanol yields and ethanol strengths were obtained with the packed column distillation system. The observed influence of the yeast strains on preference and ethanol yields was minor.

Resumen:
Orujo is a traditional alcoholic beverage produced in Galicia (northwest Spain) from distillation of grape pomace, a byproduct of the winemaking industry. In this study, the effect of the distillation system (copper charentais alembic versus packed column) and the yeast strain (native yeast L1 versus commercial yeast L2) on the chemical and sensory characteristics of orujo obtained from Albariño (Vitis vinifera L.) grape pomace has been analyzed. Principal component analysis, with two components explaining 74% of the variance, is able to clearly differentiate the distillates according to distillation system and yeast strain. Principal component 1, mainly defined by C6−C12 esters, isoamyl octanoate, and methanol, differentiates L1 from L2 distillates. In turn, principal component 2, mainly defined by linear alcohols, linalool, and 1-hexenol, differentiates alembic from packed column distillates. In addition, an aroma descriptive test reveals that the distillate obtained with a packed column from a pomace fermented with L1 presented the highest positive general impression, which is associated with the highest fruity and smallest solvent aroma scores. Moreover, chemical analysis shows that use of a packed column increases average ethanol recovery by 12%, increases the concentration of C6−C12 esters by 25%, and reduces the concentration of higher alcohols by 21%. In turn, L2 yeast obtained lower scores in the alembic distillates aroma profile. In addition, with L1, 9% higher ethanol yields were achieved, and L2 distillates contained 34%−40% more methanol than L1 distillates.

Resumen:
The fermentative ability of five autochthonous Saccharomyces cerevisiae strains (XG1, XG2, XG3, XG4 and XG5) and their influence on the chemical composition and sensory properties of Treixadura wines were evaluated. The inoculated strains have successfully led and completed the fermentations. Wines obtained from different yeasts showed significant differences in total and volatile acidity. Regarding volatile compounds, significant differences among wines were found for acetates, ethyl esters, acetoin, 1-hexanol, and fatty acids. Wines from spontaneous fermentation and those made with yeasts XG3 and XG4 were clearly separated through principal component analysis. Chemical composition influenced sensory properties of wines, especially at the olfactory level. Different connotations of fruity notes predominated depending on the strain. The wine from strain XG4 was the most appreciated by panelists. Our results confirmed that autochthonous S. cerevisiae strains are useful tools in winemaking because they allow obtaining singular wines from a given variety.

Resumen: 
BACKGROUND: Yeasts responsible for fermentation have an important repercussion on wine quality. This study presents the influence of two autochthonous strains of Saccharomyces cerevisiae (XG1 and XG3), a commercial yeast (QA23) and spontaneous fermentation on the chemical and sensory properties of wines from Godello and Albariño.

RESULTS: All the yeasts showed normal fermentative kinetics and were able to lead fermentations; therefore, they were responsible for wine chemical and sensory characteristics. Significant differences were found at the chemical level depending on yeast strain and variety. Albariño wines from XG1 and XG3 presented low total acidity and glycerol content. Godello wines from QA23 had higher total acidity but lower alcohol content than those from XG1, XG3 and spontaneous fermentation. QA23 wines presented a greater amount of higher alcohols and 2-phenylethanol for both grapevine cultivars, whereas XG3 and spontaneous fermentations yielded wines with a higher concentration of esters, mainly ethyl lactate, and fatty acids. These differences were detected at the sensory level; thus, Albariño made with XG3 and Godello from spontaneous fermentation were the most appreciated wines.

CONCLUSION: XG3, an autochthonous strain of S. cerevisiae, constitutes a useful tool to elaborate wines with singular characteristics.

Resumen:
The main grapevine germplasm bank of Vitis spp. at the Estación de Viticultura y Enología de Galicia in northwestern Spain includes 272 accessions. Eight SSRs differentiated 66 different genotypes, with 27 groups of synonyms and six homonyms. Brancellao Blanco (white berries) could not be differentiated from Brancellao (black berries). Eleven genotypes had not been previously described. The eight SSRs used in this study confirmed the existence of two groups of cultivars from Galicia: the Caíño group in the west and the Merenzao group in the east.

Acceso a la publicación: http://www.ajevonline.org

Resumen:
Aims : This work contributes to the knowledge of the genetic diversity of Vitis vinifera L. with the characterization of the non-referenced cultivar ‘Albilla’ by ampelographic description and molecular markers. This will be useful for the preservation, identification and propagation of this cultivar in the future.

Methods and results : Six microsatellites (SSRs), 55 OIV (International Organisation of Vine and Wine) morphological descriptors and 45 phylometric traits were evaluated in two accessions of ‘Albilla’ preserved in the Germplasm Bank of EVEGA (Estación de Viticultura e Enoloxía de Galicia), Xunta de Galicia. Additionally, we set out to determine whether this cultivar was distinct from the yet uncharacterized ‘Albillo’ cultivars found in the Canary Islands. These methods allowed us to describe the cultivar known as ‘Albilla’ and to compare it with other homonym cultivars.

Conclusions : The ‘Albilla’ cultivar is different from other genotypes denominated ‘Albillo’ and any other genotype described until now. This may indicate that it could be an autochthonous cultivar from Galicia.

Significance and impact of the study : The characterization of cultivars is still necessary in order to identify any homonyms or synonyms, develop measures for their conservation (germplasm collection) and evaluate their potential for producing quality wines.

Acceso a la publicación: http://www. jisvv.com

Resumen:
Este trabajo presenta los resultados de dos ensayos de riego realizados durante la campaña 2012 sobre la variedad autóctona gallega Godello en dos Denominaciones de Origen, Ribeiro y Valdeorras. El ensayo del Ribeiro consistió en un testigo de secano y un riego al 70 % de la ETo, mientras que en el ensayo de Valdeorras se aportó una dosis fija de 2 l día^-1 planta^-1 en los tratamientos de riego por goteo aéreo y subsuperficial, contándose con un testigo en secano. Se monitorizó el estado hídrico de las plantas en ambos ensayos y se llevaron a cabo medidas de conductancia estomática y actividad de la clorofila a. Asimismo se tomaron datos de producción y se analizaron mostos y vinos de todos los tratamientos considerados. No se observaron diferencias significativas en cuanto a parámetros de producción en ninguna de las parcelas; por ejemplo en Ribeiro, se obtuvieron 4,91 y 4,89 kg planta^-1 en secano y riego, respectivamente. En Valdeorras, 2,89 kg planta^-1 en secano, 2,91 y 3,5 kg planta^-1 en riego por goteo aéreo y subsuperficial, respectivamente. Se observó un ligero retraso en la maduración de los tratamientos de riego frente al secano; los mostos de las plantas regadas presentaron un menor pH, una mayor acidez y un menor contenido en azúcares. En los vinos se observó la misma tendencia.

Web de la revista: http://www.sjruraldevelopment.org/es/

Enlace de la revista para descargar texto completo: http://www.sjruraldevelopment.org/es/journal/309/respuesta-fisiologica-y-agronomica-de-la-variedad-godello-a-diferentes-sistemas-de-riego-en-dos-denominaciones-de-origen-gallegas/

Resumen:
Durante el año 2012 se ha puesto en marcha el proyecto “Influencia de diferentes prácticas culturales en el estado hídrico de viñedos del Noroeste de España: valoración agronómica y económica”, conjunto entre la Estación de Viticultura y Enología de Galicia y el equipo de investigación en Fertirrigación y Necesidades Hídricas de los Cultivos (GI-1716-Proepla) de la Universidade de Santiago de Compostela para conocer la influencia sobre el estado hídrico de los viñedos del Noroeste de España tanto del riego como del uso de cubiertas vegetales, éstas como sistema de mantenimiento del suelo, y las repercusiones de ambas prácticas en la producción y la calidad de la uva. Este proyecto cuenta con financiación del Instituto Nacional de Investigación y Tecnología Agraria (INIA) y fondos FEDER así como con la colaboración de diferentes bodegas de las cinco denominaciones de origen gallegas. Se trata de un proyecto a tres años que finalizará en noviembre de 2014. En el presente texto se describe la problemática que ha inducido al planteamiento de este proyecto, los objetivos, y las acciones a realizar.

Web de la revista: http://www.sech.info/

Resumen:
Las prácticas culturales en la vid son fundamentales para poder adaptar el potencial de producción a las necesidades del mercado, favoreciendo la mecanización de los viñedos sin mermar la calidad de los vinos obtenidos. En este estudio se han comparado las respuestas agronómicas y enológicas del Albariño en los dos sistemas de conducción más habituales en los viñedos comerciales de su área de mayor producción (Denominación de Origen Rías Baixas) en España. Para ello se seleccionaron dos viñedos comerciales dentro de la D.O. Rías Baixas en los que las plantas se encontraban conducidas tanto en espaldera como en parra. Aleatoriamente se escogieron 16 plantas por sistema (32 plantas por viñedo) sobre las que se realizaron medidas de parámetros agronómicos incluyendo el número de racimos por planta, peso del racimo y producción por planta. Se analizaron también los mostos y los vinos.

Web de la revista: http://www.interempresas.net/Vitivinicola/Articulos/107118-Respuestas-agronomica-enologica-variedad-Albarino-bajo-dos-sistemas-conduccion-principal.html

Resumen:
El riego se está extendiendo en la Denominación de Origen (DO) Rías Baixas para evitar descensos en la producción de uva causados por las características climáticas de cada año; si bien, los viticultores necesitan conocer cuándo, cuánto y cómo regar ya que no suelen disponer de esta información y un uso inadecuado del riego puede generar problemas de desequilibrios entre los desarrollos vegetativo y productivo del viñedo. Por otra parte, el exceso de vigor se puede limitar con el empleo de cubiertas vegetales como mantenimiento del suelo lo que, además, tiene ventajas medioambientales como el control de la erosión. Por ello que se ha puesto en marcha el proyecto ‘Influencia de diferentes prácticas culturales en el estado hídrico de viñedos del Noroeste de España: valoración agronómica y económica’, conjunto entre la Estación de Viticultura y Enología de Galicia y el equipo de investigación en Fertirrigación y Necesidades Hídricas de los Cultivos (GI-1716-Proepla) de la Universidade de Santiago de Compostela con el fin de conocer la influencia sobre el estado hídrico de los viñedos del Noroeste de España tanto del riego como del uso de cubiertas vegetales y las repercusiones de ambas prácticas en la producción y la calidad de la uva.

Web de la revista: http://www.interempresas.net/Vitivinicola/Articulos/107182-Estado-hidrico-de-vinedos-del-noroeste-de-Espana-valoracion-agronomica-y-economica.html

Resumen:
El color de un vino nos puede dar una idea de su edad, su estado de conservación o si presenta algún tipo de defecto. Son muchas las moléculas relacionadas con el color de un vino, siendo las más importantes los compuestos fenólicos como antocianos y taninos. Con el tiempo, el vino pierde su color; por eso, es fundamental la combinación que se produce entre estas moléculas ya que consiguen que se mantenga estable. El objetivo de este trabajo es el análisis de los parámetros generales de color y la determinación de compuestos fenólicos en vinos de dos variedades tintas autóctonas gallegas Sousón y Brancellao, teniendo en cuenta dos tipos de tratamiento de riego durante la campaña de 2012. Se observó que la intensidad colorante es mayor en los vinos obtenidos en el tratamiento de riego, al igual que la composición fenólica, siendo significativas las diferencias entre tratamientos para la variedad Sousón. En general, el riego ha ejercido un efecto positivo sobre la concentración de compuestos fenólicos, muy importante a la hora de su envejecimiento en barrica.

Web de la revista: http://quatrebcn.es/enoviticultura-no-24/

Resumen:
Aims: The aim of this study was to investigate whether grapevine variety and must characteristics influence the diversity of Saccharomyces strains and their prevalence during spontaneous fermentations. Methods and results: Musts from different grapevine varieties, all of them autochthonous from Galicia, were used to perform spontaneous fermentations. Yeasts were isolated from the must and at the beginning, in the middle and at the end of fermentations. Those yeasts identified as Saccharomyces were characterized at the strain level by analysis of mtDNA-RFLP. The results showed a low diversity of Saccharomyces strains, which was related to must sugar content and total acidity. Moreover, from a total of 44 different Saccharomyces strains, only eleven of them appeared at frequencies higher than 20% and were able to lead fermentations. A significant correlation between yeast strains and must acidity was observed, with the predominance of certain strains at high acidity values. Conclusions: Must characteristics, such as sugar content and acidity, influence the Saccharomyces strains diversity and the leader strains during fermentation. Significance and Impact of the Study: These results showed the adaptation of certain Saccharomyces strains to must with specific characteristics; this may be considered by winemakers for yeast inocula selection. Our findings have special relevance because this is the first study carried out in Galicia dealing with the influence of must properties on yeast strains that control fermentations.

Resumen:
The grapevine germplasm bank from Estación de Viticultura e Enoloxía de Galicia contains 110 accessions collected from more than 100-year-old grapevines from northwestern Spain. We identified 60 different genotypes (among hich ‘Pinot Noir’ and ‘Shyrah’ were included as references) with 32 polymorphic microsatellites (SSRs), 21 of which were unlinked SSRs and without null alleles, which were used to detect genetic structure. We found four reconstructed populations that were highly differentiated by analysis of molecular variance (18.3%): (i) western Galician group (‘Ca´ın˜ o Bravo’); (ii) eastern Galician group (‘Merenzao’); (iii) Castilian group (‘Garnacha’) and (iv) southern Spanish group (‘Moscatel’). The greatest genetic differentiation was found between the western Galician/eastern Galician groups and the southern Spanish/Castilian groups, with Fst>0.13. Western and eastern Galician groups contained most of the ancient Galician cultivars (86%) and included ancestors from central Europe, such as ‘Pinot Noir’ and ‘Shyrah’ in the western Galician group and the introgressant ‘Merenzao’ (French ‘Trousseau’) in the eastern Galician group; the Castilian and southern Spain groups included traditional cultivars from central and southern Spanish and suggest a further introduction of those cultivars in northwestern plantations. Genetic structure corresponded with East-to-West geographical differentiation in the northern Iberian Peninsula, following the old path to Santiago de Compostela from France, with the southern Spanish and Castilian groups in the East (Castilian plateau and southern Spain), the eastern Galician group and the western Galician group in the West. Five new relationships were discovered: ‘Ca´ın˜ o Bravo’/‘Ca´ın˜ o Longo2’, ‘Albar´ın Tinto’/‘Torrontés1’, ‘Treixadura’/‘Treixadura Francesa’, ‘Moscatel’/‘Moscatel de Bago Miu´ do’ and ‘Moscatel’/‘Moscatel de Hamburgo’, indicating that hybridisation and further selection by growers have been the origin of most of the genetic diversity found in northwestern Spain.

Acceso a la publicación: http://www.wiley.com

Resumen: 
En este trabajo se ha evaluado la capacidad de implantación de levaduras autóctonas y comerciales en la fermentación de mosto y bagazo de distintas variedades de uva de Galicia. Para ello, se tomaron muestras en distintas fases del proceso fermentativo y, de cada una de ellas, se aislaron un número representativo de colonias. Las levaduras identificadas como Saccharomyces cerevisiae fueron caracterizadas a nivel de cepa mediante análisis de los mtDNA-RFLPs. Los resultados mostraron que todas las cepas inoculadas en las fermentaciones de mostos de variedades blancas se implantaron en el proceso. Sin embargo, con la variedad tinta Mencía, las levaduras autóctonas actuaron en codominacia con la cepa comercial Excellence XR, la cual sí fue dominante en las fermentaciones donde se inoculó. Finalmente, la levadura Vitilevure KD se impuso en las fermentaciones de bagazo de Treixadura y Godello; sin embargo, la cepa BDX no mostró una buena adaptación al bagazo de Albariño, en el cual la levadura autóctona XG3 se implantó satisfactoriamente en casi todas las fermentaciones.

Resumen:
Los estudios sobre los efectos del riego en viñedos gallegos son muy escasos y apenas se conoce la respuesta agronómica y enológica de las variedades tradicionales gallegas a un aporte suplementario de agua. El cambio climático ha provocado un interés creciente por conocer si el riego puede afectar a la calidad de los vinos blancos gallegos. Es en este contexto que el equipo investigador de la Estación de Viticultura y Enología de Galicia (Evega) y el Grupo de Investigación GI-1716 ‘Proyectos y Planificación’ de la Universidad de Santiago de Compostela ha puesto en marcha un proyecto a tres años para conocer el efecto de varias estrategias de irrigación sobre la producción y calidad de uva en viñedos gallegos. El proyecto, financiado por el INIA, con un 70% de fondos FEDER, lleva por título ‘Influencia de diferentes prácticas culturales en el estado hídrico de viñedos del noroeste de España: valoración agronómica y económica’. En este artículo, se presentan los resultados correspondientes al primer año de experiencias en la Denominación de Origen Ribeiro, sobre tres variedades blancas de cultivo tradicional en Galicia: la Treixadura, el Godello y el Albariño.

Web de la revista: http://www.interempresas.net/Vitivinicola/Articulos/100471-Efectos-riego-tres-variedades-blancas-autoctonas-gallegas-%28Treixadura-Godello-Albarino%29-D.html

Resumen: 
Inoculation of active dry yeasts during the wine-making process has become a common practice in most wine-producing regions; this practice may aVect the diversity of the indigenous population of Saccharomyces cerevisiae in the winery. The aim of this work was to study the incidence of commercial yeasts in the experimental winery of Estación de Viticultura e Enoloxía de Galicia (EVEGA) and their ability to lead spontaneous fermentations. To do this, 64 spontaneous fermentations were carried out in the experimental cellar of EVEGA over a period of 7 years. Samples were taken from must and at the beginning, vigorous and Wnal stages of fermentation. A representative number of yeast colonies was isolated from each sample. S. cerevisiae strains were characterised by analysis of mitochondrial DNA restriction patterns. The results showed that although more than 40 different strains of S. cerevisiae were identiWed, only 10 were found as the dominant strain or in codominance with other strains in spontaneous fermentations. The genetic proWles (mtDNARFLPs) of eight of these strains were similar to those of diVerent commercial yeasts that had been previously used in the EVEGA cellar. The remaining two strains were autochthonous ones that were able to reach implantation frequencies as high of those of commercial yeasts. These results clearly indicated that commercial wine yeasts were perfectly adapted to survive in EVEGA cellar conditions, and they successfully competed with the indigenous strains of S. cerevisiae, even during spontaneous fermentations. On the other hand, autochthonous dominant strains that presented desirable oenological traits could be of interest to preserve wine typicity.

Resumen:
The fermentative ability of five Saccharomyces cerevisiae strains and their influence on the aroma and sensory properties of wine from Treixadura were evaluated to determine the most suitable yeast that produces a high quality wine from this grapevine variety. The results indicated that all strains, except T2, were able to lead the vinification process and have good fermentative powers. The chemical composition of wines obtained with resident cellar yeasts consisted of a significant amount of glycerol, a compound that contributes to the structure and smoothness in taste of the wine. In addition, these strains were good producers of acetates, ethyl esters and fatty acids, compounds that positively influence wine aroma. Compounds with a direct contribution to the aroma of Treixadura wines (Odour Activity Value [1) included 2-methyl-1-butanol, 3-methyl-1-butanol, 2-phenylethanol, isoamyl and ethyl acetate and the ethyl esters, ethyl butyrate, ethyl hexanoate, ethyl octanoate and ethyl decanoate. Sensory analysis supported the fact that cellar strains produced more fruity and floral wines than commercial or spontaneous fermentations. We conclude that resident cellar yeasts enhanced sensory quality of wines from Treixadura.

Resumen:
Higher alcohols, ethyl esters, acetates, and volatile acids were determined by gas chromatography in wines made from two ecotype cultivars of Brancellao grapes, named Brancellao and Albarello, over two consecutive vintages. The wines were also sensorially evaluated by seven professional panellists who were asked to rank the intensity of several attributes using a scale of 0–5 (0 = not perceivable and 5 very strong intensity). 28 volatile compounds were identified and the results showed that the most of them are common to both ecotypes and that the differences are only quantitative. In 2005 and 2006 vintages, 15 and 17 volatile compounds, respectively, showed significant differences between both cultivars, whereas methanol, 1-butanol, ethyl acetate, ethyl decanoate and ethyl myristate were the compounds that did not present significant differences of concentration. The OAV’s values of the majority of the volatile compounds identified are higher in Brancellao wines, indicating a stronger bouquet and greater complexity of the winesmade from this ecotype cultivar. In the nose phase, a wider aromatic complexity,a greater intensity of the fruity notes and an important contribution of spicy, balsamic and aromatic herbaromas were observed. The aromatic profile of Albarello wine is notable for its animal and toasted nuances. Knowledge of these results will contribute to a better understanding of this red cultivar.

Acceso a la publicación: http://www.journals.elsevier.com/journal-of-food-omposition-and-analysis/

Resumen:
The grapevine germplasm bank EVEGA contains 135 accessions of 15 Galician cultivars. Analysis with 33 polymorphic microsatellites (SSRs) indicate that Albariño and Loureira could be related to the Caíño group in western Galicia, Spain. Likelihood ratios support the hypothesis of significant parentage relationship between Albariño and Caíño Bravo as parents of Caíño Blanco. Loureira shared alleles for each locus with Caíño Bravo, indicating close relationship by hybridization. Caíño Bravo was related directly with four cultivars (Caíño Blanco, Caíño Longo, Castañal, and Loureira) and with two others (Caíño Redondo1 and Sousón), with which it shared 32 of 33 loci, indicating that it could be the origin of this lineage, as the key cultivar of the Caíño group.

Acceso a la publicación: http://www.ajevonline.org

Resumen:
The grapevine gemoplasm bank in the “Estación de Viticultura y Enología de Galicia. Xunta de Galicia”, holds fifteen grapevine cultivars with a total of 98 accesions: ‘Brancellao’, ‘Albarello, ‘Caíño Astureses’, Caíño Bravo’, Caíño Blanco’, Caíño Gordo’, Albarín Negro’, Caíño Longo’, Caíño Redondo’, ‘Castañal’, Mencía’, ‘Merenzao’, Mouratón’, Sousón’, and ‘Verdello’. Cultivars ‘Syrah’ and ‘Pinot Noir’ were included as references. Two diferente lineages were detected, one originating in ‘Caíño Astureses’ and the other in ‘Merenzao’, synonymy of the French aultivar ‘Trusseau’. Cultivars from Northwestern Spain derivedfrom both of these cultivars by hybridization and selected genotypes that had adapted to local climatic conditions and became fixed by cuttings, explaining the domestication processo f these grapevine cultivars. Both lineages differed in allelic frecuencies and were distributed differently in Northwestern Spain., the first lineage in the West and the second, related with the French cultivar ?Trousseau’, in the east. ‘Caíño Astureses’ was the most frecuent genotype related by hybridization, indicating the importance that this cultivar had in the origino f grapevines in Galicia. In addition a total of 13 different genotypes were identified. The identity of ‘Brancellao’ and ‘Albarello’ was confirmed by ssr-MARKERS. Other two synonyms were ‘Caíño Astureses’ and ‘Caíño Bravo’, and ‘Caíño Gordo’ and ‘Albarín Negro’, Caíño Redondo’ showod two diferente genotypes, one related to ‘Caíño Astureses’ and the other to ‘Merenzao’. Two cultivars included in the collection from EVEGA were not reported previously, Verdello’ and ‘Caíño Longo’.

Acceso a la publicación: http://www. jisvv.com

Resumen:
El empleo de variedades autóctonas está siendo considerado, en la región gallega, como una posible vía para la obtención de vinos de marcada tipicidad que los haga competitivos en un mercado cada vez más exigente. En este sentido, uno de los parámetros básicos para la obtención de un vino de calidad es partir de uvas con grado de maduración adecuado. Por ello, con la finalidad de determinar la incidencia del genotipo en la fecha más adecuada para la vendimia, se estudió la evolución de la maduración y su variación en función de variabilidad intravarietal en mosto de cinco cultivares tintos de cultivo tradicional en la región, mediante el análisis de parámetros químicos básicos.

Los resultados muestran como fecha de vendimia para el cultivar Merenzao, principios del mes de septiembre, para Brancellao y Mouratón mediados y para Sousón y Ferrón finales de dicho mes. Por otra parte, se ha puesto de manifiesto la posibilidad de encontrar, en la variabilidad intravarietal genotipos cuyas características permiten adelantar la fecha de vendimia, o la obtención cuyas características determinan la obtención de vinos más equilibrados y, por tanto, de mayor calidad.

Resumen:
The accumulation of anthocyanins in grape skinand their extractability evolution along ripening were evaluated in Galician red cultivars during 2005 and 2006 harvests. Seed tannin maturity and total phenolic compounds were also investigated through seed phenolic maturity and total polyphenol indexes, respectively. Furthermore, statistical correlations between phenolic composition and classical parameters were established through ripening in order to find a more rapid and simpler methodology, which permits to predict the maximum anthocyanin concentration in red wines. So, statistical correlation was found for total polyphenol index and total acidity in all the cultivars studied, while the greatest anthocyanin accumulation can only be estimated from titrable acidity for the most colours cultivars. The cultivars studied were caractericed on the basis of their phenolic composition (anthocyanins proanthocyanidins, catechins) in order to know their oenological potential. Principal component analysis allowed a first approximation to the characterisation and the differentiation of the red cultivars studied on the base of their phenolic composition in vintage, as measured by spectrophotometric methodologies. Simple phenolic determinations which can be carried out in winery, provided fundamental information for the oenologist during the planning and management of pressing and maceration processes.

Acceso a la publicación: http://www.journals.elsevier.com/journal-of-food-omposition-and-analysis/

Resumen: This work describes the influence of yeast population on the chemical characteristics of wine obtained by spontaneous and inoculated fermentation of must from Vitis vinifera Lado, a minor white grapevine autochthonous to Galicia (NW Spain). The study was carried out for two consecutive years. The results showed that musts derived from Lado presented a high acidity though the potential alcohol level was acceptable. The genetic diversity of S. cerevisiae strains isolated from spontaneous fermentations was low, probably due to must characteristics, although these did not interfere with the implantation of the commercial strains used. Analyses showed that the wines subsequently produced had high alcoholic levels and very high acidities (pH 3.0) as was expected from must composition. Wines obtained from spontaneous fermentations had a lower alcohol content but higher total acidity than those from inoculated fermentations. Monovarietal wines produced from Lado were poorly evaluated in sensorial tests because of their unbalanced structure and sourness; however, when they were mixed with other autochthonous white varieties with less acidity, the resulting wines were well accepted.

Resumen:
Genetic diversity of wine Saccharomyces cerevisiae strains involved in spontaneous fermentations was studied by analysis of mitochondrial DNA restriction patterns. Yeasts were isolated at different stages of fermentations with must from three different white grapevine varieties, Albarin˜ o, Godello and Treixadura, which are autochthonous from Galicia. Nineteen different patterns out of a total of 446 strains analysed were identified, but only a few of them appeared at high frequency and therefore were able to lead the fermentation process. Some strains were common to all fermentations; however, most of them were a minority being only found at low frequency for one or two specific grape varieties. The dominant strain was different for each variety except in one case, suggesting that some strains are better adapted to certain must conditions.