29 research outputs found
Grapevine flower estimation by applying artificial vision techniques on images with uncontrolled scene and multi-model analysis
New technologies in precision viticulture are increasingly being used to improve grape quality. One of the main challenges being faced by the scientific community in viticulture is early yield prediction. Within this framework, flowering as well as fruit set assessment is of special interest since these two physiological processes highly influence grapevine yield. In addition, an accurate fruit set evaluation can only be performed by means of flower counting. Herein a new methodology for segmenting inflorescence grapevine flowers in digital images is presented. This approach, based on mathematical morphology and pyramidal decomposition, constitutes an outstanding advance with respect to other previous approaches since it can be applied on images with uncontrolled background. The algorithm was tested on 40 images of 4 different Vitis vinifera L. varieties, and resulted in high performance. Specifically, values for Precision and Recall were 83.38% and 85.01%, respectively. Additionally, this paper also proposes a comprehensive study on models for estimating actual flower number per inflorescence. Results and conclusions that are developed in the literature and treated herewith are also clarified. Furthermore, the use of non-linear models as a promising alternative to previously-proposed linear models is likewise suggested in this study. © 2015 Elsevier B.V
Solar ultraviolet radiation is necessary to enhance grapevine fruit ripening transcriptional and phenolic responses
Background: Ultraviolet (UV) radiation modulates secondary metabolism in the skin of Vitis vinifera L. berries, which affects the final composition of both grapes and wines. The expression of several phenylpropanoid biosynthesis-related genes is regulated by UV radiation in grape berries. However, the complete portion of transcriptome and ripening processes influenced by solar UV radiation in grapes remains unknown.Results: Whole genome arrays were used to identify the berry skin transcriptome modulated by the UV radiation received naturally in a mid-altitude Tempranillo vineyard. UV radiation-blocking and transmitting filters were used to generate the experimental conditions. The expression of 121 genes was significantly altered by solar UV radiation. Functional enrichment analysis of altered transcripts mainly pointed out that secondary metabolism-related transcripts were induced by UV radiation including VvFLS1, VvGT5 and VvGT6 flavonol biosynthetic genes and monoterpenoid biosynthetic genes. Berry skin phenolic composition was also analysed to search for correlation with gene expression changes and UV-increased flavonols accumulation was the most evident impact. Among regulatory genes, novel UV radiation-responsive transcription factors including VvMYB24 and three bHLH, together with known grapevine UV-responsive genes such as VvMYBF1, were identified. A transcriptomic meta-analysis revealed that genes up-regulated by UV radiation in the berry skin were also enriched in homologs of Arabidopsis UVR8 UV-B photoreceptor-dependent UV-B -responsive genes. Indeed, a search of the grapevine reference genomic sequence identified UV-B signalling pathway homologs and among them, VvHY5-1, VvHY5-2 and VvRUP were up-regulated by UV radiation in the berry skin.Conclusions: Results suggest that the UV-B radiation-specific signalling pathway is activated in the skin of grapes grown at mid-altitudes. The biosynthesis and accumulation of secondary metabolites, which are appreciated in winemaking and potentially confer cross-tolerance, were almost specifically triggered. This draws attention to viticultural practices that increase solar UV radiation on vineyards as they may improve grape features. © 2014 Carbonell-Bejerano et al.; licensee BioMed Central Ltd
Effects of timing defoliation on wine composition of Grenache in Rioja
4 páginas, 2 tablas, 4 figuras.- Trabajo presentado al Congreso celebrado en Logroño (España) entre los dÃas 25 y 30 de junio de 2006.[EN] The effects of timing defoliation at fruit set and veraison on wine composition of Grenache was investigated. Grenache bush vines (Vitis vinifera L.) were grown under field conditions in Rioja appellation (Spain). Leaf removal has not modified significantly berry weight, cluster weight and fruit yield per vine. Alcohol content, pH, titratable acidity, tartaric acid concentration and total polyphenols index of wine were unaffected by partial defoliation. Early leaf removal, at fruit set, decreased the malic acid content in the wine. Colour intensity was significantly higher in Grenache wine from leaf removal treatment at fruit set.[ES] En este trabajo se han estudiado los efectos de la época de deshojado sobre las caracterÃsticas fÃsico-quÃmicas de los vinos de la variedad Garnacha tinta (Vitis vinifera L.) en Rioja. En un viñedo adulto de Garnacha conducido en vaso se han observado los efectos de tres tratamientos de deshojado: deshojado temprano (en cuajado), deshojado tardÃo (en envero) y control (no deshojado). Ningún tratamiento de deshojado ha modificado significativamente el peso de la baya, ni el peso del racimo, ni la producción de uva por cepa. El deshojado no modificó significativamente el grado alcohólico de los vinos, ni el pH, ni la acidez total ni la concentración de ácido tartárico ni el Ãndice de polifenoles totales. Los vinos procedentes del deshojado temprano (en cuajado) poseÃan una intensidad colorante significativamente mayor y una concentración de ácido málico menor.Peer reviewe
Influencia de la época del deshojado en el comportamiento vitÃcola y caracterÃsticas sensoriales de las bayas de los vinos de la variedad Garnacha
4 hojas, 2 tablas, 4 figuras -- Trabajo presentado en el V Foro Mundial del Vino, celebrado en Logroño (España) entre el 28 y el 30 de marzo de 2006.El deshojado es una técnica de cultivo muy potente para modificar la luz recibida por los frutos. La exposición de los racimos influye sobre la composición de las uvas y las caracterÃsticas organolépticas de los vinos. En este trabajo se han estudiado los efectos de la época de deshojado en el comportamiento vitÃcola y caracterÃsticas organolépticas de las bayas y de los vinos en de la variedad Garnacha (Vitis vinifera L.) en la DOCa Rioja en la añada 2005. En un viñedo adulto de Garnacha conducido en vaso se han observado los efectos de tres tratamientos de deshojado: deshojado temprano (en cuajado), deshojado tardÃo (en envero) y control (no deshojado). Ningún tratamiento de deshojado ha modificado significativamente el peso del racimo, ni la producción de uva por cepa. No se han observado diferencias significativas en cuanto al desarrollo vegetativo. El deshojado indujo una madurez de los hollejos significativamente superior respecto al control. El deshojado temprano mejoró significativamente la madurez global de la baya. También los vinos procedentes del deshojado temprano (en cuajado) alcanzaron de forma significativa la mayor valoración organoléptica.Peer reviewe
Effects of timing defoliation on wine sensory characteristics of Grenache in Rioja
4 páginas, 1 tabla, 1 figura -- Trabajo presentado en el Congreso celebrado en Logroño (España) entre el 25 y el 30 de junio de 2006.[EN] The effects of timing defoliation at fruit set and veraison on wine sensory properties of Grenache was investigated. Grenache bush vines (Vitis vinifera L.) were grown under field conditions in Rioja appellation (Spain). The defoliation has modified significantly the sensory properties of Grenache wines. Intensity of colour and complexity of the aroma were significantly higher in Grenache wine from leaf removal treatment at fruit set. The no defoliation wines were rated significantly higher in floral aroma. Garnacha wine from early defoliation was the most preferred in global value.[ES] En este articulo se han estudiado los efectos de la época de deshojado sobre las caracterÃsticas organolépticas de los vinos de la variedad Garnacha tinta (Vitis vinifera L.) en Rioja. En un viñedo adulto de Garnacha conducido en vaso se han observado los efectos de tres tratamientos de deshojado: deshojado temprano (en cuajado), deshojado tardÃo (en envero) y control (no deshojado). La época del deshojado ha modificado significativamente las caracterÃsticas organolépticas de los vinos de Garnacha tanto el color como el aroma. Los vinos procedentes del deshojado realizado en el cuajado resultaron los vinos con una intensidad de color significativamente mayor. También la complejidad del aroma fue significativamente más importante en los vinos del deshojado temprano, mientras los aromas florales fueron superiores en los vinos del viñedo no deshojado. Los resultados del análisis sensorial, han mostrado que los vinos procedentes del deshojado realizado en cuajado han resultado los más valorados globalmente.Peer reviewe
Factores infecciosos de variación del recuento celular de la leche de oveja
Los patógenos desencadenantes de las infecciones mamarias se han agrupado clásicamente en patógenos mayores (estafilococos coagulasa-positivos, estreptococos, enterobacterias, Pasteurella spp., micoplasmas, etc.) y menores (estafilococos coagulasa-negativos, micrococos, levaduras, etc.). En la oveja lechera, el grupo etiológico más prevalente viene representado por los estafilococos y, especialmente, por los estafilococos coagulasa-negativos. Analizada la relación entre las principales especies de patógenos mamarios y la respuesta celular derivada, se demuestran mayores recuentos celulares y, en consecuencia, una mayor patogenicidad, en aquellas especies sensibles a la novobiocina con relación a las que son resistentes a este antibiótico. El análisis de las diferencias en la respuesta celular obliga a una reclasificación de la patogenicidad de algunas especies de estafilococos coagulasa-negativos, pues su consideración como patógenos menores resulta inadecuada actualmente. La respuesta celular vinculada a la infección con el virus Maedi-Visna es también analizada, concluyendo que su efecto sobre el recuento celular de la leche, aunque puede ser significativo, es de menor importancia que el debido a la infección bacteriana
Factores infecciosos de variación del recuento celular de la leche de oveja
Los patógenos desencadenantes de las infecciones mamarias se han agrupado clásicamente en patógenos mayores (estafilococos coagulasa-positivos, estreptococos, enterobacterias, Pasteurella spp., micoplasmas, etc.) y menores (estafilococos coagulasa-negativos, micrococos, levaduras, etc.). En la oveja lechera, el grupo etiológico más prevalente viene representado por los estafilococos y, especialmente, por los estafilococos coagulasa-negativos. Analizada la relación entre las principales especies de patógenos mamarios y la respuesta celular derivada, se demuestran mayores recuentos celulares y, en consecuencia, una mayor patogenicidad, en aquellas especies sensibles a la novobiocina con relación a las que son resistentes a este antibiótico. El análisis de las diferencias en la respuesta celular obliga a una reclasificación de la patogenicidad de algunas especies de estafilococos coagulasa-negativos, pues su consideración como patógenos menores resulta inadecuada actualmente. La respuesta celular vinculada a la infección con el virus Maedi-Visna es también analizada, concluyendo que su efecto sobre el recuento celular de la leche, aunque puede ser significativo, es de menor importancia que el debido a la infección bacteriana
Differences in the rate of coloration in tomato fruit
The evolution of fruit color of twelve tomato (Lycopersicon esculentum Mill.) cultivars during ripening was evaluated. Final color of each of the cultivars was determined by calculating its fresh tomato color index (TCIf). Luminosity (L*), red-green component (a*), a*/b* ratio, hue angle (h*), dominant wavelength (DW) and fresh tomato color index (TCIf) were the parameters that best differentiated the ripening stages of tomato fruit. Dominant wavelength and purity of excitation were correlated with a* and b*. Fresh tomato color index (TCIf) was related to the luminosity (L*) and yellow-blue component (b*)
Mechanical Crop Thinning and Early Defoliation as Novel Tools for Yield Management in VSP Grapevines
Cost-effective yield management is becoming fundamental in modern viticulture in order to meet the existing yield regulations in many parts of the world and to improve grape quality. The evaluation of mechanically performed early defoliation and crop thinning, aiming at yield management, and their effects on the vegetative growth, yield components, grape and wine composition, against a non-defoliated, not-thinned control, and manual treatments are presented. Manual and mechanical early defoliation and crop thinning were conducted at pre-bloom and veraison, respectively, on Tempranillo (Vitis vinifera L.) VSP grapevines in season 2009. A detailed description of the mechanical settings and adjustments, based on preliminary results from previous seasons, for the correct performance of both techniques is provided. Whilst total leaf area remained unaltered, yield was drastically reduced by both practices (38-40%), hence the leaf-to-fruit ratio also enhanced with respect to control vines. Cluster weight, berry number, as well as cluster compactness and Botrytis incidence were also reduced in yield regulated vines, but berry weight tended to increase in mechanically thinned vines and remained unaffected in the early defoliated plants. Berry soluble solids, anthocyanins and total phenols, as well as wine alcohol, color density and total phenol index were generally higher in mechanically early defoliated vines. Effective yield control and fruit quality improvement in VSP grapevines may be accomplished mechanically.Peer Reviewe