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- ItemOpen AccessOptimización de los tratamientos fitosanitarios en plantaciones frutales(Universitat Politècnica de Catalunya, 1990-07-12) Planas de Martí, SantiagoEl estudio ha sido realizado en la región frutícola de Lleida (Catalunya), noreste de España, dedicada especialmente al cultivo intensivo de fruta de pepita (peral y manzano) y de hueso (melocotonero). Se trata de una zona extensa, innovadora y de larga experiencia frutícola. El trabajo comprende 40 ensayos ejecutados en plantaciones comerciales de perales y manza-nos, formadas en palmeta regular. El objetivo principal es valorar la influencia del volumen de caldo pulverizado y la dosis unitaria (i.a./ha) sobre la eficacia del tratamiento. Los tratamientos han sido realizados mediante pulverizadores con asistencia de aire, equipados con boquillas cónicas en el caso de aplicaciones a 1600 y 400 L/ha y con cabezales rotativos (Micron X-1) para 100 L/ha. Adicionalmente se estudia el comportamiento del ventilador y su influencia sobre la calidad de la aplicación. Se ha recurrido al análisis cuantitativo de la deposición de producto fitosanitario sobre el obje-tivo a tratar, mediante oxicloruro de cobre empleado como trazador, y a la determinación de la eficacia biocida (Abbott y Henderson-Tilton). El análisis estadístico de los resultados permite concluir que los tratamientos a 1600 y 400 L/ha consiguen resultados similares, incluso en el control de plagas de especial dificultad como Pa-nonichus ulmi y Psilla pyri. Sin embargo, los tratamientos a 100 L/ha son descartables puesto que reducen notablemente la deposición de producto sobre el objetivo a proteger. En el control de P. pyri, los tratamientos a dosis reducida (-25%) son tan eficaces como los rea-lizados a plena dosis. Sin embargo, en el control de P. ulmi, la eficacia se ve disminuida si se reduce la dosis. En general, la uniformidad de deposición es superior en las plantaciones de peral que en las de manzano debido a la mayor resistencia ejercida por la masa foliar de dicha especie. El ventilador (dirección y velocidad del flujo de aire) determina claramente la uniformidad de las deposiciones, las pérdidas al suelo y la deriva. Por otra parte, el ventilador de flujo axial presenta mejores resultados frente al ventilador de flujo radial (centrífugo). Finalmente, al objeto de limitar las pérdidas y reducir la cantidad de producto a aplicar, se propone optimizar el flujo aire/gotas para y adaptar la dosis a la dimensión de la vegetación a tratar.
- ItemOpen AccessAssessment of Recycling Tunnel Sprayers in Mediterranean Vineyards and Apple Orchards(Elsevier, 2002) Planas de Martí, Santiago; Solanelles Batlle, Francesc; Fillat, A.The use of air-assisted recycling tunnel sprayers in Mediterranean fruit orchards and vineyards was assessed by comparing the performance of two tunnel sprayer prototypes with an air-assisted axial flow sprayer. Field trials comprised measurements of spray deposit on the canopy, off-target spray losses and the biological efficacy of chemical applications. According to the results, no spray drift was measured during the applications with tunnel sprayers. Spray losses on the ground were localized mainly under the crop rows. However, the uniformity of the spray deposition on the canopy was worse than that obtained with the axial flow sprayer. It seems that this can be attributed to poor adjustment of the tunnel dimensions in relation to the crop size or to inadequate air-jet design. Tunnel sprayers may be an option to meet future environmental requirements for spray applications, so long as crop training systems change to smaller-size orchards and wall-shaped trellis vineyards.
- ItemRestrictedCenter-pivot automatization for agrochemical use(Elsevier, 2005) Palacín Roca, Jordi; Salse, José Antonio; Clua, Xavier; Arnó Satorra, Jaume; Blanco Ortiz, Ricardo; Zanuy, C.This paper presents an agrochemical application system that could be incorporated into existing irrigating center-pivots. The system consisted of a hydraulic circuit with emitters, where the dose was individually controlled with variable valve timing. This paper describes the electronic control system, designed to be modular and distributed along the pivot. The main problem solved was the determination of the emitter’s absolute displacement to generate their adequate timing control. The paper ends with the test of a low-cost implementation of the complete system under real center-pivot operation.
- ItemOpen AccessAn Electronic Control System for Pesticide Application Proportional to the Canopy Width of Tree Crops(Elsevier, 2006) Solanelles Batlle, Francesc; Escolà i Agustí, Alexandre; Planas de Martí, Santiago; Rosell Polo, Joan Ramon; Camp, Ferran; Gràcia, FelipA prototype of an electronic control system based on ultrasonic sensors and proportional solenoid valves for a proportional application to the canopy width of tree crops was mounted on an air-assisted sprayer. The sprayer flow rate adjustment was based on the relationship between the actual tree width measured by the ultrasonic sensors and the maximum tree width of the orchard. The prototype was tested in olive, pear and apple orchards to assess the system performance in different crop geometries. The spray deposit distribution was measured in comparison with conventional air-assisted applications. Metal tracers were used so that spray deposits for each treatment could be measured on the same samples, reducing sampling variability. Liquid savings of 70%, 28% and 39% in comparison to a conventional application were recorded in the olive, pear and apple orchard respectively, which resulted in lower spray deposits on the canopy but a higher ratio between the total spray deposit and the liquid sprayer output (i.e. better application efficiency). A reduction of the maximum tree width parameter in the control algorithm in the apple orchard reduced spray savings but increased spray deposition, with spray savings mainly in the middle level of the outside canopy, compared to conventional air-assisted applications.
- ItemRestrictedClimate factors affecting conception rate of high producing dairy cows in northeastern Spain(Elsevier, 2007) García Ispierto, Irina; López Gatius, Fernando; Bech Sàbat, Gregori; Santolaria Blasco, Pilar; Yániz Pérez de Albéniz, Jesús; Nogareda, Carmina; De Rensis, F.; López-Béjar, M.Summer heat stress is a main factor related to low conception rate in high producing dairy herds in warm areas worldwide. We assessed the impact of several climate variables on conception rate in high producing dairy cows in northeastern Spain by examining 10,964 inseminations. The temperature–humidity index (THI) was compared with maximum temperature in terms of its efficiency at predicting conception rate. The following data were recorded for each animal: herd, lactation number, insemination number, insemination date, inseminating bull, and AI technician along with climate variables such as mean and maximum temperatures, rainfall, mean and maximum THI for individual time points Days 7 to 1 before insemination, the day of insemination and 1, 2 and 3 days after insemination. Averages were also established for the following periods: from 7 days before insemination to the insemination day, from 3 days before insemination to the insemination day and from the insemination day to 3 days postinsemination. Based on the odds ratios, the likelihood of conception rate increased significantly by factors of 1.48, 1.47, 1.5, and 1.1 for the respective maximum THI classes <70, 71–75, 76–80, and 81–85 only on Day 3 before AI, while on the insemination day, it increased by factors of 1.73, 1.53, 1.11, and 1.3 for the respective maximum THI classes <70, 71–75, 76–80, and 81–85. In a subsequent logistic regression excluding mean and maximum THI, the effectiveness of temperature at predicting conception rate was evaluated. Although high, the fit of the second logistic regression model was slightly lower than that of the full model (P = 0.88 versus P = 0.98, respectively) and the information provided by the THI model. The likelihood of conception rate increased significantly by factors of 1.5, 1.2, 1.0, 1.0 for the respective maximum temperature classes <20, 21–25, 26–30, 31–35 8C on Day 1 after AI. The choice of the THI or temperature to monitor the farm environment would have to depend on the particular farm and situation. In our study conditions, the use of maximum temperature alone gives a new point of view regarding the information provided by the THI variables.
- ItemOpen AccessVariable rate application of plant protection products in vineyard using ultrasonic sensors(Elsevier, 2007) Gil Moya, Emilio; Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon; Planas de Martí, Santiago; Val, LuisThe changes in the shape and size of vines during the growing season require a continuous adjustment of the applied dose to optimize spray application efficiency. Target detection with ultrasonic sensors can be used to adapt the applied dose following the principles of the variable rate technology. A multi-nozzle air-blast sprayer was fitted with three ultrasonic sensors and three electro-valves, to modify the flow rate from the nozzles in real time, in relation to the variability of crop width. A constant application rate of 300 l ha−1 was compared with a variable rate application using the tree row volume principle at a 0.095 l m−3 canopy. The total flow rate sprayed by the nozzles was modified according to the variations of crop width measured by the ultrasonic sensors. On average 58% less liquid was applied compared to the constant rate application, with similar deposition on leaves with both treatments. A detailed analysis of savings indicates differences between the lower, middle and top part of the crop, in accordance with the leaf area distribution with crop height. No significant differences between treatments were detected in uniformity of liquid distribution and capability to reach the inner parts of the crop. This important reduction in spray volume could be followed by an equivalent reduction of plant protection products but further research work is needed to guarantee biological efficacy of a reduced dose.
- ItemRestrictedCombining regio- and enantioselectivity of lipases for the preparation of (R)-4-chloro-2-butanol(Wiley, 2007) Méndez, Jonh Jairo; Oromí Farrús, Mireia; Cervero, Maria; Balcells Fluvià, Mercè; Torres i Grifo, Mercè; Canela i Garayoa, RamonPreparation of 98% ee (R)-4-chloro-2-butanol was carried out by the enzymatic hydrolysis of chlorohydrin esters, using fungal resting cells and commercial enzymes. Hydrolyzes were carried out using lipases from Candida antarctica (Novozym 435®), C. rugosa, Rhizomucor miehei (Lipozyme® IM), Burkolia cepacia, and resting cells of Rhizopus oryzae and Aspergillus flavus. The influence of the enzyme, the solvent, the temperature, and the alkyl chain length on the selectivity of hydrolyzes of isomeric mixtures of chlorohydrin esters is described. Regioselectivity was higher than 95% for some of the tested lipases. Novozym 435 allowed preparation of the (R)-4-chloro-2-butanol after 15 min of reaction at 30–40°C.
- ItemRestrictedDynamics of anti-Neospora caninum antibodies during gestation in chronically infected dairy cows(Elsevier, 2007) Nogareda, Carmina; López Gatius, Fernando; Santolaria Blasco, Pilar; García Ispierto, Irina; Bech Sàbat, Gregori; Pabón, M.; Mezo, M.; Gonzalez-Warleta, M.; Castro Hermida, J. A.; Yániz Pérez de Albéniz, Jesús; Almería, S.The dynamics of antibody production against Neospora caninum during the gestation period was examined in chronically infected dairy cows. Data were obtained from 86 pregnant parous dairy cows, 21 of which had suffered abortion. The cows belonged to two herds in which a diagnosis of N. caninum infection had been previously confirmed in aborted foetuses. Pregnancy diagnosis and blood collection were performed on post-insemination Days 40, 90, 120, 150, 180, 210, and at parturition or until the time of abortion detection. Blood plasma was tested for antibodies against N. caninum using ELISA. The non-aborting cows were divided into two groups according to whether their antibody values in the second half of gestation had increased or not, while aborting cows were classified as those showing an antibody peak before abortion or those not showing a pre-abortion peak. Differences in antibody values throughout pregnancy in each group of non-aborting and aborting cows were analysed by GLM repeated measures of analysis of variance. While 32 non-aborting cows (49%) showed a significant and consistent increase in anti-Neospora antibody values during the second half of gestation, antibody values in the remaining 33 non-aborting cows were practically constant throughout gestation. An antibody peak around abortion was observed in 11 aborting cows (52%), while antibody values in the remaining 10 aborting cows were similar before and at abortion. Seroprevalence fluctuations, defined as seronegative blood samples at some point during the gestation period, were, furthermore, observed in 2 aborting and 11 non-aborting cows. Our results indicate two clearly distinguishable types of humoral immune dynamics throughout gestation: an increased or flat production of antibodies during the second half of gestation in non-aborting animals and before abortion in aborting cows. The observation that some Neospora-infected dams can exhibit negative antibody values at any time during gestation, particularly at parturition or abortion, prompts future studies designed to explore the use of new ELISA strategies at the farm level.
- ItemOpen AccessReal-time tree-foliage surface estimation using a ground laser scanner(Institute of Electrical and Electronics Engineers (IEEE), 2007) Palacín Roca, Jordi; Pallejà Cabrè, Tomàs; Tresánchez Ribes, Marcel; Ribes Dasi, Manuel; Llorens Calveras, Jordi; Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon; Sanz Cortiella, Ricardo; Masip Vilalta, Joan; Arnó Satorra, JaumeThe optimization of most pesticide and fertilizer applications is based on overall grove conditions. In this work we measurements. Recently, Wei [9, 10] used a terrestrial propose a measurement system based on a ground laser scanner to LIDAR to measure tree height, width and volume developing estimate the volume of the trees and then extrapolate their foliage a set of experiments to evaluate the repeatability and surface in real-time. Tests with pear trees demonstrated that the accuracy of the measurements, obtaining a coefficient of relation between the volume and the foliage can be interpreted as variation of 5.4% and a relative error of 4.4% in the linear with a coefficient of correlation (R) of 0.81 and the foliar estimation of the volume but without real-time capabilities. surface can be estimated with an average error less than 5 %.
- ItemOpen AccessGlycerol as a starting material to prepare palmitate derivatives(Asociación de Químicos e Ingenieros del Instituto Químico de Sarriá, 2007) Eras i Joli, Jordi; Balcells Fluvià, Mercè; Canela i Garayoa, RamonGlycidyl palmitate, used to obtain high purity monoglycerides and epoxy resins, can be obtained from glycerol using a two-step process. The first step of this new approach consists in a reaction of esterification-chlorination of glycerol. An elimination reaction using Cs2CO3 allows the corresponding glycidyl ester to be prepared from the chlorohydrin ester intermediate.
- ItemRestrictedEdible coatings with antibrowning agents to maintain sensory quality and antioxidant properties of fresh-cut pears(Elsevier, 2008) Oms Oliu, Gemma; Soliva-Fortuny, Robert; Martín Belloso, OlgaThe effect of alginate-based (2%, w/v), pectin-based (2%, w/v) and gellan-based (0.5%, w/v) edible coatings containing N-acetylcysteine at 0.75% (w/v) and glutathione at 0.75% (w/v) on gas exchange, antioxidant properties, sensory quality and microbial stability of fresh-cut ‘Flor de Invierno’ pears, was investigated for 14 d at 4 ◦C. The use of polysaccharide-based edible coatings increased the water vapor resistance and reduced ethylene production of coated fresh-cut pears. The incorporation of N-acetylcysteine and glutathione into coating formulations not only reduced microbial growth compared with samples not containing antioxidants but also was effective in preventing fresh-cut pears from browning for 2 weeks without affecting firmness of fruit wedges. The increased vitamin C and total phenolic content observed in pear wedges coated with alginate, gellan and pectin including antioxidants contributed to maintain their antioxidant potential. In addition, coatings with alginate or pectin best maintained sensory attributes of pear wedges for 14 d.
- ItemOpen Access[BMIM][PF6] Promotes the synthesis of halohydrin esters from diols using potassium halides(Japan Society for Analytical Chemistry, 2008) Oromí Farrús, Mireia; Eras i Joli, Jordi; Villorbina Noguera, Gemma; Torres i Grifo, Mercè; Llopis-Mestre, Verónica; Welton, Tom; Canela i Garayoa, RamonHaloesterification of diverse diols with various carboxylic acids was achieved using potassium halides (KX) as the only halide source in ionic liquids. The best yield was obtained in [BMIM][PF6] when 1,2-octanediol, palmitic acid and KBr were used. This yield was 85% and the regioisomer with the bromine in primary position was present in a 75:25 ratio. The regioisomeric ratio could be improved using either KCl or some phenylcarboxylic acids. [BMIM][PF6] acts as both reaction media and catalyst of the reaction. To the best of our knowledge, this type of combined reaction using an ionic liquid is unprecedented. The other solvents tested did not lead either to the same yield or to the same regioisomeric ratio.
- ItemRestrictedCombining AlCl3·6H2O and an ionic liquid to prepare chlorohydrin esters from glycerol(Elsevier, 2009) Villorbina Noguera, Gemma; Tomàs, Albert; Escribà i Gelonch, Marc; Oromí Farrús, Mireia; Eras i Joli, Jordi; Balcells Fluvià, Mercè; Canela i Garayoa, RamonWe describe here the first example in which glycerol has been transformed into chlorohydrin esters using an ionic liquid and hydrated aluminium chloride. The method avoids using Crown-18 ether, which was needed to obtain a similar yield when KCl was used. Alkyl and aryl acids can be used, although yields are very dependent on the carboxylic acid used.
- ItemRestrictedSpecific anti-Neospora caninum IgG1 and IgG2 antibody responses during gestation in naturally infected cattle and their relationship with gamma interferon production(Elsevier, 2009) Almería, S.; Nogareda, Carmina; Santolaria Blasco, Pilar; García Ispierto, Irina; Yániz Pérez de Albéniz, Jesús; López Gatius, FernandoGamma interferon (IFN-g) production has been attributed a protective role against abortion in Neospora-infected dairy cows. This study investigate possible relationships between plasma levels of the N. caninum-specific immunoglobulin (Ig) isotypes IgG1 and IgG2 and IFN-g production throughout gestation in dairy cows naturally infected with the parasite. Data were obtained from 31 pregnant Neospora-seropositive animals. Blood samples were collected on gestation days 40, 90, 120, 150, 180 and 210 or until abortion. Ten pregnancies ended in abortion. One of the 11 cows producing IFN-g suffered abortion (9.1% of the cows producing IFN-g). Non-aborting cows producing IFN-g (n = 10) showed a significantly higher IgG2/IgG1 antibody ratio throughout the gestation period than cows not producing IFN-g (n = 11). A significant negative effect of IFN-g production on IgG1 antibodies was also observed, while IFN-g production did not affect IgG2 antibody levels. In contrast, higher levels of IgG2 antibodies compared to IgG1 antibodies were observed over the whole of gestation in aborting animals, both in those not producing IFN-g and in the single aborting cow that produced the cytokine. Our findings indicate that a Th1 immune response, in which IgG2 antibodies prevail, could be protective against N. caninum abortion, but only in the presence of IFN-g production. On their own, elevated IgG2 antibody titres appear to be insufficient to protect dams chronically infected with N. caninum against abortion.
- ItemOpen AccessObtaining the three-dimensional structure of tree orchards from remote 2D terrestrial LIDAR scanning(Elsevier, 2009) Rosell Polo, Joan Ramon; Llorens Calveras, Jordi; Sanz Cortiella, Ricardo; Arnó Satorra, Jaume; Ribes Dasi, Manuel; Masip Vilalta, Joan; Escolà i Agustí, Alexandre; Camp, Ferran; Solanelles Batlle, Francesc; Gràcia, Felip; Gil Moya, Emilio; Val, Luis; Planas de Martí, Santiago; Palacín Roca, JordiIn recent years, LIDAR (light detection and ranging) sensors have been widely used to measure environmental parameters such as the structural characteristics of trees, crops and forests. Knowledge of the structural characteristics of plants has a high scientific value due to their influence in many biophysical processes including, photosynthesis, growth, CO2-sequestration and evapotranspiration, playing a key role in the exchange of matter and energy between plants and the atmosphere, and affecting terrestrial, above-ground, carbon storage. In this work, we report the use of a 2D LIDAR scanner in agriculture to obtain three-dimensional (3D) structural characteristics of plants. LIDAR allows fast, non-destructive measurement of the 3D structure of vegetation (geometry, size, height, cross-section, etc.). LIDAR provides a 3D cloud of points, which is easily visualized with Computer Aided Design software. Three-dimensional, high density data are uniquely valuable for the qualitative and quantitative study of the geometric parameters of plants. Results are demonstrated in fruit and citrus orchards and vineyards, leading to the conclusion that the LIDAR system is able to measure the geometric characteristics of plants with sufficient precision for most agriculture applications. The developed system made it possible to obtain 3D digitalized images of crops, from which a large amount of plant information – such as height, width, volume, leaf area index and leaf area density – could be obtained. There was a great degree of concordance between the physical dimensions, shape and global appearance of the 3D digital plant structure and the real plants, revealing the coherence of the 3D tree model obtained from the developed system with respect to the real structure. For some selected trees, the correlation coefficient obtained between manually measured volumes and those obtained from the 3D LIDAR models was as high as 0.976.
- ItemOpen AccessA tractor-mounted scanning LIDAR for the non-destructive measurement of vegetative volume and surface area of tree-row plantations: a comparison with conventional destructive measurements(Elsevier, 2009) Rosell Polo, Joan Ramon; Sanz Cortiella, Ricardo; Llorens Calveras, Jordi; Arnó Satorra, Jaume; Escolà i Agustí, Alexandre; Ribes Dasi, Manuel; Masip Vilalta, Joan; Camp, Ferran; Gràcia, Felip; Solanelles Batlle, Francesc; Pallejà Cabrè, Tomàs; Val, Luis; Planas de Martí, Santiago; Gil Moya, Emilio; Palacín Roca, JordiThe use of a low-cost tractor-mounted scanning Light Detection and Ranging (LIDAR) system for capable of making non-destructive recordings of tree-row structure in orchards and vineyards is described. Field tests consisted of several LIDAR measurements on both sides of the crop row, before and after defoliation of selected trees. Summary parameters describing the tree-row volume and the total crop surface area viewed by the LIDAR (expressed as a ratio with ground surface area) were derived using a suitable numerical algorithm. The results for apple and pear orchards and a wine producing vineyard were shown to be in reasonable agreement with the results derived from a destructive leaf sampling method. Also, good correlation was found between manual and sensor-based measurements of the vegetative volume of tree-row plantations. The Tree Area Index parameter, TAI, gave the best correlation between destructive and non-destructive (i.e. LIDAR-based) determinants of crop leaf area. The LIDAR system proved to be a powerful technique for low cost, prompt and non-destructive estimates of the volume and leaf-area characteristics of plants.
- ItemRestrictedA tandem Finkelstein-rearrangement–elimination reaction: a straightforward synthetic route to allyl esters(Elsevier, 2009) Eras i Joli, Jordi; Escribà i Gelonch, Marc; Villorbina Noguera, Gemma; Oromí Farrús, Mireia; Balcells Fluvià, Mercè; Canela i Garayoa, RamonAllyl esters can be obtained by a Finkelstein-rearrangement–elimination reaction of 2-chloro-1-(chloromethyl)ethyl esters induced by NaI. Sodium iodide can be used below equivalence using a reductive agent as sodium thiosulfate. High yields are obtained with most of the diverse esters studied. The method described avoids the use of allyl alcohol as a reagent. 2-Chloro-1-(chloromethyl)ethyl esters are prepared from glycerol, the main by-product of biodiesel industry. The effectiveness of iodine as reagent to hydrolyze allyl esters is also confirmed.
- ItemOpen AccessThree-dimensional antennal lobe atlas of the oriental fruitmoth, Cydia molesta (Busck) (Lepidoptera: Tortricidae): comparison of male and female glomerular organization(Springer-Verlag, 2009) Varela, Nelia; Couton, Louise; Gemeno Marín, César; Avilla Hernández, Jesús; Rospars, Jean-Pierre; Anton, SylviaThe oriental fruit moth Cydia molesta is an important pest and the behavioural role of olfactory signals such as pheromones and plant volatiles have been studied extensively in both sexes. To understand odour processing further, however, detailed knowledge of the anatomy of the olfactory system is crucial. In the present study, an atlas of the antennal lobe (AL) is presented based on the three-dimensional reconstructions of both ALs of three male and three female brains by means of neuroanatomical and computational approaches. We identified 48-49 'ordinary' glomeruli and one large glomerulus situated at the entrance of the antennal nerve in males, and 49-52 'ordinary' glomeruli and one large glomerulus in the ventro-medial part of the AL in females. Anomalous supernumerary, anomalous missing and sexually dimorphic glomeruli were found in the studied individuals in greater numbers than in other lepidopteran species. Male and female maps were compared with respect to glomerular size and position with 45 glomeruli being matched, indicating a conserved glomerular pattern between the sexes. Three additional glomeruli were sexually dimorphic in size and five male-specific and six female-specific glomeruli were also found. Palp backfills resulted in the staining of a unique glomerulus in both sexes identified as the sexually dimorphic glomerulus 45. This glomerulus was never stained from antennal backfills, which stained the other glomeruli of the AL. The three-dimensional atlas can now be used to elucidate the functional role of individual glomeruli in both sexes of C. molesta.
- ItemOpen AccessDesign of a decision support method to determine volume rate for vineyard spraying(American Society of Agricultural and Biological Engineers, 2009) Gil Moya, Emilio; Escolà i Agustí, AlexandreDose determination in crops such as grapevine, which develops a large canopy within a relatively short period of time, becomes a key factor on the final success of plant protection product (PPP) application. Efficacy of PPP applications depends on many factors. Based on multiple data obtained over several years in real working conditions using different types of sprayers in vineyards, and by adding a complete data base about crop characteristics (structure, crop stage, leaf area, LAI, etc.), the objective of this work has been to develop an easy and useful tool, DOSAVIÑA, able to determine the optimal volume rate in spray applications in vineyards. DOSAVIÑA, based on a spreadsheet (Microsoft Excel ), allows quantifying all the parameters involved in the application process (sprayer type, crop characteristics, working conditions, weather, etc.), and to determine the efficiency of the application. By selecting and choosing the different options for each parameter (crop, pesticide, working conditions, weather conditions, sprayer, and droplet characteristics) the program calculates the theoretical volume rate (L ha‐1) based on two different methods, the Optimal Coverage Method and the Tree‐Row‐Volume method. Results obtained with DOSAVIÑA allow reducing the recommended volume rate in comparison with traditional application rate selection managed for farmers. In order to make a complete and useful tool, the program includes the possibility to calculate the final working parameters (pressure, nozzle type, and size) according to the recommendations on volume rate (L ha‐1) obtained.
- ItemOpen AccessReview. Precision viticulture. Research topics, challenges and opportunities in site-specific vineyard management(Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (Espanya), 2009) Arnó Satorra, Jaume; Martínez Casasnovas, José Antonio; Ribes Dasi, Manuel; Rosell Polo, Joan RamonPrecision Viticulture (PV) is a concept that is beginning to have an impact on the wine-growing sector. Its practical implementation is dependant on various technological developments: crop sensors and yield monitors, local and remote sensors, Global Positioning Systems (GPS), VRA (Variable-Rate Application) equipment and machinery, Geographic Information Systems (GIS) and systems for data analysis and interpretation. This paper reviews a number of research lines related to PV. These areas of research have focused on four very specific fields: 1) quantification and evaluation of within-field variability, 2) delineation of zones of differential treatment at parcel level, based on the analysis and interpretation of this variability, 3) development of Variable-Rate Technologies (VRT) and, finally, 4) evaluation of the opportunities for site-specific vineyard management. Research in these fields should allow winegrowers and enologists to know and understand why yield variability exists within the same parcel, what the causes of this variability are, how the yield and its quality are interrelated and, if spatial variability exists, whether site-specific vineyard management is justifiable on a technical and economic basis.