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Effects of leaning grapevine canopy to the West on water use efficiency and yield under Mediterranean conditions
Get PDFThis study tested the possibility of improving whole-canopy water use efficiency (WUE) of grapevines (cv. Bobal) by maximizing radiation interception during the mornings and limiting this during the afternoons, when the vapour pressure deficit and the evaporative demand are higher. The three-year study consisted of two trials conducted in parallel on North-South row oriented potted- and field-grown grapevines. In both trials, performance in terms of vine water use, yield and WUE in a vertical shoot positioned (VSP) system was compared with that of vines leaned 30° towards West (WSP). Potted vines were fully irrigated, whereas field-grown vines were submitted to rain-fed and deficit irrigation conditions. In potted plants, there was no difference in daily transpiration between vines from the WSP and VSP treatments, but transpiration in the mornings was higher in WSP vines. Dry matter and berry size increased in WSP compared to VSP vines. In the field, watering regime had a greater effect than canopy inclination on vine performance. Nonetheless, the WSP system increased leaf area by 13%, yield by 12% and WUE by 11% compared to VSP, although differences in WUE were not statistically significant and the effect on yield was negligible under rain-fed conditions. In both trials, the WSP system did not have a major effect on grape composition (soluble solids, pH, total acidity, concentrations of anthocyanins and polyphenols). In conclusion, this pioneering three-year study proved that leaning vine canopies to the West increased grapevine performance despite the great effect that environmental conditions exerted each year on the data obtained. Further research is required to study the effects of different patterns of light interception on carbon balance and grape biochemical composition
Contribución de la raíz a la sostenibilidad y resiliencia de los cultivos de tomate y cítricos
No full textEl sistema agrario está basado en un conjunto de variedades generalmente seleccionadas bajo condiciones óptimas de cultivo por lo que su acervo genético representa una muestra muy reducida de los genes existentes en los recursos fitogenéticos de las especies cultivadas. La raíz tiene un papel fundamental en la adquisición de agua y nutrientes y en la interacción de la planta con los microorganismos del suelo por lo que el uso de patrones puede ser una buena estrategia para aumentar la sostenibilidad y resiliencia de los cultivos de cítricos y tomate utilizando nuevo germoplasma. A pesar de que el uso del injerto está muy extendido desde hace mucho tiempo, se desconoce el porqué de la mayoría de sus acciones beneficiosas. En el seminario se expondrán los sistemas biológicos y herramientas (análisis de QTL) que utilizamos para explorar los recursos fitogenéticos y descubrir que pueden ser beneficiosos en la mejora de patrones de estas especie
Guidelines for statistically sound and risk-based surveys of Phyllosticta citricarpa
Get PDFAt the request of the European Commission, EFSA prepared these specific guidelines to guide the surveyor through the design of statistically sound and risk-based surveys for Phyllosticta citricarpa, integrating the key biological information. Based on examples, three different survey designs are simulated:(i) detection surveys to substantiate pest freedom, (ii) delimiting surveys to determine the boundaries of an infested zone, and (iii) buffer zone surveys to monitor a zone ensuring pest detection at low levels of prevalence.The first step of the survey design consists of setting the goals of the survey, characterising the host plant population and the methods used to identify the pest. All survey parameters are quantified taking into accountthe importance of the related assumptions. The more accurateand robust the information used for selecting and estimating the survey parameters, the more robust the conclusions of the survey will be. The second step of the survey design consists of the sample size (i.e. number of trees)calculation using the survey parameters as inputs of the proposed statistical tool (EFSA RiBESS+).The last step of the survey design is the allocation of the samples in the survey area which depends on the information available on the target population and risk factors. The robustness of the conclusions of surveys designed using the proposed approaches strongly depends on the survey preparation. The methodology proposed allows surveys to be compared across time and space, thus contributing to the harmonisation of the P.citricarpasurveys across the EU. The extremely flexible approach allows the surveys to be tailored to each specific situation in the Member States, taking into account the citrus tree distribution and available resources. The success of a good survey design relies on the technical aspects of the survey preparation and on the involvement of the risk managers
RobHortic: A Field Robot to Detect Pests and Diseases in Horticultural Crops by Proximal Sensing
Get PDFRobHortic is a remote‐controlled field robot that has been developed for inspecting the
presence of pests and diseases in horticultural crops using proximal sensing. The robot is equipped
with colour, multispectral, and hyperspectral (400–1000 nm) cameras, located looking at the ground
(towards the plants). To prevent the negative influence of direct sunlight, the scene was illuminated
by four halogen lamps and protected from natural light using a tarp. A GNSS (Global Navigation
Satellite System) was used to geolocate the images of the field. All sensors were connected to an onboard
industrial computer. The software developed specifically for this application captured the
signal from an encoder, which was connected to the motor, to synchronise the acquisition of the
images with the advance of the robot. Upon receiving the signal, the cameras are triggered, and the
captured images are stored along with the GNSS data. The robot has been developed and tested
over three campaigns in carrot fields for the detection of plants infected with ‘Candidatus
Liberibacter solanacearum’. The first two years were spent creating and tuning the robot and
sensors, and data capture and geolocation were tested. In the third year, tests were carried out to
detect asymptomatic infected plants. As a reference, plants were analysed by molecular analysis
using a specific real‐time Polymerase Chain Reaction (PCR), to determine the presence of the target
bacterium and compare the results with the data obtained by the robot. Both laboratory and field
tests were done. The highest match was obtained using Partial Least Squares‐Discriminant Analysis
PLS‐DA, with a 66.4% detection rate for images obtained in the laboratory and 59.8% for images
obtained in the field
El control de las enfermedades de poscosecha y las alternativas a los fungicidas químicos convencionales
Get PDFLas pérdidas económicas ocasionadas por las patologías de poscosecha constituyen uno de los principales problemas del sector de los cítricos en España. La gran mayoría de las enfermedades que se producen desde que los frutos son recolectados hasta que llegan al consumidor son debidas a hongos patógenos causantes de podredumbres. Las pérdidas provocadas por las enfermedades son muy variables y dependen del área productora, la especie y el cultivar, la edad y el estado de los árboles, las condiciones climatológicas durante toda la campaña, la época y la forma de recolección, el manejo de los frutos en poscosecha, las condiciones de almacenamiento y el mercado de destino. En general, las enfermedades de poscosecha de los cítricos se clasifican en dos grupos diferentes según el momento predominante de la infección: a) enfermedades causadas por infecciones que tienen lugar antes de la cosecha y permanecen latentes o inactivas hasta después de la recolección
y b) enfermedades causadas por infecciones que tienen lugar durante o después de la cosecha. Los
hongos causantes de las primeras se denominan genéricamente patógenos latentes o quiescentes y
los que originan las segundas son los llamados patógenos de herida
Structure and Expression of Bud Dormancy-Associated MADS-Box Genes (DAM) in European Plum
Get PDFBud dormancy in temperate perennials ensures the survival of growing meristems under the harsh environmental conditions of autumn and winter, and facilitates an optimal growth and development resumption in the spring. Although the molecular pathways controlling the dormancy process are still unclear, DORMANCY-ASSOCIATED MADS-BOX genes (DAM) have emerged as key regulators of the dormancy cycle in different species. In the present study, we have characterized the orthologs of DAM genes in European plum (Prunus domestica L.). Their expression patterns together with sequence similarities are consistent with a role of PdoDAMs in dormancy maintenance mechanisms in European plum. Furthermore, other genes related to dormancy, flowering, and stress response have been identified in order to obtain a molecular framework of these three different processes taking place within the dormant flower bud in this species. This research provides a set of candidate genes to be genetically modified in future research, in order to better understand dormancy regulation in perennial species
Effect of different housing systems (single and group penning) on the health and welfare of commercial female rabbits
Get PDFIn recent decades, concern about rabbit welfare and sustainability has increased. The housing system is a very important factor for animal welfare. However, information about how different available housing types for female rabbits affect their health status is scarce, but this is an important factor for their welfare. Hence, the objective of this study was to evaluate the health status of female rabbits in five common housing systems: three different single-housing systems with distinct available surfaces and heights; a single-housing system with a platform; a collective system. Female rabbits in the collective and platform cages had greater cortisol concentrations in hair than those in the single-housing system with no platform. Haptoglobin concentrations and kit mortality rates during lactation were greater for the collective-cage female rabbits. The collective group had more culled females and more lesions than in the other groups. The main reasons for culling in all the groups were reproduction problems and presence of abscesses, and the collective group of females was the most affected. In conclusion, it appears that keeping females together in collective systems negatively affects their health status and welfare, while single-housing systems imply lower kit mortality rates during lactation and cortisol concentrations, and fewer lesions in female rabbits
Synthetic Polyploidy in Grafted Crops
Get PDFSynthetic polyploids have been extensively studied for breeding in the last decade. However, the use of such genotypes at the agronomical level is still limited. Polyploidization is known to modify certain plant phenotypes, while leaving most of the fundamental characteristics apparently untouched. For this reason, polyploid breeding can be very useful for improving specific traits of crop varieties, such as quality, yield, or environmental adaptation. Nevertheless, the mechanisms that underlie polyploidy-induced novelty remain poorly understood. Ploidy-induced phenotypes might also include some undesired effects that need to be considered. In the case of grafted or composite crops, benefits can be provided both by the rootstock’s adaptation to the soil conditions and by the scion’s excellent yield and quality. Thus, grafted crops provide an extraordinary opportunity to exploit artificial polyploidy, as the effects can be independently applied and explored at the root and/or scion level, increasing the chances of finding successful combinations. The use of synthetic tetraploid (4x) rootstocks may enhance adaptation to biotic and abiotic stresses in perennial crops such as apple or citrus. However, their use in commercial production is still very limited. Here, we will review the current and prospective use of artificial polyploidy for rootstock and scion improvement and the implications of their combination. The aim is to provide insight into the methods used to generate and select artificial polyploids and their limitations, the effects of polyploidy on crop phenotype (anatomy, function, quality, yield, and adaptation to stresses) and their potential agronomic relevance as scions or rootstocks in the context of climate change
Uso eficiente del agua en los frutales del Sureste español
Get PDFEl agua es un patrimonio que hay que proteger, defender y tratar acorde al recurso
escaso que es, y así lo indica la DMA (Directiva Marco del Agua, 2000/60/CE). En la
Vega Baja del Segura (Alicante, Sureste español) la gestión de los recursos hídricos en
las explotaciones agrarias está muy condicionada por su escasez, y el agua es un bien con
un aprovechamiento muy intensivo. La agricultura se caracteriza por su larga tradición en
la zona, con producciones de excelente calidad y buena competitividad, para lo que es
fundamental el buen clima, la calidad de las tierras y la experiencia de los agricultores.
Sin embargo el sector agrario está perdiendo importancia, en parte por las limitaciones
hidrológicas.
La escasez de agua hace que este recurso tenga un alto coste de oportunidad y
exige un uso muy eficiente. En la DMA Europea se plantean distintas medidas para
promover el uso eficiente y sostenible del agua en los territorios. Precisamente el
conocimiento de los niveles de eficiencia que tienen las producciones agrarias en el uso
del agua de riego es previo a cualquier posterior iniciativa, ya sea pública o privada.
En este trabajo se analiza la eficiencia de los principales frutales de regadío de la
zona. Para ello, se han realizado cálculos de distintos indicadores de eficiencia, a partir
de datos tomados a agricultores de tres de las principales UDAs (unidades de demanda
agraria) que recoge el actual PHDS (Plan Hidrológico de la Demarcación del Segura).
Estas UDAs cubren una superficie bruta de 41.700 ha, y tienen sistemas de riegos
distintos en función del grado de modernización de las explotaciones. Tras el análisis
queda patente que los cultivos con una mayor tradición en la zona (como son limón o
granado) son también los que utilizan el agua con más eficiencia