An index from sap flow records to schedule irrigation in super-high density olive orchards

8 pages, 5 figures, 11 references.-- IX International Workshop on Sap Flow, celebrado del 4-7 de junio 2013, en Gante, Bélgica.Regulated deficit irrigation (RDI), recommended for super-high density (SHD) olive orchards, requires a precise control of irrigation. Water must be supplied on the phenological stages when the plant is most sensitive to water stress, but irrigation promotes plant vigour, and excessive growth hampers management in SHD orchards. A reliable water stress indicator is needed, therefore, for the proper management of RDI. Here we present an evaluation of the performance of DEp, an index previously reported by Cuevas et al. (2012). The index is derived from sap flow measurements in RDI trees and in fully irrigated trees used as a reference. We evaluated the index during the irrigation seasons of 2011 and 2012, in an 'Arbequina' olive orchard with 1667 trees ha-1 close to Seville, southwest Spain. The index showed a potential for scheduling RDI strategies, although its reliability decreased on periods of fluctuating atmospheric demand. The required data analyses and data interpretation make the DEp index suitable for well-trained users only.This work was funded by the Spanish Ministry of Science and innovation (research project AGL2009-11310/AGR), by the Junta de Andalucía (research project AGR-6456-2010) and by the FEDER programme.Peer Reviewe

Sap flow response to olive water stress: a comparative study with trunk diameter variations and leaf turgor pressure

11 pages, 3 figures, 19 references.-- VIII International Symposium on Sap Flow, celebrado del 8-12 de mayo 2011, en Volterra, Italia.The aim of this work was to evaluate the potential of used sap flow (SF), trunk diameter variation (TDV) and leaf turgor (LT) sensors for assessing water stress in a `Arbequina¿ hedgerow olive orchard with 1667 trees ha-1. Measurements were made in control trees irrigated to replace 100% of the crop water needs, and in trees under two regulated deficit irrigation strategies, 60RDI and 30RDI, in which irrigation replaced ca. 60% and 30% of the control, respectively. From the SF and TDV measurements we calculated the daily difference, both for tree water consumption (DEp) and maximum trunk diameter (DMXTD), between RDI trees and control trees. With the LT sensors we recorded the leaf patch output pressure (Pp), which is related to the leaf turgor pressure. Both DEp and DMXTD responded quickly and markedly to changes in water stress. The seasonal dynamics of both indices agreed with that of the stem water potential. A decrease in the reliability of DEp was recorded on days of highly variable atmospheric demand. The LT sensors also showed to be highly sensitive to changes on water stress. Any of the three methods have a potential as indicators for precise irrigation in hedgerow olive orchards with high plant density and low soil water-holding capacity.This experiment was funded by the Spanish Ministry of Science and Innovation, research project AGL2009-11310/AGR.Peer Reviewe

The Granulocyte colony-stimulating factor produces long-term changes on gene and miRNA expression profiles in CD34+ cells from healthy donors

Granulocyte colony-stimulating factor is the most commonly used cytokine for the mobilization of hematopoietic progenitor cells from healthy donors for allogeneic stem cell transplantation. Although the administration of this cytokine is considered safe, knowledge about its long-term effects, especially in hematopoietic progenitor cells, is limited. On this background, the aim of our study was to analyze whether or not granulocyte colony-stimulating factor induces changes in gene and microRNA expression profiles in hematopoietic progenitor cells from healthy donors, and to determine whether or not these changes persist in the long-term. For this purpose, we analyzed the whole genome expression profile and the expression of 384 microRNA in CD34(+) cells isolated from peripheral blood of six healthy donors, before mobilization and at 5, 30 and 365 days after mobilization with granulocyte colony-stimulating factor. Six microRNA were differentially expressed at all time points analyzed after mobilization treatment as compared to the expression in samples obtained before exposure to the drug. In addition, 2424 genes were also differentially expressed for at least 1 year after mobilization. Of interest, 109 of these genes are targets of the differentially expressed microRNA also identified in this study. These data strongly suggest that granulocyte colony-stimulating factor modifies gene and microRNA expression profiles in hematopoietic progenitor cells from healthy donors. Remarkably, some changes are present from early time-points and persist for at least 1 year after exposure to the drug. This effect on hematopoietic progenitor cells has not been previously reported

Heat-pulse measurements of sap flow in olives for automating irrigation: tests, root flow and diagnostics of water stress

26 páginas, 10 figuras, 1 tabla, 32 referencias.-- [email protected] compensation heat-pulse method for measuring sap flow is tested here in olive trees (Olea europaea L.). We describe a rigorous three-way examination of the robustness of the technique for this species, and examine the potential of the technique for an automatic control of the irrigation system. Two tests were carried out using heat-pulse gear inserted into the stem of 12-year-old ‘Manzanilla’ olive trees. One test used forced-flow through a stem section, and the other involved measured water uptake by an excised tree. The measured sap flow in these two tests was in agreement with calculations from heat-pulse velocities when using a standard ‘wound correction’ to account for the presence of the probes and the disruption to the sap flow. Thus, this technique for monitoring transpiration can, we feel, be used with confidence in olives. The third experiment was carried out in the field, where we analysed sap flow data from two 29- year-old olive trees—one tree was under regular drip irrigation and the other was from dry-farming conditions. We use measurements of sap flow in the trunk to examine the hydraulic functioning of the tree, and to explore some diagnostics of water stress. Our heat-pulse measurements in the irrigated olive tree exhibited a profile of sap flow that was weighted towards the outer xylem of the tree trunk while the water-stressed trees in the field showed a profile of sap flow weighted towards the centre of the trunk. The loss of hydraulic functioning in the outermost section of the vascular system, as a result of water stress, we consider to be due both to stomatal control and to embolisms in the xylem vessels. The fourth experiment was also carried out in the field, in which sap flow measurements were made at three locations in the trunk as well as in two roots of another 29-year-old olive tree. The soil explored by each root, on opposite sides of the trunk, was differentially wetted by separate irrigation of each side. Our data showed that the surface roots were able to absorb water immediately after wetting, despite a reasonably prolonged period of moderate drought. Root activity quickly shifted to the regions where the soil had been wetted. A root in dry soil exhibited no flow at night, whereas sap flows of about 0.02 l h 1 were measured around midnight in the root drawing water from the wetter soil. Our observations suggest that the hydraulic behaviour of the trunk and surface roots might be used as a diagnostic of the onset, or severity, of water stress. Here there is not the imperative to replicate, for the prime goal is not transpiration estimation. Rather interpretation of the diurnal dynamics is used to infer the onset, or severity of water stress. The compensation heat-pulse seems a suitable technique for automatically controlling the irrigation system of olives, and probably other trees, based either on the estimation of the short-time dynamics of transpiration, or on changes in the hydraulic behaviour of the trees.The Comisión Interministerial de Ciencia y Tecnología of the Spanish Ministry of Education and Science financial support this project.Peer reviewe

Heat-pulse measurements of sap flow in olives for automating irrigation: tests, root flow and diagnostics of water stress

26 páginas, 10 figuras, 1 tabla, 32 referencias.-- [email protected] compensation heat-pulse method for measuring sap flow is tested here in olive trees (Olea europaea L.). We describe a rigorous three-way examination of the robustness of the technique for this species, and examine the potential of the technique for an automatic control of the irrigation system. Two tests were carried out using heat-pulse gear inserted into the stem of 12-year-old ‘Manzanilla’ olive trees. One test used forced-flow through a stem section, and the other involved measured water uptake by an excised tree. The measured sap flow in these two tests was in agreement with calculations from heat-pulse velocities when using a standard ‘wound correction’ to account for the presence of the probes and the disruption to the sap flow. Thus, this technique for monitoring transpiration can, we feel, be used with confidence in olives. The third experiment was carried out in the field, where we analysed sap flow data from two 29- year-old olive trees—one tree was under regular drip irrigation and the other was from dry-farming conditions. We use measurements of sap flow in the trunk to examine the hydraulic functioning of the tree, and to explore some diagnostics of water stress. Our heat-pulse measurements in the irrigated olive tree exhibited a profile of sap flow that was weighted towards the outer xylem of the tree trunk while the water-stressed trees in the field showed a profile of sap flow weighted towards the centre of the trunk. The loss of hydraulic functioning in the outermost section of the vascular system, as a result of water stress, we consider to be due both to stomatal control and to embolisms in the xylem vessels. The fourth experiment was also carried out in the field, in which sap flow measurements were made at three locations in the trunk as well as in two roots of another 29-year-old olive tree. The soil explored by each root, on opposite sides of the trunk, was differentially wetted by separate irrigation of each side. Our data showed that the surface roots were able to absorb water immediately after wetting, despite a reasonably prolonged period of moderate drought. Root activity quickly shifted to the regions where the soil had been wetted. A root in dry soil exhibited no flow at night, whereas sap flows of about 0.02 l h 1 were measured around midnight in the root drawing water from the wetter soil. Our observations suggest that the hydraulic behaviour of the trunk and surface roots might be used as a diagnostic of the onset, or severity, of water stress. Here there is not the imperative to replicate, for the prime goal is not transpiration estimation. Rather interpretation of the diurnal dynamics is used to infer the onset, or severity of water stress. The compensation heat-pulse seems a suitable technique for automatically controlling the irrigation system of olives, and probably other trees, based either on the estimation of the short-time dynamics of transpiration, or on changes in the hydraulic behaviour of the trees.The Comisión Interministerial de Ciencia y Tecnología of the Spanish Ministry of Education and Science financial support this project.Peer reviewe

Influence of the soil water content and distribution on both the hydraulic and transpiration performance of 'Manzanilla' olive trees

8 páginas, 4 figuras, 20 referencias.-- VI International Symposium on Irrigation of Horticultural Crops, celebrado del 2-6 de noviembre de 2006 en Viña del Mar, Chile.-- [email protected] work was made with mature 'Manzanilla' olive trees in an orchard of a semi-arid area in southern Spain. Three water treatments were considered: Rainfed, in which the trees had rainfall as the only source of water supply; FAO, in which the trees were under localized irrigation to replace the crop water demand, with some roots left in drying soil; Pond, in which the whole rootzones of the trees were maintained under non-limiting soil water conditions for the whole dry season. Our aim was to obtain information on the mechanisms behind the reduction of transpiration (Ep) in the FAO trees, as compared to the Pond trees. Our results show a near-isohydric behaviour of the FAO trees, i.e. those trees under localized irrigation in which some roots are left in drying showed lower stomatal conductance than the Pond trees in which all roots were in wetted soil. This helped the FAO trees to maintain similar leaf water potentials than the Pond trees. In addition, the FAO trees maintained a constant difference between the water potential of the canopy and that in the soil. This has been described as an isohydrodynamic behaviour, and it is thought to be an improvement over a typically anisohydric behaviour. These mechanisms were behind the similar values of tree hydraulic conductance (K p) found in the FAO and Pond treatments. The Rainfed trees showed lower Kp values because of the low Ep values of those trees, due to the low soil water availability in that treatment. Our results show, however, that the Rainfed trees were able to maintain similar values of Kp all throughout the dry season, which shows that the hydraulic efficiency of the xylem of those trees was little affected by embolism, despite of the high demanding conditions in the area.This work has been funded by the Spanish Ministry of Education and Science, research project No.AGL2006-04666/AGR, and by the EU, research project ref. STREP 023120.Peer Reviewe

Regulated deficit irrigation in table olive trees during a sensitive period

Olive tree is one of the most important irrigated fruit at Spain (around 400.000 ha). The water needs in olive orchard are greater than the water availability. Therefore, deficit conditions are common at the field. The aim of this work is to study a regulated deficit irrigation (RDI) scheduling based on midday stem water potential (Y) that limits irrigation before harvest. The experiment was performed at La Hampa experimental farm (Coria del río, Seville, Spain) in 45 years-old olive (cv Manzanillo). Three irrigation treatments in a complete randomized block design were performed during 2014.This research was supported by the Spanish Ministerio de Economía y Competitividad (MINECO), (AGL2013-45922-C2-1-R).Peer Reviewe

Estado actual de la programación del riego en limero mediante medidas del estado hídrico

: En el presente trabajo se realiza una revisi´on sobre aspectos relativos a la utilizaci´on de medidas continuas del estado h´ıdrico del limonero en la programaci´on del riego. Para ello, se analiz´o, la sensibilidad de distintos indicadores del estado h´ıdrico medidos de forma continua o discontinua en las plantas, su significado fisiol´ogico, la obtenci´on de niveles de referencia de los indicadores y los primeros resultados sobre programaci´on del riego

Simulación de sistemas energéticos como metodología para el desarrollo competencial en la asignatura Ampliación de Energía

[EN] The implementation of the New Masters for the convergence to the EHEA has led to the appearance of new advanced subjects of marked technical and professional character in the new master's degrees. The main objective of this project has been the development and experimentation of free software, under Matlab environment, for the preparation of a portfolio for the development of the competences of the Master's degree in Industrial Engineering, as well as the transversal competences of the subject of Advanced Energy and Thermal Machines. The development and use of free mathematical software for the resolution of professional problems of design and analysis of real industrial energy systems will facilitate the student's work by its easy availability, but needs to be oriented on the resources and time available, as well as on the use and capabilities of the developed programs.[ES] La implantación de los Nuevos Másteres para la convergencia al EEES ha llevado aparejada la aparición de nuevas asignaturas avanzadas de marcado carácter técnico y profesional en los nuevos másteres habilitantes. El objetivo principal del presente proyecto ha sido el desarrollo y experimentación de software libre, bajo entorno Matlab, para la elaboración de un portafolio para el desarrollo de las competencias propias del título de Máster en Ingeniería Industrial, así como de las competencias transversales de la asignatura de Ampliación de Energía y Motores Térmicos. El desarrollo y empleo de software matemático libre para la resolución de problemas profesionales de diseño y análisis de sistemas energéticos industriales reales facilitará la labor discente del alumno por su fácil disponibilidad, pero necesita ser orientado sobre los recursos y tiempo disponibles, así como sobre el uso y capacidades de los programas desarrollados.Los autores de este trabajo quieren expresar su gratitud al Instituto de Ciencias de la Educación y a la Escuela Técnica Superior de Ingenieros Industriales de la Universitat Politècnica de València, por su apoyo y financiación para la realización de este PIME concedido en el curso 2016-2017 (proyecto B25). Este proyecto forma parte de los trabajos llevados a cabo por los miembros del EICE SEERI del Departamento de Ingniería Química y Nuclear.Miró Herrero, R.; Barrachina Celda, TM.; Juste Vidal, BJ.; Sanchís Arnal, R.; Palomo Anaya, MJ.; Escrivá Castells, FA.; Guardiola, C.... (2018). Simulación de sistemas energéticos como metodología para el desarrollo competencial en la asignatura Ampliación de Energía. En IN-RED 2018. IV Congreso Nacional de Innovación Educativa y Docencia en Red. Editorial Universitat Politècnica de València. 1519-1528. https://doi.org/10.4995/INRED2018.2018.8758OCS1519152

Establishing a Reference Baseline for Midday Stem Water Potential in Olive and Its Use for Plant-Based Irrigation Management

12 páginas.- 7 figuras.- 4 tablas.- 55 referencias.-Midday stem water potential (SWP) is rapidly becoming adopted as a standard tool for plant-based irrigation management in many woody perennial crops. A reference or “baseline” SWP has been used in some crops (almond, prune, grape, and walnut) to account for the climatic influence of air vapor pressure deficit (VPD) on SWP under non-limiting soil moisture conditions. The baseline can be determined empirically for field trees maintained under such non-limiting conditions, but such conditions are difficult to achieve for an entire season. We present the results of an alternative survey-based approach, using a large set of SWP and VPD data collected over multiple years, from irrigation experiments in olive orchards located in multiple countries [Spain, United States (California), Italy, and Argentina]. The relation of SWP to midday VPD across the entire data set was consistent with an upper limit SWP which declined with VPD, with the upper limit being similar to that found in Prunus. A best fit linear regression estimate for this upper limit (baseline) was found by selecting the maximum R2 and minimum probability for various upper fractions of the SWP/VPD relation. In addition to being surprisingly similar to the Prunus baseline, the olive baseline was also similar (within 0.1 MPa) to a recently published mechanistic olive soil-plant-atmosphere-continuum (SPAC) model for “super high density” orchard systems. Despite similarities in the baseline, the overall physiological range of SWP exhibited by olive extends to about −8 MPa, compared to about −4 MPa for economically producing almond. This may indicate that, despite species differences in physiological responses to low water availability (drought), there may be convergent adaptations/acclimations across species to high levels of water availability. Similar to its use in other crops, the olive baseline will enable more accurate and reproducible plant-based irrigation management for both full and deficit irrigation practices, and we present tentative SWP guidelines for this purpose. Copyright © 2021 Shackel, Moriana, Marino, Corell, Pérez-López, Martin-Palomo, Caruso, Marra, Agüero Alcaras, Milliron, Rosecrance, Fulton and Searles.In addition to the authors institutions, this research was supported by the Olive Oil Commission of California and the California Olive Committee.Peer reviewe