Es falso que la agricultura superintensiva sea sinónimo de derroche en los insumos

Artículo periodístico de una entrevista. 2 páginas.Entrevista aL investigador asegura que los trabajos científicos avalan que un olivar superintensivo consume la mitad de agua que otro tradicionalN

Water management in the Iberian península: new solutions for old problems?

9 pages, 4 figures, 2 tables, 12 references.-- XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): International Symposium on CLIMWATER 2010: Horticultural Use of Water in a Changing Climate.-- Lisboa, Portugal.The increasing demand of fresh water from different sectors puts pressure in scientists and engineers to develop more effective ways of using the available water resources. In Spain and Portugal, countries of Mediterranean climate with hot and dry summers, the allocation of water resources is especially controversial. This emphasises the need for a rational use of water. We present features and recent developments of Spanish and Portuguese water policies and some consequences on the use of land and water. We consider how social, economic and environmental problems might evolve in the expected scenarios of population growth and climatic change, and analyse the response from the scientific community to the new challenges. Finally, we pointed out that the combined efforts of professionals and users provide useful tools for satisfying the consumers demand at the same time that the environmental foot¬print is minimized.Peer Reviewe

Understanding olive adaptation to abiotic stresses as a tool to increase crop performance

22 páginas.-- 9 figuras.-- 2 tablas.-- 295 referencias.In this work we give an overview of both morphological characteristics and physiological mechanisms responsible for the high adaptability of olive to harsh environments, and how this knowledge is currently used to design new sustainable and efficient crop management practices. We first describe the biennial vegetative and reproductive cycle of olive, and how these are affected by environmental conditions. Then we address main morphological, functional and physiological traits of olive that may contribute to stress tolerance. We also summarize innovative crop management practices that have been developed from our understanding of the mechanisms of response to abiotic stresses.Peer reviewe

Relaciones hídricas suelo-planta en un olivar con riego gota a gota

44 páginas.-- 13 figuras.-- 9 tablas.-- referenicas.-- Memoria presentada en el Curso Internacional de Edafología y Biología Vegetal XXIVEn el presente trabajo se describe la metodología empleada y se dan los resultados obtenidos, así como las conclusiones que de ellos se derivan, en la labor que se ha realizado como complemento práctico del XXIV Curso Internacional de Suelos. Como es bien sabido por todos los conocedores del tema, la puesta en riego localizado de gran parte del olivar cultivado en la Cuenca Mediterránea, ha planteado numerosos interrogantes acerca del desarrollo y características productivas de las plantas en estas condiciones, así como en torno al nivel óptimo de a arte hídrico a realizar.Peer reviewe

Qué es y cómo funciona la Agencia Nacional de Evaluación y Prospectiva (ANEP). Particularidades del Área Agricultura

Pdf. de 35 diapoisitivas de la presentación hecha en los Seminarios programados por el Comité Científico del Centro de Investigación y Tecnología Agroalimentaria de AragónPeer reviewe

Influence of Partial Soil Wetting on Water Relation Parameters of the Olive Tree

A drip versus pond irrigation experiment was carried out with 30-year-old ‘Manzanilla’ olive trees planted at 7 m 5 m in an orchard in Southwest Spain. At the end of the dry season of 1998, we chose two dry-land trees, D1 and D2, and two drip-irrigated trees, I1 and I2. During the experiments, the D1 and I1 trees were pond-irrigated, increasing the soil water content to around field capacity in the whole rootzone. The D2 and I2 trees were drip-irrigated, remaining part of the rootzone in drying soil. The results showed that the ratio between the transpiration of the pond-irrigated D1 tree and that of the drip-irrigated D2 tree (D1/D2 Ep) increased from an average of 0.88 before irrigation to 1.22 fourteen days after the first water supply. For the I trees, I1/I2 Ep varied from 0.76 to 1.02 nine days after the I1 tree was pond-irrigated for the first time. Transpiration, therefore, was restricted when using a drip irrigation system which, despite supplying enough water to cover the calculated crop demand, affected a part of the rootzone only. During the drip versus pond irrigation experiment, the recovery of leaf water potential, stomatal conductance and photosynthesis rate was greater and quicker in the pond-irrigated than in the drip-irrigated trees.– Influence de l’irrigation partielle du sol sur les paramètres des relations hydriques de l’olivier. Une comparaison de l’irrigation goutte à goutte avec l’irrigation en cuvette a été conduite sur oliviers ‘Manzanilla’ âgés de 30 ans plantés à 7 m 5 m dans un verger du sud-ouest de l’Espagne. À la fin de la saison sèche de 1998, nous avons choisi deux arbres sur sol sec, D1 et D2, et deux arbres sur sol irrigué au goutte à goutte, I1 et I2. Durant les expériences, les arbres D1 et I1 ont été irrigués en cuvette, en augmentant la teneur en eau du sol jusqu’à la capacité au champ dans toute la zone racinaire. Les arbres D2 et I2 ont été irrigués au goutte à goutte, laissant une partie de la zone racinaire dans un sol se desséchant. Les résultats ont montré que le quotient entre la transpiration de l’arbre D1 irrigué en cuvette et celle de l’arbre D2 irrigué au goutte à goutte (D1/D2 Ep) a augmenté à partir d’une moyenne de 0,88 avant irrigation jusqu’à 1,22 quatorze jours après le premier apport d’eau. Pour les arbres I, I1/I2 Ep a varié entre 0,76 et 1,02 neuf jours après que l’arbre I1 ait été irrigué en cuvette pour la première fois. Par conséquent, la transpiration était réduite quand on utilisait un système d’irrigation au goutte à goutte qui, malgré l’apport d’eau suffisant pour couvrir les besoins potentiels des cultures, a affecté seulement une partie de la zone racinaire. Durant cette comparaison de l’irrigation goutte à goutte et de l’irrigation en cuvette, la récupération de la teneur en eau des feuilles, de la conductance stomatique et du taux de photosynthèse était supérieure et plus rapide pour les arbres irrigués en cuvette que pour ceux irrigués au goutte à goutte

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

Physiological and genetic response of olive leaves to water stress and recovery: implications of mesophyll conductance and genetic expression of aquaporins and carbonic anhydrase

8 páginas, 2 figuras, 18 referencias.-- XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): International Symposium on CLIMWATER 2010: Horticultural Use of Water in a Changing Climate. Lisboa, Portugal.Drought is considered to be the main environmental factor limiting photo-synthesis (AN) and, consequently, plant growth and yield worldwide. During photosynthesis, the pathway of CO2 from the atmosphere to the site of carboxylation in the chloroplast stroma has two main components: stomatal (gs) and mesophyll (gm) conductances. Both are finite and dynamic, responding to many abiotic factors, therefore reducing CO2 concentration. However, little is known about gm regulation in the short term, where a possible role of aquaporins (AQP) and carbonic anhydrase (CA) has been proposed. Five-year-old olive trees growing in 50 L pots were used to evaluate the acclimation and recovery of AN to drought and subsequent re-watering. Control trees were well-irrigated, while in stressed trees irrigation was withheld for 13 days and then resumed. We made a simultaneous analysis of the genetic expression of two AQP, OePIP1.1 and OePIP2.1, and of CA, on the one hand, and leaf water status, leaf gas exchange and shoot hydraulic conductivity on the other. This is the first time that genetic expression in olive is related to main physiological variables. Two days after withholding irrigation (a.w.i.), the gs and gm values in Stress tress were lower than in Control trees. This limited photosynthesis. Leaf water status decreased from day 4 a.w.i. Midday leaf water potential dropped from -1.2 on the day before withholding irrigation to -6.0 MPa on day 9 a.w.i. CA expression decreased during drought and there was a peak on OePIP1.1 expression on day 4 a.w.i. Leaf water status recovered in ca. 36 h after resuming irrigation. Both gm and AN did not fully recover until 46 days after rewatering. Stomatal conductance, however, did not recover in that period, probably because of an irreversible loss of shoot hydraulic conductivity. Both OePIP1.1 and OePIP2.1 peaked 36 h after rewatering. We found significant correlations between gm and both OePIP2.1 and CA expression.This work was partly supported by grants for projects AGL2005-00220/AGR and AGL-2009-11310.Peer Reviewe

Role of leaf hydraulic conductance in the regulation of stomatal conductance in almond and olive in response to water stress

11 páginas..-- 5 figuras.-- 1 tablas.-- 55 referencias.-- We thank A. Montero for field work assistance, J. Perez Hormaeche for helping us with the VD images analysis and T. Brodribb and J.M. Torres-Ruiz for discussion.The decrease of stomatal conductance (gs) is one of the prime responses to water shortage and the main determinant of yield limitation in fruit trees. Understanding the mechanisms related to stomatal closure in response to imposed water stress is crucial for correct irrigation management. The loss of leaf hydraulic functioning is considered as one of the major factors triggering stomatal closure. Thus, we conducted an experiment to quantify the dehydration response of leaf hydraulic conductance (Kleaf) and its impact on gs in two Mediterranean fruit tree species, one deciduous (almond) and one evergreen (olive). Our hypothesis was that a higher Kleaf would be associated with a higher gs and that the reduction in Kleaf would predict the reduction in gs in both species. We measured Kleaf in olive and almond during a cycle of irrigation withholding. We also compared the results of two methods to measure Kleaf: dynamic rehydration kinetics and evaporative flux methods. In addition, determined gs, leaf water potential (Ψleaf), vein density, photosynthetic capacity and turgor loss point. Results showed that gs was higher in almond than in olive and so was Kleaf (Kmax = 4.70 and 3.42 mmol s-1 MPa-1 m-2, in almond and olive, respectively) for Ψleaf > -1.2 MPa. At greater water stress levels than -1.2 MPa, however, Kleaf decreased exponentially, being similar for both species, while gs was still higher in almond than in olive. We conclude that although the Kleaf decrease with increasing water stress does not drive unequivocally the gs response to water stress, Kleaf is the variable most strongly related to the gs response to water stress, especially in olive. Other variables such as the increase in abscisic acid (ABA) may be playing an important role in gs regulation, although in our study the gs-ABA relationship did not show a clear pattern..This work was funded by the Spanish Ministry of Science and Innovation (research project AGL2009-11310/AGR). V.H.-S. benefited from a Juan de la Cierva research fellowship from the Spanish Ministry of Science and Innovation and C.M.R.-D. benefited from a FPDI research fellowship from the Junta de Andalucí

Stomatal control of water use in olive tree leaves

Little is known about the strategies used by olive trees to overcome the long dry periods typical of the areas where they are cropped. This makes it difficult to optimize the water supply in orchards. To study the control of water consumption by olive trees, measurements of leaf water potential (Ψ) and stomatal conductance to H2O (g) were made on 26-year-old Manzanillo olive trees under three irrigation treatments. The first treatment provided enough water to cover the crop water demand, the next treatment supplied one third of that rate, and the final treatment was no irrigation at all, typical of dry-farming conditions. Under conditions of high vapour pressure deficit of the air (D(a)), the olive trees prevented excessive water loss by closing their stomata. Leaves of the current year showed better stomatal control than did the 1-year-old leaves. The upper-bound functional relationships between g and D(a) and photon flux density (I(P)) were obtained by boundary-line analysis, based on a technique of non-linear least squares. Maximum values of g were observed at relatively low levels of I(p), from about 500 μmol m-2 s-1, and a proportional decrease in g with increasing D(a) was also found, at least for values of up to approximately 3.5 kPa. Higher values of g were observed in the morning than in the afternoon, for similar levels of I(P) and D(a). Unirrigated olive trees recovered quickly after the dry season, showing values of Ψ and g similar to those of irrigated trees after just two days.Peer Reviewe