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Bioactive potential of hazelnut husks was determined as a function of their cultivar source and extraction solvent. Hazelnut husks from four hazelnut cultivars (Butler, Grada de Viseu, Lansing and Morell) were picked in a hazelnut orchard at harvest and extracted with five solvents with different polarity: water, methanol, acetone, ethyl acetate and hexane. Phenolics were identified by HPLC–DAD and antioxidant activity was determined by three complementary methods: DPPH, FRAP and inhibition of lipid peroxidation. A total of 11 phenolics were identified in studied cultivars and grouped in five main classes namely, ellagitannin (ellagic acid), benzoic acids (gallic acid, protocatechuic acid and vanillic acid), flavonols (kaempferol-3,7-O-diglucoside, kaempferol-3-O-[6-acetylglucoside]-7-O-glucoside, kaempferol-3-O-[6acetylglucoside]-7-O-rhamnoside and quercetin-3-O-rutinoside), flavone (luteolin-7-O-rutinoside) and flavan-3-ol (epicatechin). Cultivar and extraction solvent influenced significantly (p

Background Various strategies are needed to mitigate the negative impact on or to increase fruit quality. The effect of spraying kaolin (K), Ascophyllum nodosum (An) and salicylic acid (SA), in trees with and without irrigation, on quality and sensorial attributes of hazelnut (Grada de Viseu cultivar) was investigated during two consecutive years (2016 and 2017) in a commercial orchard located in Moimenta da Beira, Portugal. Results The treatments affected positively the biometric parameters nut and kernel weight, length, width, thickness and volume as well as the vitamin E level, antioxidant activity and content of some individual phenolics, such as protocatechuic acid, gallocatechin, catechin and epicatechin. The levels of amino acids in hazelnut kernels decreased in all the assayed treatments, while the kernel colour and sensorial attributes were not affected by the treatments. Hazelnut physical properties (nut and kernels), chemical and phytochemical composition and antioxidant activities were positively related. Conclusions The application of K, An and SA improved the hazelnut tree response to climate change, without compromising the hazelnut chemical and sensorial quality. Furthermore, due to the similar observations for the same treatments with and without irrigation, it can be stated that K, An and SA can be efficient and cost-effective tools to mitigate summer stress in rain-fed orchards. © 2020 Society of Chemical Industry.

The caper is a shrub that adapts to harsh environments when it is established, but it presents serious difficulties in its propagation, both by cuttings and by seeds. Its seeds have low germination percentages, and germination is a very slow process. Significant increases in germination have been obtained with scarification and with the addition of gibberellic acid (GA3) to the substrate, leading to the hypothesis that they have possible physical and physiological dormancy. However, the only way to examine the water-impermeability of the cover is through imbibition analysis. This study analyzes the imbibition, viability, and germination of two seed lots, obtained in different years and evaluated immediately after their collection (FS) and after being stored (7 °C) for one month (DS) and one year (SS). The seed moisture content stabilizes from the fourth day, exceeding in all cases 31% in all three seed states tested (FS, DS and SS). This allows the germination of all viable seeds, only with the addition of GA3 to the germination substrate, without the need for scarification, so that caper seeds exclusively appear to present a physiological latency. Germination decreased in storage, even with just one month. With the GA3 addition, high germination values were obtained (up to 95% in FS).

[EN] The text presents the work developed by the EICE (educational innovation and quality team) REMYP_07, related to the acquisition of the generic outcome "Ethical, environmental and professional responsibility" by UPV graduated students. To this end, the paper develops the diagnosis of the current situation in four engineering bachelor programs taught at this university . Based on the diagnosis, the work focuses in actions to improve the inclusion of this competence throughout the curriculum to guarantee its acquisition by students who complete their studies., [ES] En el texto se presenta el trabajo desarrollado por el EICE (equipo de innovación y calidad educativa) REMYP_07, relacionado con la adquisición de la competencia transversal “Responsabilidad ética, medioambiental y profesional” por parte de los alumnos egresados de la UPV. Para ello se indica como se ha realizado el diagnóstico de la situación actual en cuatro grados impartidos en dicha universidad y a partir del diagnóstico se muestran las acciones a llevar a cabo para mejorar la inclusión de dicha competencia a lo largo del plan de estudios de manera que se pueda garantizar su adquisición por parte de los alumnos egresados.

[EN] This paper presents a study on the development of the cross-curricular learning outcome (CCLO) "Ethical, environmental and professional responsibility" for students of different Bachelor's Degrees taught at Universitat Politecnica de Valencia (Spain). The work involved in the development of this learning outcome entails great complexity, given the double dimension of responsibility that it involves. At the end of their training at the university, students are expected to show ethical, environmental, and professional responsibility towards themselves and others. Interviews have been conducted with lecturers who work and assess this outcome in their subjects, most/all of them related to science and engineering. The objective was to identify the learning approach used in the different subjects to guarantee the acquisition of this CCLO by the students. A focus group has also been carried out with students to determine the importance they give to this learning outcome, and to know their degree of satisfaction with the training received. The methodology used to obtain the data from lecturers and students and to process the information to get a precise diagnosis is fully described in the paper. Results are satisfactory to some extent: most of the lecturers carry out appropriate activities and most students achieve the expected proficiency level. Finally, recommendations are given to improve the development of this cross-curricular learning outcome., This innovative educational project and the APC of this paper were funded by Universitat Politecnica de Valencia, through the project PIME/20-21/219 "Evaluacion del nivel de adquisicion de la CT07 Responsabilidad etica, medioambiental y profesional en los estudios de grado de la UPV. Propuestas de mejora".

Water scarcity is seriously affecting agricultural production, especially in arid and semi-arid areas. Therefore, there is increasing interest in improving water productivity in agriculture. This research aims to study the effects of deficit irrigation on the productive response of sweet pepper plants. Nine deficit irrigation strategies were assayed during two seasons (2017 and 2018) in a randomised complete block design with three replicates. These irrigation strategies consisted of applying 100%, 75% and 50% of the irrigation water requirement (IWR) during the entire growing period (continued deficit irrigation) or applying 75% or 50% of the IWR during one of the following stages (regulated deficit irrigation): vegetative growth, fruit setting, and harvesting. Pepper plants cultivated under deficit irrigation reduced fruit biomass and indicators of plant water status. Applying water deficits during the vegetative growth and fruit-setting stages had minimal effects on the marketable yield but with minimal water savings. Irrigating pepper plants with 75% or 50% of the IWR during the entire crop cycle or with 50% of the IWR during harvesting resulted in a high incidence of fruits affected by blossom end rot, which in turn, led to a drastic reduction of the marketable yield in relation to fully irrigated plants (− 36%, − 55% and − 44%, respectively). These strategies also recorded the highest soluble solid and phenolic contents. Reducing the water applied to 75% of the IWR at harvesting led to a yield reduction (− 19%) but with important water savings (21%) and acceptable levels of soluble fruit solids and phenolic compounds.

Chufa, also known as tigernut, is a typical irrigated crop in Valencia, Spain, where it is traditionally cultivated for its tubers. Its cultivation uses large amounts of water, in the order of 10,000 m3 ha(‑1) year‑1. During the last years, the research team in which this study has been developed, has carried out several studies leading to improve the irrigation water use efficiency in chufa. Although these improvements are considerable, they are not definitive, as the water requirements of the crop are still unknown. To know these needs, it would be recommended to determine the crop evapotranspiration (ETc). The experiment was carried out on an experimental plot of the Universitat Politecnica de Valencia, included in the traditional cultivation area. This plot includes a lysimetric station (Smart Field Lysimeter) which allows determining the daily ETc. In addition, the plot is equipped with a meteorological station, which provides the necessary parameters for the determination of the daily reference crop evapotranspiration (ETo) through the FAO-56 Penman-Monteith method. Relating the values of ETc and ETo, the crop coefficient (Kc) values corresponding to the different growth stages, has been estimated from the data obtained during the crop cycle. Considering the crop development, the length of the four growth stages were considered as 21, 76, 43 and 29 days for initial, development, mid-season and late season stages, respectively. The single Kc values for the initial, mean and end of the late season stages were established as 0.25, 1.43 and 0.75, respectively. The use of these Kc values will allow adjusting irrigation water doses to water requirements, thus reducing the volume of water applied and improving the irrigation application efficiencies in chufa crop.

[EN] Response surface methodology (RSM) was chosen to optimize the influence of solvent pH and relative proportion, and time of extraction, regarding polyphenols and radical scavenging capacity of almond (Prunus dulcis (Mill.) D.A. Webb) by-products (hulls, shells, and skins) from an almond orchard located in the North of Portugal (Lousa, Torre de Moncorvo). The RSM model was developed according to a Box-Behnken design and the optimal conditions were set for pH 6.5, 250.0 min, and 90.0% of food quality ethanol, pH 1.5, 235.0 min, and 63.0% ethanol, and pH 1.5, 250.0 min, and 56.0% ethanol for hulls, shells, and skins, respectively. The optimal conditions were obtained applying spectrophotometric techniques because of their versatility, while the chromatographic profile of extracts obtained when applied the optimal conditions indicated the presence of 3-caffeoylquinic acid, naringenin-7-O-glucoside, kaempferol-3-O-glucoside, isorhamnetin-3-O-rutinoside, isorhamnetin-3-O-glucoside, and isorhamnetin aglycone in hulls and skins. The model designed allowed the optimization of the phenolic extraction from almond by-products, demonstrating the potential of these materials as sources of antioxidant compounds with potential industrial, pharmaceutical, and food applications., IP received financial support from the FCT-Portuguese Foundation for Science and Technology (SFRH/BD/52539/2014), under the Doctoral Programme BAgricultural Production Chains-from fork to farm (PD/00122/2012). RDP was supported by a Postdoctoral Contract (Juan de la Cierva de Incorporacion ICJI-2015-25373) from the Ministry of Economy, Industry and Competitiveness of Spain. This work is supported by the National Funds by FCT-Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2019.

The common fig (Ficus carica L.) is a fruit species traditionally cultivated in coastal Croatia. After some years of being of low commercial value, the interest in fig consumption and cultivation in this region seems to start following the increasing trend. One way of promoting fig consumption is to identify the varietal sensory properties, intending to match the consumer preferences. For this reason, the goal of this study was to evaluate sensory properties and pomological characteristics of fresh fruits of five dark (‘Šaraguja’, ‘Miljska’, ‘Crnica’, ‘Piombinese’, ‘Nero Rosso’) and three light-coloured (‘Petrovača bijela’, ‘Tiger’, ‘San Martino’) skin fig varieties, grown in Croatia. Figs were harvested from 5-years old trees in the fig experimental orchard located in Istria County (Croatia). Significant differences were observed for the properties of appearance, odour, flavour, and taste. Fresh fruits of varieties 'Šaraguja' and 'Tiger' reached the highest scores for the intensity of taste, fig odour, and flavour, compared to all the others. The highest values regarding fruit thickness and width were recorded from the variety 'Petrovača bijela', lenght from the variety 'Šaraguja', while 'San Martino' variety had the fruits of biggest weight. The variety 'Miljska' displayed the lowest values in all the observed pomological parameters. The importance of the pomological description and observation of sensory parameters of fresh figs lies in permitting the producers to decide the potential of each variety based on consumer preferences., Smokva (Ficus carica L.) je voćna vrsta koja se tradicionalno uzgaja u primorskoj Hrvatskoj. Nakon nekoliko godina niske komercijalne vrijednosti ove kulture, čini se da interes za potrošnjom i uzgojem smokava u ovoj regiji počinje rasti. Jedan od načina promicanja konzumacije smokava je prepoznavanje sortnih senzornih svojstava, sa ciljem usklađivanja sklonosti potrošača. Iz tog razloga cilj ovog istraživanja bio je procijeniti senzorna i pomološka svojstva svježih plodova pet crnih ('Šaraguja', 'Miljska', 'Crnica', 'Piombinese', 'Nero Rosso') i tri bijele ('Petrovača bijela', 'Tiger', 'San Martino') sorte smokve uzgojene u Hrvatskoj. Smokve su ubrane s pet godina starih stabala u pokusnom smokviku u Istarskoj županiji (Hrvatska). Uočene su značajne razlike u svojstvima izgleda, mirisa, arome i okusa. Svježi plodovi smokve sorti ‘Šaraguja’ i ‘Tiger’ postigli su najviše ocjene za intenzitet okusa, mirisa i arome smokve u odnosu na sve ostale sorte. Najviše vrijednosti debljine i širine ploda utvrđene su za sortu 'Petrovača bijela', širine za sortu 'Šaraguja', dok je sorta 'San Martino' imala plodove najveće mase. Sorta 'Miljska' imala je najmanje vrijednosti za sva istraživana pomološka svojstva. Važnost pomološkog opisa i istraživanja senzornih svojstava svježih smokava leži u omogućavanju proizvođačima da odluče o potencijalu svake sorte na temelju preferencija potrošača.

[EN] Chufa is a typical crop in Valencia, Spain, where it is cultivated in ridges with furrow irrigation. It uses large volumes of water, and thus, different studies have been undertaken to maximize irrigation water use efficiency to obtain important water savings. Particularly, different values for turning water on, considering the basis of volumetric soil water content were analysed in drip irrigation. It was reported that starting each irrigation event when the volumetric soil water content dropped to 90% of the field capacity resulted in the best yield, and the best irrigation water use efficiency was obtained when it dropped to 80% of the field capacity. However, these results may be improved by defining the optimum criteria for turning water off, which is the aim of the present research. This investigation, conducted in 2015, 2016 and 2017, analises the productive response of the drip irrigated chufa crop, determining the yield and the irrigation water use efficiency. The volumetric soil water content was monitored using multi-depth capacitance probes, with sensors at 0.10, 0.20 and 0.30 m below the top of the ridge. Each irrigation event started when the volumetric soil water content at 0.10 m dropped to 85% of field capacity. Three irrigation strategies were considered. T1: each event resulting in water being turned off when the sum of the volumetric soil water content values that were measured at 0.10, 0.20 and 0.30 m reached the corresponding field capacity value; T2: turning water off in each event when the volumetric soil water content values that were measured at 0.20 m reached the corresponding field capacity value; and T3: each irrigation event applying 8.5 mm in 2015 and 2016, as well as 9.8 mm in 2017. Overall, the T2 strategy resulted in the largest yield, and T3 resulted in the highest irrigation water use efficiency in 2015 and 2016. The average tuber weight and dry matter content did not differ between the irrigation strategies., This work was supported by the Generalitat Valenciana [GV/2017/037].

[EN] Almond (Prunus dulcis (Mill.) D. A. Webb) production keeps an increasing trend worldwide, leading to augment in generation of harmful by-products that should be valorized as a source of bioactive phytochemicals with application in the development of new added-value products. The assessment of almond hulls and skins on their (poly)phenolic composition was developed upon two seasons, under five irrigation regimes, regarding total phenolics, flavonoids, and ortho-diphenols, as well as individual phenolic compounds analyzed by High Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). As functional tests, extracts were assessed on their radical scavenging activity in vitro and reducing power, and screened on their antimicrobial activity against multidrug resistant bacterial pathogens. The phenolic profile and antioxidant activities were evaluated in blanching water as well. Naringenin-7-O-glucoside and isorhamnetin-3-O-rutinoside were the most abundant phenolics in almond hulls and skins. Influence of irrigation treatments and season on phenolic content differed among by-products; hulls being more influenced by irrigation and skins by the agro-climatic conditions. The synthesis of individual phenolics was more influenced by season than treatment. According to the chemical and biological correlations, the presence of (poly)phenols seems to be responsible for the antioxidant and antimicrobial properties revealed. The knowledge generated upon the present work contributes to understand the variability of almond by-products composition attributable to seasonal and irrigation conditions, and to envisage valorization alternatives for these under explored residues and blanching water., IP acknowledges the financial support provided by the FCT-Portuguese Foundation for Science and Technology (SFRH/BD/52539/2014), under the Doctoral Programme Agricultural Production Chains from fork to farm (PD/00122/2012). This work was also supported by National Funds by FCT - Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2019. RDP was supported by a Postdoctoral Contract (Juan de la Cierva de Incorporación ICJI-2015-25373) from the Ministry of Economy, Industry and Competitiveness of Spain.

Water is an essential resource for food production, as agriculture consumes close to 70% of the total freshwater, and its shortage is becoming critical in arid and semiarid areas of the world. Therefore, it is important to use water more efficiently. The objectives of this project are to determine the productive response and the irrigation water use efficiency of seedless watermelon to three irrigation management strategies over two growing seasons. This was done by applying 100, 75 and 50% of the irrigation water requirements (IWR) the first year, in the second year added six additional treatments, of which three treatments were regulated deficit irrigation with 75% IWR during the vegetative growth, fruit development and fruit ripening stages, and the other three treatments were with 50% IWR during the same stages. The exposure of watermelon plants to severe deficit irrigation resulted in a reduction in dry biomass, total and marketable yield, average fruit weight, fruit number and harvest index, and without improvement of marketable fruit quality. The fruit ripening was the less sensitive stage to water deficits. Relative water content and cell membrane stability index decreased as the water deficit increased. Irrigation water use efficiency decreased to a lesser extend during the fruit ripening stage than when water restriction were applied during different growth stages. If water is readily available, irrigating with 100% of water requirements is recommended, but in the case of water scarcity, applying water shortage during fruit ripening stage would be advisable.

[EN] The almond tree is generally recognized as drought-tolerant, though it depends on water resources to achieve high yields. During the summer months of two consecutive years, several physiological and biochemical parameters were observed, to understand the almond tree's seasonal sensitivity and behavior under different irrigation strategies based on crop evapotranspiration (ETc): T100 optimal water requirement regime (applying 100% ETc); T70 and T35 sustained deficit irrigation regimes (applying 70% and 35% ETc); T100-35 regulated deficit irrigation regime (reducing the application to 35% ETc during fruit filling stage); and TO (rainfed). The total leaf chlorophyll and carotenoid reduction in TO and T35 treatments was significant compared to T100-35. Leaf soluble proteins and total soluble sugar contents were significantly higher in non-irrigated trees compared to other treatments, while the starch content showed the opposite trend. Rainfed trees were under obvious water stress, displaying the lowest values for relative water content (RWC), stomatal conductance (gs), photosynthetic rate (A), and transpiration rate (E), and the highest for intrinsic water use efficiency (A/gs). Plant hormones (ABA and IAA) generally accumulated more in non-irrigated trees. The almond tree has been confirmed as a drought-tolerant species, and when water is scarce, reducing the water application to 35% ETc during fruit filling stage, results in no yield losses, and the plant status remains unstressed. However, to get the maximum crop potential, in years and areas where water is not restricted, full irrigation requirements have been shown to boost almond tree performance., IP acknowledges the financial support provided by the FCT-Portuguese Foundation for Science and Technology (SFRH/BD/52539/2014), under the Doctoral Programme "Agricultural Production Chains -from fork to farm" (PD/00122/2012). This work was also supported by National Funds by FCT -Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2019 and by the project PRODER "Estrategias Integradas para o aumento da produtividade da amendoeira em Tras-os-Montes, no 54611. 2014 a 2018. The authors wish to acknowledge the help and support provided during field and laboratory work by Ana Monteiro, Cristiana Teixeira, Helena Ferreira, Ivo Oliveira, Linton Dinis, Sara Bernardo, Silvia Afonso, and Silvina Morais, and thank Joao Santos and Chenyao Yang for help with climate data.

[EN] This article analyzes the experience of using different collaborative work tools to dynamize the tasks that help to acquire and improve key competence ethical, environmental and professional responsibility. The selected tools are integrated in the learning management system (LMS), PoliformaT, of the Universitat Politècnica de València. In particular, we have worked with the forum and the wiki, and the blog which is integrated in Poliblogs. In this experience three Bachelor degrees and a Master degree of engineering and life sciences have been involved: Bachelor's Degree in Environmental Sciences, Bachelor's Degree in Rural and Agrifood Engineering, Bachelor's Degree in Mechanical Engineering and Master's Degree in Design Engineering. The results show that the students value the experience satisfactorily thanks to the virtual interaction with other colleagues and they highlight the extra motivation offered by the use of these tools. It is noteworthy that to obtain good results there are two key elements: 1) clear rules of operation and evaluation and 2) high participation of the teacher as moderator., [ES] En el presente artículo se analiza la experiencia de uso de distintas herramientas de trabajo colaborativo para dinamizar las tareas que ayudan a adquirir y mejorar la competencia transversal responsabilidad ética, medioambiental y profesional. Las herramientas seleccionadas están integradas en la plataforma de gestión del aprendizaje, poliformat, de la Universitat Politècnica de València. En particular hemos trabajado con el foro y la wiki, además de con el blog integrado en Poliblogs. En esta experiencia han participado tres titulaciones de Grado y un Máster de ingeniería y ciencias de la vida: Grado en Ciencias Ambientales, Grado en Ingeniería Agroalimentaria y del Medio Rural, Grado en Ingeniería Mecánica, y Máster Universitario en Ingeniería del Diseño. Los resultados obtenidos muestran que el alumnado valora satisfactoriamente la experiencia gracias a la interacción virtual con otros compañeros y destacan la motivación extra que les ofrece el uso de estas herramientas. Es destacable que para la obtención de buenos resultados hay dos elementos clave: 1) Normas claras de funcionamiento y evaluación y 2) Alta participación del profesor como moderador.

Field experiments were performed for two growing seasons in Spain under Mediterranean conditions to evaluate the response of onion growth, plant water status, bulb yield, irrigation water use efficiency (IWUE), and gross revenue to regulated deficit irrigation strategies (RDI). Seven irrigation treatments were utilized, including the application of 100% irrigation water requirements (IWR) during the entire growing season and the application of 75% or 50% of the IWR during one of the following growth stages: the vegetative growth, bulbing, and bulb ripening stages. The deficit irrigation strategies tested decreased marketable yields to greater or lesser extents, therefore, if water is readily available, full irrigation would be recommended. The RDI with 50% of the IWR during the bulb ripening stage led to important water savings (22%) and to slight decreases in yield (9%), improving IWUE (20%) compared with full irrigation, and this strategy can be recommended under a severe water shortage. A satisfactory bulb yield was obtained with RDI with 75% of the IWR during the bulb ripening stages, resulting in a lower reduction in yield (4%) and in an increased IWUE (9%), this strategy is an advisable strategy for onion production under a mild water shortage in Mediterranean conditions.

Some cultivar radishes of ‘Daikon’ or oriental radish (Raphanus sativus L. var. longipinnatus L.H. Bailey) have largely replaced in Spain the cultivation of turnips (Brassica napus L.). Market acceptance of these taproots can be affected by the incidence of various physiological disorders, such as the cracking, hollowness, malformation and the emission of secondary roots. We used two Korean cultivars, ‘Spring Favor’ and ‘Spring White’ in greenhouse cultivation in two production cycles, autumn-winter and spring season, in containers of 25 L filled with three substrates, perlite B12, coir dust and sand. In these experiments, designed according to a factorial program, we tried to establish the influence of cultivars, maturity stages and growing media on the incidence of mentioned physiological disorders, commercial production, taproot shape and size, and leaves dry weight. ‘Spring White’ was more susceptible to cracking and malformation than ‘Spring Favor’ while ‘Spring Favor’ showed a greater susceptibility to hollowness and secondary roots emission, ‘Spring White’ taproots were longer and less wide than ‘Spring Favor’. Over-maturity taproots did not influence on the hollowness and malformation. Among the three used substrates, perlite behaved worse in the incidence of almost all studied physiological disorders, while it seems that sand and coir dust did not adversely affect them. No many significant interactions were detected between cultivars x substrates.

[EN] The artichoke crop in Spain is mainly reproduced by vegetative propagation, using cuttings, stumps or stalks, the cultivar ‘Blanca de Tudela’ with green heads being the most important. In the south of Valencia and Murcia Communities the cultivar ‘Violet de Provence’ with purple heads is also produced, to be exported to France. The vegetative propagation presents physiological, pathological and financial drawbacks. For that reason this work analyzes the viability of new seed cultivars of artichoke. The agronomic behaviour of 20 seed propagated cultivars/ lines was studied, eleven of them with green heads and nine with purple heads, and using ‘Blanca de Tudela’ and ‘Violet de Provence’ as respective controls, being both asexually propagated cultivars. Seeds were sown on 8 June 2010 and transplanting was carried out on 21 July 2010, in open-field conditions in Paiporta (Valencia, Spain). The highest early yield in green head cultivars/lines was achieved by NUN 4011 (0.51 kg m-2) not differing from that obtained in ‘Blanca de Tudela’ (0.4 kg m-2). The highest early yields in purple head cultivars/lines was obtained by NUN 4146 (0.44 kg m-2), not showing differences either from the control ‘Violet de Provence’ (0.4 kg m-2). At end of harvest, the greatest cumulative yield in the green head cultivars/lines was reached by ‘NUN 4011’ (2.75 kg m-2); while among purple head cultivars/lines it was achieved by ‘Opal’ (2.24 kg m-2). Final yield in both green and purple head control cultivars was lower than those for the most productive seed propagated cultivars/lines. Both ‘NUN 4011’ and ‘Opal’ excelled by their low level of non-marketable yield and good quality of artichoke heads., Thanks to Conselleria de Agricultura Pesca y Alimentación de la Comunidad Valenciana for the financial assistance in this study, which is included in the developed research for Programa Hortofrutícoloa, an I+D+i project.

In the last two years the Universitat Politècnica de València (UPV) has implemented the evaluation of key transversal competences in its degrees. The objective is to offer an added value both for UPV s graduates and their employers. Nowadays, labour market is demanding not only professional skills but also personal and transversal competences development. However, evaluating these skills may require evaluation methods and techniques different to traditional ones. The authors have worked with gamification tools to help assessing student s performance in Ethical, environmental and professional responsibility skill. The experiences described have been developed in the frame of an Innovative Educational Project Improvement during the academic years 2014/2015 and 2015/2016. The aim of this paper is to compare the performance of two gamification applications, Socrative and Quizbean, for evaluating the above mentioned skill. Both applications can be used in the classroom with different devices such as laptops, tablets or mobile phones, and are based on creating questionnaires. These applications also share other characteristics such as high number of questions allowed, relatively high number of students in the classroom, instant results, etc. Socrative was used in Thermodynamics and Chemical Kinetics course in the first year of the Bachelor s degree in Biotechnology. Quizbean was used in Groundwater management subject in the fourth year of the Bachelor s degree in Environmental Sciences. To increase student motivation, game rules were included to encourage competition. The questionnaires were designed and classified according to 3 possible levels of acquisition of the key competence, these levels are fully described in a specific rubric that was explained beforehand to the students. Both applications performed successfully and the specificities of each gamification tool are described in the results. Students were satisfactorily involved in the activity, and some examples are included to show different levels of competence acquisition., The authors would like to thank the Vice-Rectorate for Studies, Quality and Acreditation of the Universitat Politècnica de València for funding the lnnovation and Educational Improvement Project A005: “Experiencia piloto de evaluación en distintas titulaciones de la UPV de la competencia transversal UPV Responsabilidad ética, medioambiental y profesional”

This paper presents information on all aspects of the biology of Cyperus esculentus L. (yellow nutsedge) and deals with its taxonomy, morphology, genetic diversity, distribution, habitat requirements, ecology and life cycle, with special emphasis on uses and cultivation, history of introduction, impact and management in Europe. C. esculentus is a tuber geophyte and most likely originates from the Mediterranean and Southwest Asia. It is a variable plant and four wild-type varieties are presently recognized, in addition to a cultivated form. C. esculentus reproduces primarily by its underground tubers, although abundant seeds are produced. In temperate climates, tubers usually sprout in late spring and the plant withers at the beginning of the winter. C. esculentus is only cultivated in the Valencia region in Spain. Invasion foci emerged across Europe at the beginning of the 1980s and at present, C. esculentus is most abundant on arable land and in ruderal habitats, followed by riverine vegetation. In heavily infested regions of Europe, C. esculentus causes substantial yield losses in field crops and although different management strategies are available, C. esculentus remains difficult to control.

[EN] A two-year study was conducted to analyze the yield and irrigation water-use efficiency of chufa crop in response to planting configuration and drip irrigation scheduling as a function of the volumetric soil water content. The planting configurations were: beds with three plant rows and three driplines (B3), beds with three plant rows and two driplines (B2), beds with two plant rows and two driplines (b), and ridges (R). The yield was affected by the planting configuration; greater yields were obtained in beds (on average 2.36 kg m−2) than in R (2.14 kg m−2). Considerably less irrigation water was applied in R and in B2 than in beds B3 and b. The irrigation water-use efficiency was affected by the planting configuration in the same line that the irrigation water was applied, with greater values being obtained in B2 (7.58 kg m−3) than in the R (6.63 kg m−3), which in turn was higher than B3 (5.92 kg m−3) and b (5.69 kg m−3). These values of the irrigation water-use efficiency were considerably higher than those obtained in previous experiments (based on the volumetric soil water content in the ridges). Neither the yield nor the average tuber weight were affected by the position of the different planting rows in the bed., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain.

This study evaluated growth, yield, quality and quercetin concentration in response to planting density and deficit irrigation of onion (Allium cepa L.) in southwest Texas over two years. Onion seeds (cv. TG 1015) were direct seeded in the field on November 11, 2007 and October 30, 2008 at two planting densities (PD), 397 (standard PD) and 494 (high PD) ×1000 seeds•ha-1. Three irrigation rates were imposed after plants were fully established, 100, 75, and 50% crop evapotranspiration rates (ETc). Overall, there were consistent trends for bulb size, yield and quality parameters in both seasons. The number of bulbs and total marketable yields significantly increased (7-14%) at high PD; however, high PD decreased bulb size as compared to standard PD. Deficit irrigation at 50% ETc decreased most growth components. Similarly 50% ETc rate decreased marketable yield by 27% and 19% in 2008 and 2009, respectively; while 75% ETc decreased only 8% in 2008 and 13% in 2009. Soluble solids content, pungency, and quercetin were not affected by irrigation or planting density in both seasons. These results suggest that growers in water-limited conditions could adjust planting densities and implement water conserving practices (e.g., 75% ETc rate) to target high-price bulb sizes without reducing flavor or nutritional components.

This study was designed to analyze the effects, over two consecutive years (2006-2007), of accelerated ageing (AA) on the germination of caper (Capparis spinosa L.) seeds of cultivar 'Comun'. Seeds were aged for 24, 48, 72 or 96 h at 45°C. The effects of ageing were evaluated via standard germination tests, performed in closed Petri dishes in a growth chamber. Germination data were fitted to the logistic function, and calculations were made for the maximum germination percentage (A), the time to reach 50% of final germination (β/k) and the mean relative cumulative rate (k/2). The results show that AA improved germination, especially in terms of significantly higher A values (higher than 90%) compared to non-aged seeds (53% on average), and lower β/k (lower than 68 days) than non-aged seeds (89 days on average), while k/2 was not significantly affected. Neither A nor k/2 were affected by ageing time; however, β/k significantly decreased with ageing time from 24 to 96 h, following a negative linear pattern. Year did not affect significantly any of the studied germination parameters.

Cape gooseberry (Physalis peruviana L.) is a solanaceous plant. The growth and time-course of nutrient accumulation of the plant and its partitioning between roots, stems, leaves, and fruits were examined. The study was conducted analyzing two nutrient solutions in soilless culture under greenhouse conditions during two consecutive seasons. The macronutrient contents were analyzed. On average, the yield was 8.9 t.ha(-1). Growth of the plant until 90 d after transplanting obeys an exponential function of time and the relative growth rate for this period was determined. Nitrogen (N) was the element that showed the highest concentration, corresponding to leaves (4.67%), followed by potassium (K) in stems (4.46%). The highest accumulations of N, phosphorous (P), calcium (Ca), and magnesium (Mg) were found in leaves and of K in the stems. Potassium showed the highest nutrient accumulation (29 g.plant(-1)) and the highest specific uptake rate.

1) Introduccion. Objetivo del trabajo. Siguiendo la linea de trabajo dirigida a complementar y diversificar la Horticultura Valenciana, se ha llevado a cabo el estudio agronomico de la adaptacion de Physalis peruviana L. a condiciones de cultivo bajo invernadero en la zona mediterranea. En la actualidad uno de los factores mas restrictivos en la produccion horticola es la disponibilidad de agua de riego, por ese motivo, resulta de gran importancia conocer cuales son las necesidades del cultivo, y como afecta a la produccion y calidad de los frutos, la utilizacion de diferentes dosis de riego. En lo que respecta a la fertilizacion, el nitrogeno es un elemento fundamental para asegurar un adecuado desarrollo de cualquier cultivo horticola, si bien un abonado excesivo puede producir un desarrollo vegetativo exuberante que actue en detrimento de la produccion, e inducir una mayor susceptibilidad a distintas fisiopatias. El “cracking” o rajado de los frutos es una fisiopatia que se manifiesta en forma de grietas longitudinales en la superficie de los frutos. En el cultivo de Physalis , es uno de los factores que mas condicionan la produccion en todas las zonas de cultivo, llegandose a porcentajes de frutos afectados de entre el 30 y el 50 %. El objetivo del presente experimento es evaluar la respuesta de las plantas de Physalis a la aplicacion de diferentes dosis de riego y soluciones nutritivas, tanto en terminos productivos (cantidad producida y calidad de la cosecha) como de desarrollo vegetativo. 2) Descripcion del tema y del proceso de ejecucion del trabajo El semillero se realizo el 4 de febrero de 2013. La plantacion definitiva en los invernaderos tipo Venlo de la Universitat Politecnica de Valencia se produjo el 11 de abril de 2013, en macetas de 35 cm de O (25 L), rellenas de perlita (1 planta por contenedor). La aportacion de nutrientes se hizo a traves de fertirrigacion, con un sistema de riego localizado (1 gotero de 2 L·h -1 por planta para la dosis de riego D1, y 2 goteros de 2 L·h -1 para la dosis D2). Se eligio un diseno de bloques al azar con 2 dosis de riego (D1 y D2) y 3 soluciones nutritivas (S1, S2 y S3) (Tabla 1) y 3 U.R. (unidades de repeticion) de 5 plantas cada una; para un total de 18 U.R. y 90 plantas. Las dosis de riego empleadas fueron: - D1 (dosis baja): 50% ETo - D2 (dosis media): 100% ETo Mensualmente, se tomaron medidas de la altura de la planta y del diametro del tallo. Al final del cultivo se tomo el peso fresco y seco de la parte aerea. Los frutos se clasificaron en comerciales (sin “cracking”), cc (“cracking” concentrico), cl (“cracking” longitudinal) y cc+cl (presentan simultaneamente ambos tipos) Los analisis cualitativos consistieron en medidas de firmeza (penetrometro) con aguja de 3 mm, oBrix (refractometro) y acidez (AT) (valoracion con NaOH 0.1N). El inicio de la recoleccion se produjo el dia 11 de julio de 2013 extendiendose hasta el 10 de febrero de 2014, con pases semanales. 3) Conclusiones Con la dosis de riego D1, la produccion total aumento al incrementarse el contenido de nitratos de las soluciones nutritivas, ajustandose a una recta (p

[EN] Currently, the advances in information and communication technologies (ICTs) offer new tools to implement active teaching-learning methodologies. Gamification is a new teaching strategy, capable of implementing active methodologies in the classroom that can be facilitated by the use of ICTs. It allows the use of game mechanics in non-recreational environments to achieve educational objectives and it improves students’ motivation. This has led to the introduction in the classroom of computer applications (or apps), computer programs and tools designed to allow undertaking various types of work. The wide variety of apps available for gamification complicates their choice, not only for their topic, but also for their technology (mobile devices, tablets, and personal computers). Furthermore, although there are different apps which were not initially designed for their use in education, they can be used for this purpose. In response to this diversity, this article presents a review of different gamification experiences at higher education level. The main goal of this article is to provide a resource guide to the people interested in these apps, [ES] Actualmente los avances en tecnologías la información y la comunicación (TICs) ofrecen nuevas herramientas para implementar metodologías de enseñanza-aprendizaje activas. Por otra parte la gamificación permite el empleo de mecánicas de juego en entornos no lúdicos para alcanzar objetivos docentes y mejorar con ello la motivación de los alumnos. Se trata pues de una nueva estrategia docente, en auge en la docencia universitaria, capaz de implementar metodologías activas en el aula que puede ser facilitada por el uso de TICs. Esto ha dado lugar a la introducción en el aula de aplicaciones informáticas o apps (del inglés applications), programas informáticos diseñados como herramientas para permitir a un usuario realizar diversos tipos de trabajos. La gran variedad de apps disponibles para la gamificación complica su elección, tanto como por su temática acomo por la tecnología utilizada (dispositivos móviles, tabletas y ordenadores personales). Además, hay distintas apps que aunque no fueran concebidas inicialmente para la gamificación pueden ser utilizadas para este fin. En respuesta a esta diversidad, el presente artículo realiza una revisión de las apps utilizadas en experiencias docentes de gamificación en el ámbito universitario. El objetivo es facilitar a los profesores interesados en desarrollar actividades de gamificación mediante TICs una guía de recursos.

[ES] La evapotranspiración (ET) es la combinación de dos procesos separados por los que el agua se pierde a través de la superficie del suelo por evaporación, y por otra parte, mediante transpiración del cultivo. Los factores relacionados con el cultivo y su manejo fueron englobados en la función empírica Kc = ETc/ET0, donde ETc es la evapotranspiración de cultivo y ET0 es la evapotranspriación de referencia. Actualmente el método de Penman-Monteith es el recomendado por la FAO y la ASCE (American Society of Civil Engineers) para determinar la ET0, requiriendo gran cantidad de parámetros climáticos como radiación, temperatura del aire, humedad atmosférica y velocidad del viento. Existen otros modelos de cálculo (como los propuestos por Hargreaves, Samani y Priestley-Taylor) más sencillos, que son evaluados en este trabajo, utilizando como caso de estudio el jardín de la Universitat Politècnica de València. Adicionalmente los métodos se recalibran, adaptando sus coeficientes empíricos por comparación con la ecuación de Penman-Monteith. Finalmente se realiza un balance de humedad contrastándolo con los valores obtenidos por medido de sondas FDR. Así se ha podido aproximar un valor del coeficiente Kj para el caso de estudio, que relaciona ET0 y ETc en el caso singular de un jardín., Este trabajo ha sido financiado por la ayuda SP20120823 del Programa de Apoyo a la Investigación y Desarrollo (PAID-06-12) del Vicerrectorado de Investigación de la Universitat Politècnica de València a través del proyecto “Estrategias para el ahorro de agua y energía en jardinería Mediterránea. Comparación de las necesidades de riego determinadas con modelos agro-hidrológicos y sondas de humedad de suelo e integración en la gestión hidráulica”.

Cultivated nutsedge is a common crop in Valencia (Spain). The aim of this research, which was conducted over two consecutive years, was to compare the productive response of the nutsedge crop with drip irrigation and traditional furrow irrigation, calculating the yield and the irrigation water use efficiency (IWUE). The volumetric soil water content was monitored with capacitance probes. Four irrigation strategies were considered: three in drip irrigation [D70, D80 and D90 with refill points at 70, 80 and 90 % of the field capacity, respectively] and one in furrow irrigation (refill point at 60 % field capacity); in the second year, the irrigation management was automated. On average, strategy D90 produced the highest yield and D70 the lowest, while the highest IWUE was obtained with D80 and the lowest with furrow irrigation. Considering the automation of irrigation management, strategy D90 led to the highest yield and to the highest IWUE., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain.

[EN] Almond is characterized by its high nutritional value; although information reported so far mainly concerns edible kernel. Even though the nutritional and commercial relevance of the almond is restricted to almond meat; to date; increasing attention has been paid to other parts of this fruit (skin; shell; and hull); considered by-products that are scarcely characterized and exploited regarding their properties as valuable sources of bioactive compounds (mainly represented by phenolic acids and flavonoids). This lack of proper valorization procedures entails the continuation of the application of traditional procedures to almond residues that nowadays are mainly addressed to livestock feed and energy production. In this sense; data available on the physicochemical and phytochemical composition of almond meat and its related residues suggest promising applications; and allow one to envisage new uses as functional ingredients towards value-added foods and feeds; as well as a source of bioactive phytochemicals to be included in cosmetic formulations. This objective has prompted investigators working in the field to evaluate their functional properties and biological activity. This approach has provided interesting information concerning the capacity of polyphenolic extracts of almond by-products to prevent degenerative diseases linked to oxidative stress and inflammation in human tissues and cells; in the frame of diverse pathophysiological situations. Hence; this review deals with gathering data available in the scientific literature on the phytochemical composition and bioactivity of almond by-products as well as on their bioactivity so as to promote their functional application., This work is supported by European Investment Funds by FEDER/COMPETE/POCI-Operacional Competitiveness and Internacionalization Programme, under Project POCI-01-0145-FEDER-006958 and National Funds by FCT-Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2013. The author Iva Prgomet acknowledges the financial support provided by the FCT- Portuguese Foundation for Science and Technology (SFRH/BD/52539/2014), under the Doctoral Programme "Agricultural Production Chains-From Fork to Farm" (PD/00122/2012).

Chufa, also known as tigernut, is a typical crop in Valencia, Spain, where it is cultivated in ridges with furrow irrigation. This paper examines the effects of the planting strategy (PS) and irrigation system (IS) on yield and irrigation water use efficiency (IWUE) on the basis of the results from a two-year study. The authors analyzed three PS, ridges with a plant row (R) and flat raised beds containing two (B2) or three (B3) plant rows and compared two IS, furrow (FI) and drip irrigation (DI). Irrigation was based on the volumetric soil water content (VSWC), continuously monitored with capacitance sensors. Each irrigation event started when the VSWC in R dropped to 60 or 80% of the field capacity in FI or DI, respectively. Beds and ridges were irrigated simultaneously and for the same duration. There were differences among IS and PS, with DI and B2 obtaining the highest yield. On average, DI produced higher IWUE values than FI; the highest IWUE was obtained in R for DI, and the lowest IWUE was obtained in R for FI. Thus, modifications to the PS and the IS in chufa cultivation will increase IWUE and lead to major water savings.

[EN] The production of seed propagated artichoke is considered one possible alternative to the vegetative propagation of green and purple artichoke heads. One drawback of using seed propagated artichokes is their late entry into production. In this study different gibberellic acid (GA3) concentrations, sprayed over different cultivars of seed propagated artichoke, are analysed in order to know the influence on earliness, yield, quality and crop behaviour. The experiment was carried out at the Experimental Station of Foundation Ruralcaja in Paiporta (Valencia, Spain), using six seed propagated cultivars, three with green heads (‘Imperial Star’, ‘Symphony’ and ‘Madrigal’) and three with purple heads (‘Opal’, ‘Opera’ and ‘Concerto’). On 21 July 2010 the potted plants were transplanted into a sandy loam soil, in lines 1.70 apart and 0.825 m between plants. Plants were sprayed three times every two weeks with GA3 at concentrations 0, 30, 60 and 90 mg L-1, starting on the 10 September. A foliar fertiliser was added at 0.1% (v/v) GA3 solution. In both green and purple head artichoke cultivars it was observed that the earliest cultivars need a lower concentration of GA3 (between 30 and 60 ppm) to produce in autumn, while late cultivars need highest concentrations of GA3 (90 ppm). In general, the greatest final yield was achieved by the control and the highest concentrations of GA3 induced to a lowering final yield, especially in the earliest cultivars. This reduction was also observed in late cultivars (‘Concerto’ and ‘Madrigal’) with the highest concentration (90 ppm). The largest GA3 concentrations produced initially a greater growing and an erect aspect of plants. On the contrary, the highest plant height was noticed in plants sprayed with the lowest concentrations of GA3 and in control plants., Thanks to Conselleria de Agricultura Pesca y Alimentación for the financial assistance in this study, which is included in the developed research for Programa Hortofrutícola, an I+D+i project

Chufa (Cyperus esculentus L. var. sativus Boeck.) is an important vegetable crop in Valencia (Spain), where its tubers are used to produce a refreshing drink called ¿horchata¿. Water is relatively inexpensive, there are no data regarding the volumes of water used to grow chufa, and the irrigation water use efficiency (IWUE) has neither been determined. The aim of this research was to compare the productive responses of the chufa crop to two irrigation strategies (IS). The volumetric soil water content (VSWC) was monitored with capacitance sensors. Trends in VSWC were used to determine the in situ field capacity (FC), beginning each irrigation event when the VSWC reached either approximately 45% (H1) or 60% (H2) of the FC at a soil depth of 0.10 m. The experiments were conducted over three consecutive seasons. An area velocity flow module measured the water flow. The yields, the water volumes used, and the IWUE were calculated. Plants were periodically sampled and the harvest index and relative growth rate were determined. The yield was affected by the year and by the IS. The greatest yields were obtained with the H2 strategy (on average 2.18 kg m¿2 for H2 vs. 1.94 kg m¿2 for H1; p ≤ 0.01), and the average tuber weight (ATW) was affected (p ≤ 0.01) by the year and IS interaction. IWUE was affected by the year, and none of the considered factors affected the harvest index (p ≤ 0.05). It can be concluded that maintaining a higher VSWC would increase both yield and ATW without affecting IWUE., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain.

Chufa (Cyperus esculentus L. var. sativus Boeck.) is a traditional crop in the Mediterranean region of Spain, where it is only furrow irrigated. This article analyzes the irrigation performance for this crop, conducting field studies over three consecutive seasons in Valencia (Spain). Irrigation schedule was based on the volumetric soil water content, which was measured with capacitance sensors. Infiltrability was measured with blocked-furrow infiltrometers. An area velocity flow module measured the water flow, the cross-sectional geometry of furrows was determined using furrow profilometers, and times for advance and recession were recorded. WinSRFR software was used to analyze every irrigation event, determining the application efficiency (AE) and distribution uniformity of the minimum (DUmin), and to optimize the combination of furrow inflow (q) and cut-off time (Tco). Average values obtained for AE were 30.1%, 25.6%, and 26.7% in 2007, 2008, and 2009, respectively, and the corresponding DUmin values were 0.54, 0.61, and 0.67. Optimized results showed that it is possible to reach AE and DUmin values up to 87% and 0.86, respectively. However, understanding the q-Tco relationship that maximizes both AE and DUmin is more important than knowing the specific values. A function that related q and Tco was obtained for the typical plot dimensions, and this was validated in 2011. Therefore, this function can be used in most of the plots in the cultivation area., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain. The authors would like to thank Dr. E. Bautista for his help with the use of the Win SRFR 3.1 software.

[EN] Agricultural communities in the semiarid regions of the world are constantly being affected by water scarcity, increased regulations restricting water use, strong competition for irrigation water with the urban sector, and severe drought periods. Conversely, the consumer demand for high-quality and nutritious foods is increasing rapidly. A 2-year field study evaluated growth, yield, and bulb quality in response to precision planting density and deficit irrigation of onion ( Allium cepa L.) in southwest Texas. Seeds of short-day sweet onion cv. Texas Grano 1015Y were planted in the field on 11 Nov. 2007 and 30 Oct. 2008 at two planting densities (PDs), 397,000 (standard) and 484,000 (high) seeds/ha. Three irrigation rates using growth stage-specific crop co- efficients and subsurface drip were imposed after plants were fully established, 100%, 75%, and 50% crop evapotranspiration rates (ETc). Total rainfall plus irrigation received for each irrigation rate were 594, 501, and 413 mm in 2008 and 662, 574, and 486 mm in 2009. In both seasons, there were consistent trends in growth, yield, and quality parameters. Leaf fresh weight was unaffected by PD but was reduced by deficit irrigation at 50% ETc. Although increasing planting density reduced the average bulb size by 12%, it increased the number of marketable bulbs by 21% to 33% and marketable yield by 7% to 14%. In contrast, deficit irrigation showed a trend to reduce both the number of bulbs and bulb size with yield reductions of 8% to 13% at 75% ETc and 19% to 27% at 50% ETc. Neither planting density nor deficit irrigation rate had a significant effect on soluble solids content, pungency, or quercetin contents. These results suggest that growers of short-day onions in semiarid regions could adjust PDs to target high-value bulb sizes. Implementing water-conserving practices (deficit irrigation at 75% ETc rate) would result in a decrease of high-value bulb grades and modest losses in yield but not flavor or nutritional components.

[EN] The efficiency of fertilisation in agriculture is often low, and if one knows the nutrient uptake rate, efficiency can be improved by synchronizing nutrient supply with nutrient demand. Growth and the time-course of nutrient accumulation and its partitioning between the different organs of chufa (Cyperus esculentus L. var. sativus Boeck.), an under-exploited cultivated plant, were examined. The study was conducted in soilless, open-field conditions, at a planting density equivalent to 55,500 plants ha-1 in three consecutive seasons. Plants were sampled, fractionated into leaves, roots, and tubers, then dried and weighed. Their macronutrient contents were analysed fortnightly. On average, the yield was 5.0 kg fresh weight tuber m-2 . Growth of the whole plant until 90 d after planting obeys an exponential function of time; the relative growth rate (RGR) for this period was determined. The highest N and K concentrations were recorded in leaves, and the highest P, Ca and Mg concentrations were found in roots. The highest accumulations of N and P were found in tubers, and of K and Ca in leaves. Nitrogen had the highest nutrient accumulation (58.3 g m-2 ) as well as the highest specific uptake rate., This study was funded by the Consejo de Denominacion de Origen Chufa de Valencia, Spain. The authors thank the agricultural engineers, Juan Andres and Ramon Ballester, for assisting with the previous experiments, and Debra Westall for revising the manuscript.