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Green beans (Phaseolus vulgaris L.) is one of the most interesting vegetable crops for extra-seasonal cultivation, as it may achieve high prices on the market, making its cultivation more remunerative when done in greenhouse. However, indoor cultivation may be subjected to disadvantageous conditions in terms of light quantity, especially in autumn and winter, and this condition may be limited for green bean indoor cultivation. Light-emitting diode (LED) technology is gaining popularity, as it allows using specific spectra to increase light quantity and modulate the quality of the spectrum, while its cost is decreasing. In this study, we applied three light spectra (blue (450 nm), red (660 nm), and blue plus red light, during four hours before sun rise, with an intensity of 500 ?mol m s) supported by LED fixtures to enhance yield of green beans in a cold greenhouse. The LED treatments received also sunlight, and the control treatment was the sunlight without LED. Plants ('Maestrale') were transplanted on August 22 and harvested from November 4 to December 18, 2019. Colour (CIELab colour scale) of pods, SPAD of leaves and yield were determined. Based on our results, with the addition of supplemental blue light, the plants produced more, especially compared to sunlight (on average, 54.7 vs. 47.1 pods plant and 99.8 vs. 78.0 g plant). With blue light, the leaves showed SPAD values lower than red light but 5.4% higher than in sunlight, while the green colour (a*) of the pods was less intense with blue light (with or without red light) compared to red light and sunlight (-15.7 vs. -16.6).

Unidad de excelencia María de Maeztu CEX2019-000940-M BACKGROUND: Urban agriculture contributes to meet food production demand in cities. In a context of low water availability, it is important to consider alternatives that are able to maintain production. This study aimed to assess the use of substrates made from local materials and high water retention capacity as an alternative for urban agriculture in periods with water stress. Different substrates were used for 3 consecutive crop cycles of lettuce (Lactuca sativa L.) during the spring and summer periods of 2018 to observe these substrates performance during warmer periods of the year in an integrated rooftop greenhouse near Barcelona. The substrates used were coir commercial organic substrate, vegetable Compost from urban organic waste, Perlite (as control) commercial standard substrate, and a Mixture of the urban Compost and Perlite (1:1). Substrate crop performance was assessed under conventionally irrigation (0-5 cbar) and water restricted conditions (irrigation stop until the water tension inside the perlite bags reached -20 cbar). RESULTS: The results demonstrate that the Compost and Mix yields were similar to those obtained from Perlite (11.5% y 3.7% of more production in a restricted water condition average values). Compared to the Perlite, the organic substrates increased the crops resilience to water restriction, through biomass accumulation comparison, it took longer for Coir to lose water (1 and 2 test); however, when dryness began, it occurred very quickly. CONCLUSION: The vegetable Compost and the substrate Mixture presented tolerance to water restriction when water restriction reached -20 cbar.

Iron (Fe) biofortification is a strategy to increase the amount of iron in food crops. The goal of this work was to assess the possibility of maximizing the Fe content in cherry tomatoes grown in a soilless system. The cultivar Creativo was grown with three concentrations of Fe (as Fe-HBED) in the nutrient solution (0.022, 1, and 2 mmol L−1), and received further foliar applications of the element (as Fe-DTPA) at 0, 250, and 500 µmol L−1. The addition of 2 mmol Fe L−1 to the nutrient solution, together with foliar sprays at 500 µmol Fe L−1, induced the highest increase in fruit Fe concentration in clusters 1 and 2 (by 163% and 190%, respectively). The Fe added to the nutrient solution increased the fruit dry matter (up to +10.21%) but decreased the fruit’s fresh weight (up to −11.06%). The higher Fe concentrations provided to the crop synergistically increased the contents of other minerals (i.e., K, Mg, Na, and Zn), along with the fruit’s titratable acidity and soluble solids content, improving multiple functional and quality traits of the cherry tomatoes. These results show that Fe biofortification of cherry tomatoes can be effective to address Fe deficiency while obtaining high-quality products.

The aim of this study was to test Posidonia oceanica (L.) Delile seagrass residues (leaves and fibers) as growing media component to improve the nutritional quality of two different brassica microgreens (Mizuna and Rapini). We hypothesized that addition of posidonia residues in the substrate would result in higher concentration of certain mineral nutrients in the edible parts of plants. Substrates were obtained by mixing leaves and fibers, each material at the rate of 25, 50 and 75% (v/v), with a peat based commercial substrate, that was also used at 100% rate as a control treatment. Two experiments were carried out (Experiment 1: Mizuna microgreens production in growth chamber conditions; Experiment 2: Mizuna and Rapini microgreens production in greenhouse conditions). Plant growth measurements and chemical analysis on edible parts (mineral tissue composition and main bioactive compounds - polyphenol, chlorophylls and carotenoids contents) were performed in order to evaluate the effects of the different substrates on growth and nutritional composition of brassica microgreens. In order to evaluate the consumer safety, daily intake, percentage of recommended daily allowance for I (RDA-I) and hazard quotient (HQ) for I intake through consumption of 50 and 100 g portions of Rapini microgreens were calculated. Posidonia in the growing media mixtures increased I and B content in edible parts of microgreens. The calculated HQ underlines the safety of these products. Results confirm the possibility to improve nutritional profile of brassica microgreens by using this natural material as a growing media component, resulting in a sustainable approach.

Unidad de excelencia María de Maeztu MdM-2015-0552 Urban agriculture is growing in cities and is rising to the roofs of buildings. The potential food contamination is a key issue to be resolved to guarantee the health of consumers, and it affects both urban agriculture promoters and consumers. Crop contamination from the soil can be overcome by adopting a soilless cultivation system that, with good management practices, can also avoid contamination from the fertirrigation system and pest treatments. It has recently increased the number of soilless cultivation systems in cities due to the good features it offers. This study focuses on the potential contamination of heavy metals in hydroponic lettuce crops due to atmospheric pollution in high-traffic areas. The contents of heavy metal in the air and the lettuce leaves were measured at 4 sites: a periurban-integrated rooftop greenhouse, a periurban rooftop, an urban courtyard and an urban rooftop. High-volume sensors were used to assess air contamination. Lettuce leaves were analysed to evaluate the heavy metal concentrations. The results show that the heavy metal concentration in lettuce leaves is also below the EU-legislated limit in all studied cases. Specifically, the concentrations below the detectable analytic values were

Volatile compounds are essential for food organoleptic characteristics and of great utility for the food industry as potential markers for authenticity purposes (e.g., variety, geographical origin, adulteration). The aim of this study was to determine the characteristic volatile compounds of strawberry samples grown in a soilless system by using headspace solid phase micro-extraction coupled with gas chromatography and to investigate the influence of cultivar (Festival, Candonga, Camarosa) on this volatile profile. We observed that Festival and, to a lesser extent, Candonga varieties were characterized by the richest aroma-related profiles, including higher levels of esters, furanones and terpenes. In particular, methyl butyrate, hexyl hexanoate, linalool, geraniol and furaneol were the most abundant aromatic compounds detected in the three varieties of strawberries. Complementarily, the application of pattern recognition chemometric approaches, including principal component analysis and linear discriminant analysis, demonstrated that concentrations of specific volatiles can be employed as chemical descriptors to discriminate between strawberry cultivars. Accordingly, geraniol and hexyl hexanoate were found to be the most significant volatiles for the discrimination of strawberry varieties.

Molybdenum (Mo) is an essential trace element for plant growth, development, and production. However, there is little known about the function and effects of molybdenum in tomato plants. The present study assessed the influences of different Mo concentrations on four tomato F1 hybrids (“Bybal” F1, “Tyty” F1, “Paride” F1, and “Ornela” F1) grown using a soilless system with different Mo levels [0.0, 0.5 (standard NS), 2.0, and 4.0 μmol L−1, respectively]. The crop yield, plant vigor, fruit skin color, TA, fruit water content as well as the accumulation of SSC, and some antioxidant compounds such as lycopene, polyphenols and ascorbic acid were evaluated. The minerals concentration, including nitrogen (N), Mo, iron (Fe), and copper (Cu), were measured in tomato fruits. Results revealed that tomato plants grown with 2.0 μmol Mo L−1 compared to plants grown with 0.5 μmol Mo L−1 incurred a significant increase of total yield by 21.7%, marketable yield by 9.1%, aboveground biomass by 16.7%, plant height at 50 DAT by 6.5%, polyphenol content by 3.5%, ascorbic acid by 1.0%, SSC by 3.5%, N fruit content by 24.8%, Mo fruit content by 20.0%, and Fe fruit content by 60.5%. However, the Mo concentration did not significantly influence the average fruit weight, b∗ fruit skin color coordinate and TA. Furthermore, tomato fruits from plants grown with 2.0 μmol Mo L−1 showed a lower Cu fruit content (16.1%) than fruits from plants grown with 0.5 μmol Mo L−1 (standard NS). Consequently, our study highlights the different behavior of the tomato genotypes tested when subjected to different levels of Mo concentration in the nutrient solution. Nevertheless, taking all in consideration our results clearly suggest that a Mo fertilization of 2.0 μmol Mo L−1 effectively enhance crop performance and overall fruit quality of tomato.

L'agricultura urbana (AU), especialment en les cobertes (AR), és una pràctica cada vegada més implementada per a complementar la creixent demanda de producció local d'aliments a les ciutats. Diversos treballs de recerca han demostrat la viabilitat tècnica d'aquest tipus d’instal·lacions d'agricultura i han quantificat els seus impactes ambientals. No obstant això, encara no s'ha dut a terme una recerca profunda sobre la qualitat del sistema productiu en cobertes que afecta tant, a l'entorn, al propi sistema on es conrea, com al producte final obtingut, en aquest cas, l'aliment. En general, la contaminació per metalls pesats és un dels temes principals en el debat sobre la seguretat alimentària i en el cas de la AU hi ha major preocupació pel fet que els cultius solen estar pròxims a zones d'alta densitat de trànsit. Una altra preocupació específica dels cultius protegits és la qualitat aerobiológica dins dels hivernacles. El nivell de concentració de pol·len i espores de fongs pot afectar els treballadors i es desconeix quina és la situació dels hivernacles urbans (RTG) i el potencial impacte en cas de realitzar una recirculació. L'alt consum d'aigua en la UA mediterrània, on l'aigua és un recurs escàs i que augmentarà en el futur a causa del canvi climàtic també és un aspecte clau a resoldre. A més, existeix una demanda per a promoure la AU en el context de les ciutats en el marc de l’economia circular aprofitant residus verds pròxims al lloc del cultiu, i reduint els seus impactes ambientals. Els aspectes esmentats anteriorment porten a analitzar quina és la percepció i acceptació d'aquest tipus d'agricultura i els aliments produïts entre els consumidors. La present tesi doctoral aborda aquest àmbit d'estudi intentant donar resposta a les següents preguntes: - Quina és la potencial contaminació de metalls pesants en els cultius sense sòl de l’agricultura urbana en coberta a l’aire lliure o en hivernacles deguda a la contaminació atmosfèrica de les ciutats? - Les condicions biològiques de l'aire en els hivernacles en coberta són adequades per a proporcionar entorns de treball segurs? I en el cas dels hivernacles integrats, es pot recircular el seu aire residual amb finalitats aprofitament energètic, al mateix temps que es garanteix un entorn segur de qualitat biològica per als usuaris de l'edifici? - Estem utilitzant substrats ambientalment adequats per a l'agricultura urbana sense sol capaços de mitigar els efectes del canvi climàtic fent-los resilients a la sequera? - Quina és la percepció del consumidor de l'agricultura en coberta i els productes conreats en elles? Aquesta tesi contribueix a un major enteniment dels principals factors que influeixen en la qualitat dels productes de RA i els sistemes de cultiu alhora que aporta noves estratègies per a millorar qualitat. Els resultats obtinguts en els diferents escenaris d'estudi demostren que en el context urbà es poden produir aliments d'alta qualitat, amb elevats rendiments productius alhora que es promouen estratègies d'economia circular com l'ús de residus vegetals urbans com a substrat. La futura recerca relacionada amb aquesta àrea de coneixement podria centrar-se en els següents temes: la qualitat dels productes i els sistemes de producció de la AU podrien centrar-se en els següents temes: • avaluar la contaminació d'altres contaminants atmosfèrics • estudiar la contaminació per metalls pesats en cultius de cicle llarg • estudiar la dinàmica de partícules al·lergògenes durant l'hivern, època amb menor taxa de renovació d'aire en un RTG • aprofundir en la cerca i optimització de substrats orgànics locals en la RA • Aprofundir en la percepció de la qualitat a través d'estudis organolèptics amb panells de tast així com utilitzar altres tècniques de caracterització d'aliments com l’espectroscòpia La agricultura urbana (AU), especialmente en las cubiertas (AR), es una práctica cada vez más implementada para complementar la creciente demanda de producción local de alimentos en las ciudades. Diversos trabajos de investigación han demostrado la viabilidad técnica de este tipo de agricultura y han cuantificado sus impactos ambientales. Sin embargo, aún no se ha llevado a cabo una investigación profunda sobre la calidad del sistema productivo en cubiertas que afecta tanto, al entorno, al propio sistema en donde se cultiva, como al producto final obtenido, en este caso, el alimento. En general, la contaminación por metales pesados ​​es uno de los temas principales en el debate sobre la seguridad alimentaria y en el caso de la AU hay mayor preocupación debido a que los cultivos suelen estar próximos a zonas de alta densidad de tráfico. Otra preocupación específica de los cultivos protegidos es la calidad aerobiológica dentro de los invernaderos. El nivel de concentración de polen y esporas de hongos puede afectar los trabajadores y se desconoce cuál es la situación de los invernaderos urbanos (RTG) y el potencial impacto en caso de realizar una recirculación. El alto consumo de agua en la UA mediterránea, donde el agua es un recurso escaso y que aumentará en el futuro a causa del cambio climático es un aspecto clave a resolver. Además, existe una demanda para promover la AU en el marco de la economía circular en las ciudades aprovechando residuos verdes cercanos al lugar del cultivo, y reduciendo sus impactos ambientales. Los aspectos mencionados anteriormente llevan a analizar cuál es la percepción y aceptación de este tipo de agricultura y los alimentos producidos entre los consumidores. La presente tesis doctoral aborda este ámbito de estudio intentando dar respuesta a las siguientes preguntas: - ¿Cuál es la potencial contaminación de metales pesados en los cultivos sin suelo de la agricultura urbana en cubierta al aire libre o en invernaderos debida a la contaminación atmosférica de las ciudades? - ¿Las condiciones biológicas del aire en los invernaderos en cubierta son adecuadas para proporcionar entornos de trabajo seguros? Y en el caso de los invernaderos integrados, ¿se puede recircular su aire residual con finalidades aprovechamiento energético y al mismo tiempo se garantiza un entorno seguro de calidad biológica para los usuarios del edificio? - ¿Estamos utilizando sustratos ambientalmente adecuados para la agricultura urbana sin suelo y capaces de mitigar los efectos del cambio climático haciéndolos resilientes a la sequía? - ¿Cuál es la percepción del consumidor de la agricultura en cubierta y los productos cultivados en ellas? Esta tesis contribuye a un mayor entendimiento de los principales factores que influyen en la calidad de los productos de RA y los sistemas de cultivo a la vez que aporta nuevas estrategias para mejorar calidad. Los resultados obtenidos en los distintos escenarios de estudio demuestran que en el contexto urbano se pueden producir alimentos de alta calidad, con elevados rendimientos productivos a la vez que se promueven estrategias de economía circular como el uso de residuos vegetales urbanos como sustrato. La futura investigación relacionada con esta área de conocimiento podría centrarse en los siguientes temas: • evaluar la contaminación de otros contaminantes atmosféricos • estudiar la contaminación por metales pesados en cultivos de ciclo largo • estudiar la dinámica de partículas alergénicas durante el invierno, época con menor tasa de renovación de aire en un RTG • profundizar en la búsqueda y optimización de sustratos orgánicos locales en la RA • Profundizar en la percepción de la calidad a través de estudios organolépticos con paneles de cata así como utilizar otras técnicas de caracterización de alimentos como la espectroscopia Urban agriculture (UA), particularly rooftop urban agriculture (RA), has increased in the last few years to satisfy the growing demand for local food production in cities. Previous research has demonstrated the technical viability and quantified the environmental impacts of producing food on rooftops, both in and outside greenhouses. However, no in-depth research has been carried out yet on the key aspect of food quality, which cuts right across the environment, the system and the final product, in this case the food. In general, heavy metal pollution is one of the most pressing concerns in the deliberation about food security and food safety in Europe. Additionally, in the case of UA, crops are often very close to roads with heavy traffic and with a high atmospheric pollution risk. Another relevant concern about air quality specific to protected crops is the biological air quality inside greenhouses. The concentration levels of pollen and fungus spores suspended in the air can affect people who regularly work in the greenhouse and it is not known how this plays in an urban context. High water consumption of gardens in Mediterranean cities, where water is a scarce resource, is also a key factor to assess. At the same time, there is a demand to promote UA in the context of circular cities, using green materials near the place of consumption, which helps reduce the environmental impacts of food production. For these reasons, it was also considered essential to study customers’ perception and acceptance of this type of agriculture and the food it produces. This doctoral thesis aims to fill these gaps by addressing the following research questions: - Does atmospheric heavy metal pollution in cities contaminate soilless crops from RA and RTGs? - Are the biological air conditions in RTGs adequate to provide safe working environments? And in the case of i-RTGS, can its air be recirculated while ensuring safe environment for building users? - Are we using adequate substrates for urban agriculture to mitigate the effects of climate change and increase resilience to drought? - What is the consumer’s perception of RA and products grown in these systems? This dissertation contributes to understanding the main factors influencing the quality of food and RA cultivation systems and provides new strategies to increase their quality. The results from the different points analyzed demonstrate that, in an urban context, it is possible to produce high quality food products from high crop yields while adopting circular economy strategies, such as the use of biowaste as a substrate. Future research on the fields assessed might focus on the following areas: • Evaluating contamination through additional atmospheric pollutants • Determining the heavy metal content in longtime leafy crops • Studying the dynamics of allergenic particles in winter, the season with the lowest ventilation levels inside an RTG • Exploring and optimizing organic substrates from local RA • Further assessing the perception of quality through organoleptic studies with trained panels and with other techniques of food characterization, such as spectroscopy

Basil (Ocimum basilicum L.) is one of the most common aromatic herbs cultivated all over the world. It is widely used for aromatic and culinary purposes. Two greenhouse experiments were carried out to determine the effects of increasing the level of salinity in the nutrient solution (1 or 40 mM NaCl) during two consecutive growing seasons (summer and autumn) on growth, yield and leaf-quality traits of green sweet basil 'Mammolo' grown in an open-loop system. Increased salinity in the nutrient solution from 1 to 40 mM decreased fresh yield and final leaf area, with a more detrimental effect during the warm season. The percentage reductions in yield and leaf area in comparison with the non-saline control were respectively 30 and 42% in the summer cropping season and 20 and 16% in the autumn season. Increasing the NaCl concentration in the nutrient solution from 1 to 40 mM increased the hydrophilic antioxidant activity (HAA) and total phenolics (TP) by 87 and 17%, respectively, and reduced the nitrate content by 84%. When averaged over salinity level, TP increased and the nitrate content decreased in plants grown in summer compared with the autumn growing season.

Compost has been recently suggested as an alternative to peat for the preparation of growing substrates in soilless cultivation systems. However, some physico-chemical properties of compost may reduce plant performance and endanger the quality of productions, in particular for possible heavy metal accumulation in edible parts. This study aims at evaluating the suitability of a municipal solid waste compost (MSWC) and a sewage sludge compost (SSC) as components of growing media for the soilless cultivation of lettuce (Lactuca sativa L.). Heavy metal content of SSC complied with legislation limits but, in MSWC, it exceeded (Cu, Pb) or was very close (Cd, Zn) to safe limits. A greenhouse experiment was carried out by cultivating four lettuce cultivars ("Maximus," "Murai," "Patagonia," and "Aleppo") in pots containing a mixture of MSWC and perlite (MSWC + P), SSC and perlite (SSC + P), or peat and perlite (peat + P), the latter used as control. Plant biometric parameters measured after 72 days of growth revealed that the yield of plants cultivated on SSC + P was similar to control plants, independently of the cultivar. Conversely, MSWC + P suppressed in general the biomass production, especially for Murai and Patagonia cultivars. Compared to peat + P, both compost-based substrates reduced the leaf accumulation of heavy metals, with a major effect in Maximus plants. The levels of Cd and Pb in the edible part were always below the safe limits imposed by European regulation. Therefore, risks of heavy metal intake in food chain associated with the replacement of peat with compost in the growing media are negligible, even when a compost with a significant amount of heavy metals is used. Besides compost quality monitoring, also an appropriate varietal choice is crucial to obtain good yields and safe products.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The potato plant is highly demanding regarding the presence of phosphorus (P) readily available in soil solution. To achieve high yields of tubers, large applications of phosphate fertilizers are made, which consequently reduce the sustainability of the potato chain and cause possible environmental contamination. Therefore, it is necessary to improve the management of fertilizer use and develop potato clones that have high yield and quality, even in limiting conditions of P. In order to identify efficient clones in P acquisition and use, this study aimed to characterize the physiological aspects of potato clones under different levels of P availability and production systems available. In the first experiment, the Asterix, Atlantic, SMIC 148-A and SMINIA 793101-3 clones from micropropagated plants were grown in soilless system under low and high P level (2.32 and 23.2 mg P L-1) during the spring and autumn seasons of Rio Grande do Sul state. In the P utilization efficiency, we found that the potato clones differ between the spring and autumn season of Rio Grande in soilless culture system with the use of sand as substrate. Furthermore, we also compared the P efficiency of these clones between soilless system and field cultivation under low and high P level (70 and 560 kg P2O5 ha-1) in the spring crop. We observed that each clone responds differently to cultivation systems used as nutritional efficiency to P, and the closed cultivation soilless system with use of sand as substrate overestimates the responses of potato clones in relation to P availability. Nevertheless, we sought to differentiate micropropagated potato plants of plants produced from minitubers as nutritional efficiency to P in closed cultivation soilless system with use of sand as substrate under high and low P level again. The data suggest that the propagative origin of the potato plants interferes, in the biomass ratio between root and shoot, and in the harvest index and P utilization efficiency for all clones. The Asterix, Atlantic and SMIC 148-A clones suffer interference of the type of propagation material in use efficiency and P response, while the SMINIA 793101-3 clone is P efficient in the use of nonresponsive in fresh mass production and tubers total dry mass, regardless of propagativa type of the plants. Furthermore, the clones were also evaluated with plants from tubers when grown in pots with soil as substrate in low and high P level (0.025 and 0.11g kg-1) in a greenhouse, we observed based on the total dry mass, the SMIC 148-A and SMINIA 793101- 3 clones are efficient in the use of P, while Atlantic and SMINIA 793101-3 are responsive to the increase of P. A planta de batata é altamente exigente quanto à presença de fósforo (P) prontamente disponível na solução do solo. Para atingir altas produções de tubérculos são feitas grandes aplicações de adubos fosfatados, reduzindo assim, a sustentabilidade da cadeia produtiva da batata, além de causar uma possível contaminação ambiental. Portanto, é preciso melhorar a gestão do uso dos fertilizantes e desenvolver clones de batata que tenham alto rendimento e qualidade, mesmo em condições limitantes de P. Este trabalho teve por objetivo caracterizar aspectos fisiológicos de clones de batata submetidos a diferentes níveis de disponibilidade de P e sistemas de produção disponíveis para identificar clones eficientes na aquisição e no uso do P. No primeiro experimento os clones Asterix, Atlantic, SMIC 148-A e SMINIA 793101-3 provenientes de plantas micropropagadas foram cultivados em sistema fechado fora do solo sob baixo e alto nível de P (2,32 e 23,2 mg P L-1) durante a primavera e o outono do Rio Grande do Sul. Verificou-se que os clones de batata diferem quanto à eficiência de utilização do P entre os cultivos de primavera e outono do Rio Grande do Sul em sistema de cultivo sem solo com o uso de areia como substrato. Em outro momento, avaliou-se a eficiência ao P desses clones no cultivo fora do solo e à campo sob baixo e alto nível de P (70 e 560 kg P2O5 ha-1) na safra de primavera. Observou-se que cada clone responde de uma maneira diferente aos sistemas de cultivo utilizados quanto a eficiência nutricional ao P, sendo que o sistema fechado de cultivo fora do solo com o uso de areia como substrato superestima as respostas dos clones de batata em relação à disponibilidade de P. Ainda, buscou-se diferenciar plantas de batata micropropagadas de plantas produzidas a partir de minitubérculos quanto a eficiência nutricional ao P em sistema de cultivo fechado fora do solo com o uso de areia como substrato novamente sob alto e baixo nível de P. Os dados sugerem que a origem propagativa de plantas de batata interfere, tanto na relação de biomassa entre raiz e parte aérea, quanto no índice de colheita e na eficiência de utilização do P para todos os clones. Os clones Asterix, Atlantic e SMIC 148-A sofrem interferência do tipo do material propagativo na eficiência de uso e resposta ao P, enquanto o clone SMINIA 793101-3 é eficiente no uso e não responsivo ao P na produção de massa fresca de tubérculos e massa seca total, independente da origem propagativa das plantas. Os clones de batata também foram avaliados a partir de tubérculos em vasos tendo solo como substrato com baixo e alto nível de P (0,025 e 0,11g kg-1) em casa de vegetação, sendo observado com base na produção de massa seca total, que os clones SMIC 148-A e SMINIA 793101-3 são eficientes no uso de P, enquanto que Atlantic e SMINIA 793101-3 são responsivos ao incremento de P.

La relación directa entre la calidad de la fresa y su contenido en metabolitos determina la necesidad de estudiar su composición química utilizando metodología analítica que permita la identificación y cuantificación exacta y reproducible del mayor número posible de compuestos relacionados con sus cualidades organolépticas, nutricionales y nutracéuticas. La importancia económica de la fresa en la provincia de Huelva y la competitividad existente dentro del sector hace necesario el desarrollo de nuevos métodos de producción, que basados en la manipulación de los recursos naturales (luz, agua y nutrientes), mejoren la resistencia de la planta, la productividad, la calidad y propiedades nutracéuticas. En este sentido, los cultivos sin suelo parecen una alternativa prometedora para incrementar la sostenibilidad y competitividad del cultivo de la fresa. Asimismo, la introducción de variedades precoces, que permiten la producción fuera de temporada, es otro de los retos que se plantea el sector. La calidad de fruta, incluyendo las características nutricionales y nutracéuticas, está influenciada por la variedad, las prácticas de cultivo, el clima y la región de producción así como por el tiempo de muestreo, el grado de madurez y los estresantes bióticos y abióticos. Por lo tanto, muchas variables pueden afectar considerablemente los valores dietéticos de la fruta y numerosos estudios se han centrado en explicar las relaciones entre la calidad de la fruta y estos factores. Es por ello que en este trabajo de Tesis Doctoral, se han estudiado y analizado varias variedades de fresa cultivadas en sistema de cultivo sin suelo en diferentes condiciones agronómicas, y en sistema convencional con el fin de evaluar el efecto de estas condiciones agronómicas y ambientales sobre la calidad de fresa. Los resultados de este trabajo se han desglosado en tres capítulos. En el primer de ellos, se proporciona un conocimiento más profundo de la composición orgánica e inorgánica de la fresa para evaluar el efecto de los métodos de producción sobre la calidad de la misma. Para ello, se utilizaron dos grupos de muestras: el grupo I formado por seis variedades de fresas, Camarosa, Candonga, Chiflón, BG 269, Tamar y Diamante cultivadas en un sistema sin suelo usando fibra de coco como sustrato, y el grupo II integrado por cinco variedades, Camarosa, Candonga, Medina, Marina y Ventana cultivadas en sistema convencional. Con el fin de evaluar la calidad de la fresa se determinaron varios parámetros químicos (sólidos solubles, azúcares, ácidos orgánicos y elementos minerales) en distintas variedades de fresa. Además, se investigaron las diferencias entre las fresas cultivadas en el sistema sin suelo frente al sistema de cultivo convencional aplicando técnicas estadísticas multivariantes. Los análisis se llevaron a cabo mediante cromatografía líquida (HPLC-DAD-RID) para la determinación de los azúcares y los ácidos orgánicos, y espectroscopia de emisión óptica de plasma acoplado inductivamente (ICP-OES) para la determinación del contenido mineral. Se observaron diferencias significativas entre las variedades basadas en la composición mineral y la concentración de glucosa y fructosa en ambos sistemas de cultivo. Sin embargo, no se detectaron diferencias significativas en la acidez. Tamar y Camarosa fueron las variedades más dulces entre todas las variedades cultivadas en el sistema sin suelo y el sistema convencional, respectivamente. Ambas variedades también presentaron la mayor proporción azúcares totales en relación al contenido en ácidos totales. Cuando se compararon ambos sistemas de cultivo también se observaron diferencias significativas en el contenido de minerales, azúcares y parámetros relacionados. En el segundo capítulo se evalúa la influencia de los factores ambientales, el tiempo de muestreo y el genotipo sobre la calidad nutricional y nutracéutica de la fresa, en base a los cambios en la concentración de metabolitos primarios (azúcares y ácidos orgánicos) y secundarios (compuestos fenólicos) y su bioactividad (actividad antioxidante). El estudio de los metabolitos se realizó en tres variedades de fresa cultivadas en sistema de cultivo sin suelo bajo diferentes condiciones agronómicas (detalladas en la parte experimental del capítulo II). Las tres variedades fueron elegidas en base a su sensibilidad a las condiciones ambientales: Palomar (muy sensible), Festival (sensible) y Camarosa (resistente). A lo largo de la campaña se realizaron tres muestreos: diciembre (producción extra temprana), enero y marzo (producción temprana). Los análisis se llevaron a cabo mediante cromatografía líquida (HPLC-DAD) y espectrofotometría uv-vis. Los resultados obtenidos mostraron que la variedad Festival fue el genotipo con mayor contenido de azúcares y mayor valor para la proporción azúcares totales / ácidos totales, mientras que la variedad Camarosa fue más rica en antocianos. Con respecto al tiempo de muestreo, se observaron que la fresa cosechada en enero y marzo tenía mayor calidad. La fresa cosechada en enero fue más rica en compuestos fenólicos mientras que la fresa cosechada en marzo fue más rica en compuestos relacionados con el sabor (azúcares y ácidos orgánicos). En el tercer capítulo se ha utilizado una estrategia metabolómica no dirigida (untargeted metabolomic) para caracterizar los metabolitos primarios en diferentes variedades de fresa y estudiar también sus alteraciones en respuesta a diferentes condiciones de cultivo y al estrés ambiental. Se analizaron tres variedades de fresa con diferente sensibilidad a los factores ambientales (Camarosa, Festival y Palomar) cultivadas en sistemas sin suelo, usando varias condiciones agronómicas: tres niveles de conductividad eléctrica (EC = 1, 2, and 3 dS/m), dos tipo de cobertura (tapada ó destapada) y tres tipos de sustratos (fibra de coco, perlita y lana de roca). Los metabolitos primarios fueron perfilados por cromatografía de gases acoplada con espectrometría de masas (GC- MS). Los resultados obtenidos mostraron la existencia de una alteración significativa en los metabolitos primarios en las tres variedades de fresa estudiadas, incluyendo azúcares (fructosa, glucosa), ácidos orgánicos (ácido málico, ácido cítrico) y aminoácidos (alanina, treonina, ácido aspártico), entre otros., The direct relationship between the quality of strawberry and its metabolites content determines the need to study its chemical composition using analytical methodology that allows accurate identification and quantification and reproducible of the largest number of compounds related to organoleptic, nutritional and nutraceutical properties. The economic importance of strawberries in Huelva and the competitiveness in the sector makes necessary the development of new production methods based on manipulating natural resources (light, water and nutrients) for improving plant resistance, productivity, quality and nutraceuticals properties. In this sense, soilless culture seems a promising alternative to increase sustainability and competitiveness of strawberry cultivation. Also, the introduction of early varieties that enable off-season production is another challenge posed by the sector. Fruit quality, including nutritional and nutraceutical properties, is influenced by the variety, cultural practices, climate and the region of production as well as the sampling time, degree of maturity and biotic and abiotic stressors. Therefore, many variables can affect significantly the dietetic values of fruit. Numerous studies have explained the relationship between fruit quality and these factors. For these reasons in this doctoral thesis it has been studied and analyzed several varieties of strawberries grown in soilless system in different agronomic conditions, and conventional system in order to evaluate the effect of these agricultural and environmental conditions on the quality of strawberry. The results of this memory have been structured in three chapters. The first one provides a more thorough knowledge of organic and inorganic composition of strawberries for assessing the effect of production methods on fruit quality. For this proposal, two groups of samples were used: The samples representing group I consisted of six varieties, i.e.Camarosa, Candonga, Chiflón, BG 269, Tamar and Diamante cultivated in a soilless system using coconut fiber as substrate. Fruit of five varieties cultivated using conventional practices, i.e. Camarosa, Candonga, Medina, Marina and Ventana, represented group II. In order to evaluate the quality of the strawberry some chemical parameters (soluble solids, sugars, organic acids and mineral elements) were determined in strawberries of several cultivars. In addition, differences between strawberries cultivated in soilless systems versus the conventional crop system were also investigated applying multivariate statistical techniques. The analyses were carried out using liquid chromatography (HPLC-DAD-RID) for determination of sugars and organic acids, and mineral contents were determined by inductively coupled plasma optical emission spectrometry (ICP- OES). Differences among cultivars were observed based on the mineral composition and glucose and fructose concentrations in both cultivation systems. However, no significant differences between cultivars were detected in sourness. Tamar and Camarosa were the sweetest cultivars among those grown in soilless and soil system, respectively. Both varieties also had the highest total sugars/total acids ratio. The comparison between strawberries cultivated in soil and soilless systems also revealed significant differences in the mineral composition, content of sugars and related parameters. In the second chapter the influence of environmental factors, seasonal and genetic factors on nutritional and nutraceutical quality of strawberry fruits are evaluated. Also it will allow to correlate them with changes in concentration of primary (sugars and organic acids) and secondary (phenolic compounds) metabolites and their bioactivity (antioxidant activity). The study of metabolites was performed in three strawberry varieties grown in soilless system under different agronomic conditions. The study of metabolites was performed in three strawberry varieties grown in soilless system under different agronomic conditions (detailed in experimental part of chapter II). The three varieties were chosen basing on their sensitivity to environmental conditions: Palomar (very sensitive), Festival (sensitive), and Camarosa (resistant). Throughout the campaign, three samplings were performed: December (extra-early production), January (early production), and March (early production). The analyses were carried out using liquid chromatography (HPLC-DAD) and UV-vis spectrophotometry. The results showed that variety Festival was the sweetest genotype and also had the highest total sugars/total acids ratio, whereas Camarosa was richest in anthocyanins. Considering the harvest time, it has been observed that the strawberry harvested in January and March (early production) had higher quality. Fruits harvested in January were richer in phenolic compounds whereas fruits harvested in March were richer in taste-related compounds (sugars and organic acids). In the third chapter, an untargeted metabolomic strategy was used to characterize the primary metabolome of different strawberry cultivars and to study metabolite alterations in response to different crop conditions and environmental stress. For this purpose, it were analyzed three varieties of strawberries with different sensitivity to environmental factors (Camarosa, Festival and Palomar) grown in soilless systems, and using various agronomic conditions: three levels of electrical conductivity (EC = 1, 2, and 3 dS/m), two different types of coverage (covered or uncovered) and Three types of substrates (coconut fiber, perlite and rock wool). Primary metabolites were profiled by gas chromatography mass spectrometry (GC-MS). The results showed significant alterations in primary metabolites between the three strawberry cultivars studied in this work, including sugars (fructose, glucose), organic acids (malic acid, citric acid) and amino acids (alanine, threonine, aspartic acid), among others.

This report contains a description of the activities carried out by CNR-ISPA (P4) in the framework of WP6 - Specialized research actions, Deliverable 6.4.3 and 6.4.5 - Experiments regarding sensors evaluation for greenhouses - Research report regarding the use of sensors for irrigation management. The activities focused on testing sensors for growing substrate parameters measurement (moisture and electrical conductivity), and sensor-based irrigation management strategies in greenhouse, with the aim to provide tools for irrigation decision and plant water requirements study. We implemented both laboratory and on-field activities, focusing on important greenhouse vegetable crops (namely tomato and lettuce) in Mediterranean environment. We also developed a pre-commercial prototype for the automatic sensor-based irrigation in greenhouse. Beside an introductive examination of the state of the art and of the concepts at the base of the carried out activities, a description of the experiments and of the results is included in this report. We outline that the full dataset from the experiments is at the moment under use or consideration for publication in scientific international journals, with the aim to present the outcomes of the IRMA project to the wide scientific community. Therefore, in order to be compliant with the universal requirement for scientific publication (the material should not have been previously published elsewhere, except in a preliminary form) we will not include in this report the full set of data; however, we will give anyway an exhaustive overview of the findings of the project activities.

Quality, microbiological and enzymatic characteristics of fresh-cut lettuce (Lactuca sativa var. longifolia, ‘Duende’), grown in floating system with three electrical conductivities of nutrient solutions (2.8, 3.8 and 4.8 mS cm−1), were investigated in order to evaluate the effect of salinity on product shelf-life during cold storage (9 d at 4 °C). Pre-harvest salinity of 3.8 and 4.8 mS cm−1 improved the properties of fresh-cut lettuce, since CO2 production was reduced with a subsequent control of the decay process. Fresh-cut processing caused an activation of polyphenol oxidase and peroxidase; in all cases the product obtained by salinity treatments was less subject to oxidase activity and browning phenomena during storage. Increased salinity reduced the number of mesophilic bacteria and of moulds and yeasts, assessed by plate counts on different culture media; in contrast, Enterobacteriaceae levels were unaffected by pre-harvest treatments. The research demonstrated that an increase in nutrient solution electrical conductivity, through the use of floating system, affects fresh-cut lettuce characteristics, improving shelf-life of the product.

The objectives of this research were to select new strawberry clones for the estate of Rio Grande do Sul, Brazil, and to develop methods of multiplication to obtain disease-free transplants with high physiological quality. Five advanced strawberry clones from the Breeding Program and two controls were evaluated in an annual hill system in low tunnels from April to December, 2006. A closed soilless system was developed, based on a growing bed with substrate over a cement tile. A nutrient solution was delivered from a reservoir to the upper end of the tile and drained off back by gravity. An inert substrate (sand) and an organic substrate (Plantmax®) and two advanced strawberry clones were tested. In another experiment fruit yield of plug transplants of different sizes was compared to that of bare-root transplants. Plug transplants were produced rooting runner tips in plastic trays with different volumes of organic substrate. Bare-root transplants were produced in the closed soilless growing system described above. Clones LBD 15.1, LBH 27.2, LBD 35.2 and LBG 121.4 were identified as having potential to be used in the estate of RS. These clones combine earliness, high yield and fruit quality, high content of bioactive compounds and resistance to diseases. A high number of healthy bare-root and runner tips with high quality were obtained with both substrates and both clones. A higher early fruit yield during fall and winter was obtained with plug transplants. Both plug and bare-root transplants reached a high total yield. It was concluded that selected strawberry clones of this research can be recommended to substitute commercial cultivars now planted in the RS or used in combination with them and that disease-free bare-root transplants and runner tips for plug transplants, both with high physiological quality can be produced in the closed soilless system, providing a sustainable alternative for nurseries. Os objetivos deste trabalho foram selecionar novos clones de morangueiro para o RS e desenvolver um sistema de multiplicação para a obtenção de mudas com alta qualidade fisiológica e sanitária. Foram avaliados cinco clones avançados do Programa de Melhoramento e duas testemunhas, em túneis baixos, durante os meses de abril e dezembro de 2006. Para a multiplicação foi utilizado um sistema fechado sem solo, baseado em um leito de cultivo com substrato sobre telhas de fibrocimento. A circulação da solução nutritiva foi feita a partir de um reservatório até a extremidade mais alta da telha, drenando por gravidade. Como substrato, testou-se a areia na categoria inerte e o Plantmax® na categoria orgânica, com dois clones. Em outro experimento foi comparada a produtividade de mudas com torrão de diferentes tamanhos e com raízes nuas. As mudas com torrão foram produzidas a partir de pontas de estolão enraizadas em bandejas com diferentes volumes de substrato orgânico. As mudas com raízes nuas foram provenientes do sistema fechado sem solo. Foram identificados os clones LBD 15.1, LBH 27.2, LBD 35.2 e LBG 121.4 com potencial para serem cultivados no RS. Esses clones combinam alta produtividade precoce e total, qualidade de fruta, conteúdo de componentes bioativos na fruta e resistência às doenças. Um alto número de mudas e pontas de estolão sadias e de alta qualidade foi obtido no sistema fechado sem solo com ambos os substratos e clones. As mudas com torrão apresentaram maior produtividade precoce no outono e inverno. Tanto as mudas com torrão como as de raízes nuas alcançaram elevada produtividade total. Concluiu-se que os novos clones selecionados podem ser indicados em substituição ou em combinação com as cultivares atualmente em uso no RS e que o sistema fechado sem solo é uma alternativa sustentável para ser empregada na produção de mudas com raízes nuas e de pontas de estolão para mudas com torrão.

This research was conducted to determine the effect of potassium (K) and cultivar on important quality traits of tomato (Solanum lycopersicum L.), including reducing sugar, titratable acidity, and vitamin E content. Tomato plants were grown in a soilless system. Three K levels (low, middle, and high equal to 150, 300, and 450 mg·L−1 in the nutrient solution, respectively) and three cultivars (SVR, Kabiria, and Esperanza) were compared. Among cultivars, Kabiria, which is characterized by smaller fruits, showed 23% higher total soluble solids (TSS) than the average of the other cultivars. ‘Kabiria’ also showed a total tocopherol (vitamin E) content (18.5 mg·kg−1), markedly higher than SVR and Esperanza cultivars (12.2 and 10.3 mg·kg−1, respectively). Increased K levels in the nutrient solution resulted in increased contents of TSS, reducing sugar contents and titratable acidity in tomato fruits. Also, the vitamin E content of tomato fruits was significantly affected by differing K concentrations in the nutrient solution.

[SPA] En los últimos años se ha producido un importante aumento del interés por el cuidado del medio ambiente y la obtención de alimentos más seguros y saludables. Como consecuencia, se han buscado formas de cultivo alternativas a la convencional, como el cultivo ecológico (E), producción integrada (PI) y cultivo sin suelo (SS). Existen evidencias de que el sistema de cultivo adoptado puede influir sobre la calidad de los productos hortícolas. La actividad antioxidante es un parámetro de calidad que proporciona una medida de la capacidad de un compuesto para proteger del efecto perjudicial de los procesos oxidativos y a la que se le ha atribuido capacidad para prevenir enfermedades cardiovasculares y diversos tipos de cáncer. El objetivo de este trabajo ha sido estudiar la influencia de los diferentes sistemas de cultivo (E, PI y SS), sobre la actividad antioxidante, tanto en la fracción hidrofílica (AAH) como en la lipofílica (AAL) del fruto de pimiento. El estudio se realizó sobre pimientos variedad Quito, en sus estados de maduración verde y rojo. Se realizaron tres muestreos consecutivos en 8 invernaderos comerciales de cada uno de los tres sistemas de cultivos. Los resultados obtenidos mostraron una mayor actividad antioxidante de los pimientos rojos respecto a los verdes en todos los sistemas de cultivo. A su vez, se encontró que la fracción con mayor actividad antioxidante fue la hidrofílica, tanto en fruto verde como rojo. La actividad antioxidante se vio significativamente afectada tanto por el tipo de cultivo como por la cosecha, en las dos fracciones estudiadas. En general, el sistema de cultivo SS dio como resultado frutos con mayor AAH y AAL que los cultivados bajo PI y E. Sin embargo, los cambios observados a lo largo del ciclo de cultivo muestran que la época de recolección puede afectar a la actividad antioxidante del pimiento en mayor medida que el sistema de producción. [ENG] In recent years consumer’s awareness of environmental protection and health and safecontrolled food has increased. As consequence, alternative production systems to the conventional one, such as organic (O), low-input (LI), and soilless (SS) systems, have been promoted. It has been shown that the production system can influence quality of horticultural products. Antioxidant activity is a quality parameter which provides a measurement of the ability of a compound to protect against oxidative processes. It has been recognised as beneficial for preventing some kinds of cancers and cardiovascular diseases. The aim of this study was to determine the influence of the different production systems (O, LI and SS) on the antioxidant activity, studying the contribution of the hydrophilic (HAA) and the lipophilic (LAA) pepper fraction. The study was carried on peppers cv. Quito in their green and red stage of maturation. Three consecutive harvests were performed in 8 commercial greenhouses of each production system. The results showed higher antioxidant activity in red than in Green pepper regardless of the cropping systems. In addition, HAA was higher than LAA regardless of the maturation stage. HAA and LAA were significantly affected for both the production system and the harvest time. In general, peppers grown under soilless system showed higher values of HAA and LAA than fruits under O and LI production. However, the fluctuations throughout the cultivation period show that harvest time can affect pepper antioxidant activity to a large extent than production system. Este trabajo ha sido financiado por la Fundación Séneca (05751/PI/07).

Tomato plants cv Naomi were grown in posidonia (Posidonia oceanica (L) Delile) with two NaCl salinity levels in nutrient solution (EC: 3 and 6 dSm-1) or with the NaCl level 3 dSm-1, in the most frequently used substrate in soilless systems, eg rockwool, to determine the effect of substrate or EC on yield, contents of minerals, antioxidants with nutritional and health values (vitamin C, lycopene, alfa-tocopherol and glutathione) as well as parameters affecting the organoleptic quality in cherry tomato fruits. Total yield was not influenced by substrate, but it was higher with 3 dSm-1 than 6 dSm-1 salinity. The yield reduction was compensated by the improvement of dry matter, total soluble solids, vitamin C and alfa-tocopherol, while lycopene and glutathione contents were not affected by NaCl. On average, when tomato plants were grown in the presence of the higher NaCl level, the fruit diameter was between 25 and 35mm (considered optimal for cherry tomato) while, with 3 dSm-1, it was greater than 35mm.