The integration of renewable energy sources into greenhouse crop production in southeastern Spain could provide extra income for growers. Wind energy could be captured by small to medium-sized wind turbines, gas could be produced from biomass, and solar energy could be gathered by solar panels. The aim of this study was to examine the effect of flexible solar panels, mounted on top of a greenhouse for electricity production, on yield and fruit quality of tomatoes (Solanum lycopersycum L., cv Daniela). This study was undertaken in a commercial raspa y amagado greenhouse, typical of the Almería region (Spain). Tomato plantlets were planted at a density of 0.75 plants m −2 . The flexible solar panels were mounted on two parts of the roof in different arrangements (T1 and T2), each blacking out 9.8 % of its surface area. A control area (T0 arrangement) was fitted with no panels. No difference was found in terms of total or marketable production under these three arrangements, although fruit mean mass and maximum diameter of T0 were significantly greater than T1 and T2. Fruit in T0 matured earlier with more intense color compared with those in T1 and T2. However, these differences had no effect on price as the tomatoes produced under three conditions fell into the same commercial class (G class; diameter 67-81 mm). Solar panels covering 9.8 % roof area of the greenhouse did not affect yield and price of tomatoes despite of their negative effect on fruit size and color.

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The purpose of this study was to demonstrate interest in applying simple and multiple logistic regression analyses to the marketability probability of commercial tomato (Solanum lycopersicum L.) cultivars when the tomatoes are harvested as loose fruit. A fruit’s firmness and commercial quality (softening or over-ripe fruit, cracking, cold damage, and rotting) were determined at 0, 7, 14, and 21 days of storage. The storage test simulated typical conditions from harvest to purchase-consumption by the consumer. The combined simple and multiple analyses of the primary continuous and categorical variables with the greatest influence on the commercial quality of postharvest fruit allowed for a more detailed understanding of the behavior of different tomato cultivars and identified the cultivars with greater marketability probability. The odds ratios allowed us to determine the increase or decrease in the marketability probability when we substituted one cultivar with a reference one. Thus, for example, the marketability probability was approximately 2.59 times greater for ‘Santyplum’ than for ‘Angelle’. Overall, of the studied cultivars, ‘Santyplum’, followed by ‘Dolchettini’, showed greater marketability probability than ‘Angelle’ and ‘Genio’. In conclusion, the logistic regression model is useful for studying and identifying tomato cultivars with good postharvest marketability characteristics.

The purpose of this study was to identify the effects of using aluminised screens offering different degrees of shading on the production and quality of tomato cv Atlético crops grown under greenhouse conditions. The study was performed in an Almería-type "raspa and amagado" commercial greenhouse with an area of 10,000 m 2 . The covering material was heat-insulating polyethylene (200 µm thick). The passive ventilation area of the greenhouse was 14%. Transplantation of the plantlets into the sandy mulch soil of the greenhouse was performed to leave a density of 1.78 plants m -2 . Plants were grown under extendable aluminised screens offering 40% (T40), 50% (T50) and 60% (T60) shading, as well as under traditional whitewashing conditions (control). The screens were used during the middle hours of the day in summer with a view to reducing radiation, and at night in autumn and winter to prevent the loss of heat via outgoing long-wave infrared radiation. Only the T60 treatment returned significantly different results compared to the control: the T60 fruit had a lower ºBrix but were firmer in both growing seasons.Additional key words: Brix degrees, climate control, firmness, fruit weight, pH, whitewashing. ResumenEfecto del sombreo mediante pantallas aluminizadas sobre la producción y calidad de fruto en tomate (Solanum lycopersicum L.) bajo invernaderoEl propósito del presente trabajo fue evaluar la posible ventaja del uso de las pantallas aluminizadas con diferentes proporciones de sombreo, sobre los principales atributos de producción y calidad en cultivo de tomate cv Atlético bajo invernadero. El estudio se realizó en un invernadero comercial tipo Almería de "raspa y amagado" de 10,000 m 2 . El material de la cubierta fue polietileno termoaislante de 200 µm de grosor y con un 14% de ventilación pasiva. El transplante se realizó en suelo arenado a una densidad de 1,78 plantas m -2 . El estudio comparó el uso de pantallas aluminizadas extensibles del 40% (T40), 50% (T50) y 60% (T60) de sombreo frente al testigo (encalado tradicional). Se utilizaron en los meses de verano durante las horas centrales del día con el objetivo de reducir la radiación y, en otoño e invierno, durante la noche para evitar la pérdida de temperatura por radiación infrarroja de onda larga. Tan sólo con T60 se obtuvieron diferencias significativas respecto del testigo, en ambas campañas, en cuanto a menor ºBrix y mayor firmeza del fruto. Un mayor sombreo produjo mayor firmeza y menor cantidad de sólidos solubles (ºBrix) en frutos.

Solar photovoltaic (PV) systems have grown in popularity in the farming sector, primarily because land area and farm structures themselves, such as greenhouses, can be exploited for this purpose, and, moreover, because farms tend to be located in rural areas far from energy production plants. In Spain, despite being a country with enormous potential for this renewable energy source, little is being done to exploit it, and policies of recent years have even restricted its implementation. These factors constitute an obstacle, both for achieving environmental commitments and for socioeconomic development. This study proposes the installation of PV systems on greenhouses in southeast Spain, the location with the highest concentration of greenhouses in Europe. Following a sensitivity analysis, it is estimated that the utilization of this technology in the self-consumption scenario at farm level produces increased profitability for farms, which can range from 0.88% (worst scenario) to 52.78% (most favorable scenario). Regarding the Spanish environmental policy, the results obtained demonstrate that the impact of applying this technology mounted on greenhouses would bring the country 38% closer to reaching the 2030 greenhouse gas (GHG) target. Furthermore, it would make it possible to nearly achieve the official commitment of 20% renewable energies by 2020. Additionally, it would have considerable effects on the regional socioeconomy, with increases in job creation and contribution to gross domestic product (GDP)/R&D (Research and Development), allowing greater profitability in agrifood activities throughout the entire region.

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This study investigates the use of the Labour Economics and Sociology Laboratory of France (LEST) method to analyse work posts among greenhouse workers in the Almería region of south-eastern Spain. The aim is to improve the health of the labourers. Data were gathered from 110 greenhouses, 73 of the Almería parral plano type and 37 raspa and amagado. Crops studied were 63 greenhouses of tomatoes, 31 of watermelons, and 16 of courgette, examining the physical environment, physical load, psycho-social aspects, and time worked by the labourers. The main conclusion was that this type of crop protective structure, typical in south-eastern Spain, does not guarantee a comfortable working environment, as defined by the norm UNE-EN 13031-1 reference. The results also associate the different types of greenhouses and their crops with the ergonomic and psycho-sociological conditions of the workers. Improvements are proposed.Additional key words: ergonomics, greenhouse, LEST, prevention, Psycho-sociology. Resumen Índices de calidad ergonómica-psicosociológica en invernaderos de Almería (España)Este estudio investigó el uso del método de LEST (Labour Economics and Sociology Laboratory of France) para evaluar los puestos de trabajo en invernaderos de la provincia de Almería (España). Todo ello, con el fin de mejorar la salud de los trabajadores. Los datos se han obtenido de 110 invernaderos, 73 del tipo Almería "parral plano" y 37 "raspa y amagado"; según el tipo de cultivo, 63 de tomate, 31 de sandía y 16 de calabacín, afectándose negativamente al entorno físi-co, carga física, aspectos psicosociales y tiempo de trabajo de los trabajadores. Como conclusión principal, este tipo de estructuras de protección de cultivos típicas del sudeste español no garantizan el trabajo de las personas de forma cómoda en su interior, no estando dentro de la definición de la norma UNE-EN 13031-1 de referencia, además los resultados asocian directamente los diferentes tipos de invernaderos y sus cultivos con las condiciones ergonómico-psicosociales de los trabajadores, proponiéndose mejoras para ellos.

The aim of this study is to establish a binary logistic regression method to evaluate and select cucumber cultivars (Cucumis sativus L.) with a longer postharvest shelf life. Each sample was evaluated for commercial quality (fruit aging, weight loss, wilting, yellowing, chilling injury, and rotting) every 7 days of storage. Simple and multiple binary logistic regression models were applied in which the dependent variable was the probability of marketability and the independent variables were the days of storage, cultivars, fruit weight loss, and months of evaluation. The results showed that cucumber cultivars with a longer shelf life can be selected by a simple and multiple binary logistic regression analysis. Storage time was the main determinant of fruit marketability. Fruit weight loss strongly influenced the probability of marketability. The logistic model allowed us to determine the cucumber weight loss percentage over which a fruit would be rejected in the market.