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Development of a Warning System for Controlling Botrytis cinerea in Unheated To...
Baptista, Fátima J.; Bailey, B.J.; Meneses, J.F.Botrytis cinerea is the causal agent of grey mould disease which is one of the most important diseases affecting tomato crops in unheated greenhouses. As a prophylactic measure growers usually apply large quantities of chemical fungicides for its control. Nocturnal ventilation is an effective way to reduce high relative humidity inside greenhouses and can be a useful tool to minimise chemical use in unheated gr...
CONSUMO DE ENERGIA E CUSTOS DE AQUECIMENTO NA PRODUÇÃO DE FLORES E LEGUMES EM E...
Meneses, Jorge F.; Baptista, Fátima J.Pretende-se determinar os consumos de energia e os custos em aquecimento, na produção de flores e de vegetais, ao longo do ano, em estufas de plástico aquecidas, localizadas em diversas zonas de produção de culturas forçadas. No primeiro ano considerou-se Portugal e a produção de rosa. Foram calculados os consumos energéticos e os custos de aquecimento com gasóleo ou gás natural, para duas combinações de temper...
Forced ventilation and evaporative cooling of waiting and milking areas and its...
Amaral, R.S.; Chaves, Modesto; Teodoro, Sônia; Fitas da Cruz, Vasco; Baptista, Fátima J.The main objective of this work was to evaluate the effect of forced ventilation and evaporative cooling on the physiological and production responses of dairy cows Holstein × Zebu. Experiments were conducted with 32 crossbred cows (Holstein × Zebu) in the same lactation phase, mean daily production of 17 kg and mean body weight of 550 kg. Four different treatments were randomly assigned to groups with eight ...
Comparion of humidity conditions in unheated tomato greenhouses with different ...
Baptista, Fátima J.; Bailey, B.J.; Meneses, J.F.The objective of the research was to investigate the influence of nocturnal ventilation on the humidity conditions in unheated tomato greenhouses and the consequences for Botrytis cinerea control. Experiments were carried out at the Instituto Superior de Agronomia in Lisbon in two identical adjacent double-span greenhouses covered with three layer co-extruded film. The climate was controlled by natural ventilat...
Comparison of Four Natural Ventilation Systems in a Mediterranean Greenhouse
Coelho, M.; Baptista, Fátima J.; Fitas da Cruz, Vasco; Garcia, José LuísVentilation is one of the most important tools for controlling the greenhouse climate, influencing the environmental conditions such as temperature, humidity and carbon dioxide concentration, which affect the development and production of the crop. Natural ventilation is the result of the action of two natural forces, wind and thermal buoyancy. The main objectives of this study were to: 1). compare the behaviou...
Determinação de coeficientes de transferência de calor por convecção em estufas.
Baptista, Fátima J.; Meneses, J.F.A determinação dos coeficientes de transferência de calor por convecção (hc) é complexa, encontrando-se com frequência, expressões e valores obtidos pelo ajuste de resultados experimentais a modelos climáticos. É de salientar que em muitos destes casos não se tem em conta a natureza do processo de transferência envolvido. O objectivo deste trabalho é a determinação dos vários coeficientes cobertura_ar exterior,...
Measuring and Modelling Transpiration Versus Evapotranspiration of a Tomato Cr...
Baptista, Fátima J.; Bailey, B.J.; Meneses, J.F.The main sources of water vapour in a greenhouse are plant transpiration and the evaporation of water from soil (evapotranspiration). These processes are influ- enced by environmental factors such as solar radiation and water vapour pressure deficit, as shown by the Penman-Monteith equation. Most previous studies have been conducted in Northern countries and with soiless crops, which means th...
VALIDATION AND COMPARISON OF A PHYSICAL AND A STATISTICAL DYNAMIC CLIMATIC MODE...
Baptista, Fátima J.; Litago, J.; Navas, L.M.; Meneses, J.F.This study is based on the experiments with a tomato crop, carried out in a Mediterranean unheated greenhouse, located at Lisbon. The main objective is to study the comparative performance of a physical and a statistical model to explain and forecast the dynamic of the greenhouse climate, validating their results. External and internal climatic data as well as information on the evolution of the crop were colle...
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