A methodology for model-based greenhouse design: Part 2, description and validation of a tomato yield model

With the aim of developing a model-based method to design greenhouses for a broad range of climatic and economic conditions, a tomato yield model that describes the effects of greenhouse climate on yield was described and validated. A literature survey of temperature effects on tomato yield was performed and the main temperature effects were implemented in the model. Subsequently, the yield model was validated for four temperature regimes. Results demonstrated that the tomato yield was simulated accurately for both near-optimal and non-optimal temperature conditions in the Netherlands and southern Spain, respectively, with varying light and CO2-concentrations. In addition, the adverse effects of extremely low as well as high mean temperatures on yield and timing of first fruit harvest were simulated with fair accuracy. The simulated yield response to extreme diurnal temperature oscillations were in agreement with literature values. Given these results, the model is considered to be sufficiently accurate to be used for developing a model-based greenhouse design method. Therefore, the presented model will be integrated in a model-based design method with the aim to design the best greenhouse for local climate and economic conditions