Simulation of the growth and the production of the tomato in typical greenhouses of the Mediterranean environment

For some time plant cultivation in greenhouses has been evolving towards increasingly complex and technologically advanced forms. The introduction of new cultivars, new materials used for covering greenhouses, and more and more modern and sophisticated cultivation techniques and control systems enable us to achieve quantitative and qualitative improvements in production. There fore, our greenhouse growers can be competitive on the global market with countries which have low labor costs. These cropping systems, which give us the opportunity to overcome the traditional ripening times of the crops and therefore increase production due to a larger number of productive cycles per year, require large amounts of energy since the crops arc grown at times which differ from their normal growing cycle. In greenhouse cultivation these energy requirements are satisfied firstly by means of a proper use of a natural source (the greenhouse effect) and secondly by using artificial means such as heating and lighting. etc. In this context the characteristics of greenhouse crops and the planning are important for reducing the amount of artificial energy required and increasing the production obtained. The response of crops to changes of climatic parameters (PAR, temperature, relative humidity. CO) has been the subject of numerous studies which have led to the formulation of various mathematical simulation models. These models are useful for the management of the control systems of the climatic conditions in greenhouses and they may also be used in the planning of crops in order to reduce the energy inputs required for cultivation. For this reason the study was carried out using a mathematical simulation model of the growth of the plants, calibrated on real production values, in order to determine some planning criteria of the crops which enable us to obtain high crop yields using the lowest possible amount of energy in order to safeguard the environment.