A decision support system (DSS) for estimating tomato growth and mineral uptake in greenhouse soilless system

In the last decades, there has been intense scientific and technological research aimed at increasing the efficiency of water and fertilizers use in greenhouse crops particularly in soilless cultivation. The approach for managing soilless systems in protected cultivation in a more sustainable way includes the use of decision support systems (DSS) with simulation models to estimate the water and mineral requirements under various growing conditions. The VegSyst model developed at the University o Almeria (Spain) simulates, on a daily basis, the biomass production evapotranspiration, and uptake of major nutrients (N, P, K, Ca, and Mg) in greenhouse soil-grown vegetables. In the present study, the VegSyst model was calibrated and validated in two separate experiments carried out in a glasshouse at the University o Pisa (Italy) with a Tuscan landrace tomato (Pisanello), which is highly appreciated for its taste. Tomato plants were grown in a semi-closed substrate (stone wool) culture. The uptake of N, K and Ca was adequately simulated with the original model parameters determined for soil-grown tomato, while for P and Mg a new calibration was necessary due to the different bioavailability of these mineral nutrients in soil and in artificia substrate. This DSS based on the VegSyst model successfully simulated the biomass and nutrient uptake of key ions, such as N, P, K, Ca and Mg in soilless tomato crops. This approach can help Mediterranean tomato greenhouse producers optimize water and fertilizer usage.