Abstract
Models simulating the effects of water stress on crop growth can be valuable tools for improving water management. PILOTE, an operative crop model, and CropSyst, a more sophisticated one, are compared on the basis of the simulation of silage maize ( Zea maize L.) growth for 2 years (2009–2010) under different water supply regimes in the semi‐arid climate of Tadla (Morocco). Both based on Beer's law via the intercepted potential active radiation (IPAR) regarding dry matter accumulation, the models differ in the level of complexity describing crop development, biomass growth, root water uptake principle and consequently, in the number of input parameters. The models were calibrated on an unstressed irrigation treatment in 2009, and were validated on other stressed and unstressed treatments in 2009 and 2010. Although PILOTE required fewer input parameters and data than CropSyst, it performed similarly and often better when simulating both biomass and soil water balance. Therefore, for water management purposes only, the use of a simpler model such as PILOTE can be recommended. Copyright © 2013 John Wiley & Sons, Ltd.