Model-based smart irrigation control strategy and its effect on water use efficiency in tomato production

Drip irrigation's potential to conserve irrigation water by around 25% compared to conventional methods is widely acknowledged. Nevertheless, the influence of varied irrigation control strategies on drip irrigation's impact remains uncertain, particularly regarding crop growth parameters and water use efficiency. In this study, we examine the effects of three distinct irrigation control approaches manual, model-based, and open-loop on drip-irrigated tomato plants within an open field agricultural context. Employing a completely randomized design, we cultivated 160 tomato plants and administered irrigation water according to each strategy's water requirements. Comprehensive data on key crop growth indicators, including plant height, stem diameter, leaf chlorophyll content, clusters per plant, flower and fruit counts, yield, and water use efficiency were documented. The results emphasize the pivotal role of the model-based irrigation control strategy. Specifically, this approach yielded a substantial tomato yield increase, recording 20 t/ha, in contrast to the 16 t/ha and 14 t/ha achieved by the open-loop and manual strategies, respectively. Noteworthy, the model-based approach exhibited remarkable water savings of 10.4 kg/m3, surpassing the values of 7.1 kg/m3 and 5.6 kg/m3 obtained through the open-loop and manual strategies. These differences proved statistically significant, evidenced by a p-value of 0.05. The model-based irrigation strategy led to a 29% reduction in water consumption compared to manual control. This study establishes the model-based irrigation strategy's superiority, showcasing elevated tomato yield and improved water use efficiency. These findings furnish valuable insights into sustainable agricultural practices, particularly in the realm of drip irrigation systems.