Crop Water Production Function of Processing Tomato (Solanum lycopersicum) under Regulated Deficit Irrigation

An experiment was conducted to determine the water sensitivity index (WSI) and water production function (WPF) of processing tomato under regulated deficit irrigation (RDI) in an arid environment. The WSI at different growth periods of processing tomato was maintained and a periodical WPF was established based on Jensen model. The maximum WSI was maintained at flowering with 0.8122 while the minimum was marked at seedling with 0.0589. In addition, WSI at full fruiting was much lower than at flowering but higher than at late fruiting. Therefore, processing tomato was extremely sensitive to water deficit at flowering and enough water should be applied to crops to maintain a high yield, while processing tomato was not sensitive to water deficit at seedling and a high level of water deficit could be reasonably controlled at this period through RDI without causing yield reduction.