Effect of partial root-zone drying and deficit irrigation on growth characteristics of tomato (Solanum lycopersicum L.)

Deficit irrigation is one of the ways to increase water productivity in irrigated lands. This study was conducted as a split plot experiment in a randomized complete block design with three replications on flat tomato cultivar at the Research Farm of Ferdowsi University of Mashhad, Iran, during the 2018 cropping season. Treatments included three irrigation methods including; usual irrigation, fixed partial root-zone drying and alternative partial root-zone drying as main plots and three levels of deficit irrigation (50, 75 and 100% of field capacity) as subplots. Results show that the highest and lowest concentration photosynthetic pigments observed in the alternative partial root-zone drying and the fixed partial root-zone drying respectively. Maximum plant height (68.8 cm) was observed in fixed partial root-zone drying. Results show that, the maximum leaf area index (2.15), stem dry weight (76.5 g.plant-1), leaf dry weight (72.6 g.plant-1) and fruit yield (4.50 kg.m-2) was found in 100% field capacity. According to the results of the present study, the best result observed in usual irrigation, fixed partial root-zone drying and alternative partial root-zone drying respectively. Fruit yield in fixed partial root-zone drying was more than the alternative partial root-zone drying method.