Effect of partial root-zone drying on yield, yield components and water use efficiency of tomato (Solanum lycopersicum L) under conditions deficit irrigation

Deficit irrigation is one of the limiting factors of crop production. An experiment in a split plot randomized complete block design with three replications on tomato in Ferdowsi University of Mashhad, Iran, during the 2018 cropping season. Treatments included; usual irrigation, fixed partial root-zone drying and alternative partial root-zone drying (main plot) and deficit irrigation100, 75, 50% irrigation requirement (sub plot). Effect irrigation methods and different levels of deficit irrigation had significant on number, weight, diameter, firmness, vitamin C and pH fruit. Maximum shoot dry weight of 153.96 g.plant-1, number of fruits per plant (58), number of fruits per square meter (163), single fruit weight 46.03 g, fruit diameter 98.48 mm, vitamin C 9.47 mg.gfw-1, fruit yield 4.46 kg.m-2 was observed in usual irrigation method. The highest amount of lycopene was 84.85 mg.gfw-1, fruit firmness 3.93 Kg.cm-2, pH 4.58, water use efficiency of 4.46 kg.m-3, 2 was observed in fixed partial root-zone drying irrigation. The results showed that the highest yield among irrigation methods, respectively in conventional irrigation method, ; usual irrigation, fixed partial root-zone drying and alternative partial root-zone drying and maximum water use efficiency in fixed partial root-zone drying irrigation method and 75% water requirement observed.