Evaluation of Physico-Economical Productivity of Water in Different Methods of Planting and Irrigating Rice cv. Fajr in Golestan Province

Rice is one of the important food products that is generally transplanted. The rice “dry seeding method (DSM)” is a new approach that has provided an opportunity to increase water productivity. In this research, changing the cultivation method from transplanting to DSM and using pressurized irrigation instead of flooding method was studied in 5 rice fields in Golestan Province. The field with flood irrigation method was considered as the control treatment. Other fields were cultivated in dry soil and irrigated by drip and sprinkler methods. The results showed that, in all parameters related to grain yield and yield components, the field with flood irrigation method had higher values. Economic study at the different growth stages with different irrigation methods showed that by changing the planting method and removing the puddling in rice field, 4000 to 7000 cubic meters of water can be saved. Comparison between different irrigation methods showed that the sprinkler irrigation had a higher average yield (4998 kg/ha) than drip irrigation) 4426 kg/ha(. With 30% yield reduction, this method saved 61% in water use, which is a significant amount. The highest and lowest physical (0.53 and 0.3 kg/m3) and economical productivity rates (141,791 and 82,704 Rials/m3) were related to sprinkler irrigation and flood irrigation, respectively, which show very low water productivity in the rice fields of the province. This shows the need to increase water productivity under the current climatic conditions of the country.