Evaluation the Effects of Using Treated Wastewater on Soil Characteristics, Yield and Water Productivity of Quinoa

Since the sustainable agriculture field is the main water consumer, using techniques in order to increasing water use efficiency is necessary. An investigation was done to evaluate effects of different regimes of urban wastewater on chemicals properties of soil, yield and water productivity of Quinoa plant (cv. Titicaca), at Research Greenhouse of Ferdowsi University of Mashhad, during 2017-2018. The research was based on completely randomized design with three replications in greenhouse conditions and in pots. Five applied treatments were urban fresh water, urban wastewater, alternate wastewater and fresh water, mixture of 50-50 percent wastewater and freshwater, and subterranean irrigation with urban wastewater. The results show that the treatments were significant on K, P, N, and water productivity; grain yield was significant at 1 percent level (P<0.01), but on pH and 1000 kernel weights at 5 percent level (P<0.05). The research shows effects of using urban refined wastewater on an increase in all traits. The treatments of urban wastewater, alternate, mixture of 50-50 and subterranean irrigation resulted in an increase of 30.7%, 8.8%, 20.6% and 36.1% of grain yield, 31.1%, 8.6%, 20.5% and 36.4% of water productivity, 8.8%, 6.7%, 7.5% and 9.6% of 1000 kernel weights, respectively. Furthermore, the results of the experiment show that the use of refined sewage water for irrigation of Quinoa crop can increase the yield of Quinoa, positive effects on the chemical properties of the soils of the studied, and decrease the cost of supplying and using fertilizers, and then save the environment.