Effect of Treated Municipal Wastewater Usage On Corn Yield and Yield Components Under Deficit Irrigation Management (Case Study: Marvdasht, Fars Province)

In the face of increasing urban wastewater and the fact that the country's water resources are not only limited but also declining, increasing water use efficiency and reuse of municipal wastewater is inevitable. This study was conducted to investigate the use of municipal wastewater on yield, yield components and water use efficiency in forage maize with two factors: a) Use of wastewater in three levels (1- well water (W), 2- One to one mixture of well water and wastewater (50 50) and 3- Wastewater (WW) b) Management of traditional low irrigation at four levels (normal irrigation (100% irrigation requirement)) and low irrigation at 40, 60 and 80% levels of water requirement) in the form of a randomized complete block design with 12 treatments and three replications in the field of Marvdasht municipal wastewater refinery plant in 2018. Statistical indicators such as maximum error, coefficient of determination, mean square root of the error, modeling efficiency and residual coefficient were used to quantitatively evaluate the functions. Plant susceptibility coefficient (Ky) for total dry matter in three stages of vegetation, flowering and grain ripening were 0.38, 0.52 and 0.63, respectively, and it was found that the most sensitive stage of corn growth to water deficiency is the stage of grain ripening. Analysis of interactive effects showed that the highest total dry matter yield in vegetative and flowering stages and grain yield in grain growth stage were 7260, 9857 and 3158 kg/ha in WW-FI treatment (complete irrigation with wastewater) and the lowest yield with the values of 5052, 6069 and 1508 kg/ha were obtained in W-DI60 treatment (60% low irrigation with well water). The results showed that the use of wastewater in low traditional irrigation conditions is useful for forage maize and can be recommended.