Effect of Soil Suction Threshold Value of Irrigation Management and Crop Rotation on Yield and Water Use Efficiency of Maize

Given the potential of modern irrigation system, it is important to perform intelligently irrigation, or in other words, determine the time, place and amount of water in order to maximize water use efficiency in the face of water shortages. This study was conducted to examine the effect of different levels of soil suction threshold before irrigation and crop rotation on yield and water use efficiency of maize in loam soil under drip-tape irrigation system. The three irrigation management levels contain; irrigation based on ETC calculation using FAO-PM equation (W1), soil moistures suction levels of 40 kPa (W2), and 20 kPa (W3), and two crop rotation contains; fallow-maize (Nfal) and wheat-maize sequence (Nseq). Total biomass, and leaf area index during the growing season and grain yield at maturity stage were measured. The maximum total biomass, grain yield, and leaf area index were observed in NfalW3 treatment with 25 ton/ha, 12.6 ton/ha, and 5.3 m2/m2, respectively. The difference between water use efficiency and irrigation water use efficiency was lowest in the third level of irrigation management, indicating a precise irrigation based on the water requirement of the plant and reducing evaporation and penetration losses.