Evaluation of AquaCrop Model to Simulate Corn Yield under Water deficit and Superabsorbent application

Deficit irrigation and application of superabsorbent are methods to increase water use efficiency. Regarding the purpose, In order to simulate corn growth and yield by considering deficit irrigation and superabsorbent polymer application, AquaCrop model have been used due to its capabilities. This study was conducted as a split plot based on the randomized complete block design (with 12 treatments and three replicates) at a research field during 2016, in Ahvaz. Treatments consist of irrigation amount (in three levels; I1, I2 and I3 as 100, 75 and 50% irrigation demand, respectively) and superabsorbent polymer application (at four amounts; S0, S1, S2 and S3 as zero, 0.3, 0.6 and 0.8 g.kg-1 soil, respectively). The greatest difference between simulated and measured output was obtained in I2S2 and the lowest one was measured in I1S0. Values of RMSE for grain yield, biomass, water use efficiency and harvest index were 0.72 ton.ha-1, 1.35 ton.ha-1, 0.2 kg.m-3 and 0.07, respectively. Values of MBE for mentioned parameters were -0.09 ton.ha-1, 0.65 ton.ha-1, -0.02 kg.m-3 and -0.01, respectively. NRMSE and d values ranged between 0.47-0.95 and 0.13-0.23, respectively. Values of EF and R2 were also appropriated in this research. So, According to results, it is suggested to use this model for simulation of corn yield and growth.