Simulation of Grain Yield and Biomass of Corn at Different Irrigation Regimes and Nitrogen Application

DSSAT-CMS computer model simulates growth, development and crop production under the management conditions such as variation in soil moisture, soil carbon, soil nitrogen and nitrogen leaching. In this study, first CERES-Maize model with 20% moisture depletion and then grain yield and biomass of corn at harvesting time were calibrated. Calibration coefficients for corn single cross 260 were P1=169, P2=0.386, P5750, G2=775.9, G3=8.82 and PHINT39.20. Results showed that the model estimates grain yield and biomass in normalized mean root of error squares (RMSEn), Wilmot agreement index (d) and correlation (R2) coefficient at 18, 90 and 82 percent and 29, 84 and 84 percent respectively. Therefore, CERES-Maize model has the high precision in simulation of these two traits and also simulation was desirable in Shiraz region. The model simulated grain yield better than biomass. In general, the model can be used for irrigation and nitrogen management in the region.