Pantnagar Journal of Research

Abstract

APSIM-Wheat and CERES-Wheat, which simulates yield has been calibrated for wheat using experimental data of 2017-18 crop season under Tarai region of Uttarakhand. The calibration was performed against anthesis (DAS), physiological maturity (DAS), grain and biomass yield for the three treatments of sowing dates (viz.,15^th November, 25^th November and 05^th December), three levels of irrigation (number of irrigations five, four and three) for two wheat varieties (HD-2967 and PBW-502). The calibrated APSIM-Wheat and CERES-Wheat model were then applied validated for rabi season of 2018-19. The CERES model shows superior performance compared to the APSIM model across several metrics. For days to anthesis, CERES RMSE values range from 2.75 to 3.69, while APSIM's are 3.78 to 5.77. For physiological maturity, CERES % RMSE values are 4.82 to 5.34, and APSIM's are 5.13 to 6.35. Biological yield R² values for CERES are 0.91 to 0.94, while APSIM's are 0.84 to 0.85. Grain yield RMSE values for CERES range from 2.11 to 3.16, compared to APSIM's 3.03 to 5.14, indicating that CERES predictions are closer to experimental data.