Validation of Ceres-maize model for simulating growth and yield of winter maize (Zea mays L.) under Punjab conditions

The crop environment resource synthesis model for maize was used to simulate growth and yield of winter maize at the Punjab Agricultural University, Ludhiana during winter season of 2002–03 with two dates of planting (November 10 and November 22) and six irrigation schedules (irrigation at pre-tasseling stage at 55 (I₅₅), 70 (I₇₀), 85 (I₈₅) and 100 mm (I₁₀₀) cumulative pan evaporation (CPE) followed by at 60 mm CPE at post tasseling stage, irrigation as recommended schedule (I_Rec) and another based on soil water balance model (I_M). The thermal time based phenological events (emergence and physiological maturity) were accurately predicted by model but it fails to predict photothermal-based events (tasseling and silking). The predicted LAI matched well with observed during early vegetative phases and physiological maturity but an over estimation was observed during all other stages of growth. The predicted dry matter matched well with field observed values during early vegetative growth but an overestimation was observed during later phases of growth. The predicted grain yield ranged from 98.9 to 116.5 percent of the actual observed yields under both the dates of planting. The results obtained with model showed that CERES model could be used to estimate final grain yield of winter maize under Punjab conditions.