Utility of CERES-barley under Argentine conditions

The model CERES-barley was calibrated for five genotypes sown on five dates between June and September under optimal growing conditions. Then, the model was validated with data sets (n = 83) obtained under a wide range of environmental conditions covering different sowing dates, years, cultivars, fertility, soils and climates. Results of calibration showed differences between cultivars in their response to photoperiod, vernalization and in their dry-matter partitioning. In validating the model, the root mean square error (RMSE) obtained for flowering-date estimates was 5.6 days with a greater bias for the extreme sowing dates (early June and September). Grain yields corresponding to normal sowing dates (mid June-mid August) were adequately simulated; the bias was 15 kg ha(-1), its mean absolute error was 288 kg ha(-1) and the root mean square error 397 kg ha(-1), for observed values ranging between 2000 and 5500 kg ha(-1). We can conclude that under normal sowing dates CERES-barley is able to simulate grain yield reliably for Argentine conditions. (C) 1998 Elsevier Science B.V. All rights reserved.