Application of CSM-CERES-Rice in scheduling irrigation and simulating effect of drought stress on upland rice yield

Crop models can provide rapid and cost effective means to deal with rice crop management. The objectives of this study included, exploring theability of CSM-CERES-Ricein scheduling irrigation and to simulate the effect of drought stress on upland rice yield. Irrigation treatments 100, 70 and 50% of field capacity (FC) were applied from 80 days after planting (DAP) at flowering stage until maturity and CSM-CERES-Rice was used to predict irrigation amount for each water regime for treatment duration. Results showed that, at 70 and 50% FC, performance of an upland rice genotype, Dawk Payawm was decreased significantly as compared to 100% FC. Normalized root mean square error (RMSEn) values less than 10% for each treatment indicated a strong agreement between simulated and observed grain yield (GY) and biomass. d-index approaching to unity and RMSEn less than 10% indicated a good agreement between simulated and observed soil moisture contents (SMC) for all irrigation treatments. Overall, it was concluded that drought stress had negative correlation with GY and CSM-CERES-Rice was able to predict irrigation amount for all treatments assuring that, model has potential for its use as a tool to schedule irrigation for experiments under water limited conditions.