Crop yield prediction using CERES-Rice vs 4.5 model for the climate variability of different agroclimatic zone of south and north-west plane zone of Bihar (India)

Abstract

CERES-rice models are being validated and tested across the world and vigorously used in agrotechnology transfer. Crop growth models have been considered as potential tools for simulating growth and yield of crops. Hence, DSSAT v 4.5/ CERES-Rice (Decision Support System for Agro-technology Transfer / Crop Estimation through Resource and Environment Synthesis) was applied to validate the Rice productivity from Bihar State in India. Long term historical weather data (1980-2011) and (1985-2011) from South and North West Alluvial plane zones of Bihar was used for yield analysis. Genetic coefficients required for running the CERES-Rice vs 4.5 model were derived and the performance of the model was tested under the climate variability conditions experienced by these two agroclimatic zones. Management combinations simulated were three transplanting dates (1st, 15th & 30th July) for rice cultivar Rmansuri under rainfed conditions. The results indicated that both the early and late sowing dates result in lower yields as compared to optimum sowing date of 15th July. The simulated phenology and yield were found to be in agreement with observed data suggesting that the calibrated model may be operationally used with routinely observed soil, crop management and weather parameters for Rice yield estimation from these two regions of Bihar. The analysis also brought out that the yield differences under potential and rainfed condition during the study period, was influenced by variations in thermal, radiation regime as well as moisture regimes. The results showed that phenological stage of panicle initiation to grain filling is sensitive to water and Nitrogen availability status in the Rice Crop. This model is also satisfactory in predicting the Rice phenology. These results indicate that the CERES rice vs 4.5 models is capable of estimating growth stages and grain yield of rice cultivar Rmansuri in climatic conditions of Bihar with reasonable accuracy and hence show potential for its use as a tool in making various strategic and tactical decisions related to Agriculture planning in the state of Bihar.