Optimizing the transplanting window for higher productivity of short and medium duration rice cultivars in Punjab, India using CERES-Rice model

Abstract

The CERES-Rice (V4.7.5) model was used to identify the optimum transplanting window for higher productivity of rice in Indian Punjab. The model was first sensitized for 11 genetic coefficients and then these values were used for calibrating and validating the model for rice cultivars. The Normalized Root Mean Square Error was in excellent range (< 10%) for all the parameters—the coefficient of determination (R2) for CVS. PR126 and PR127 for days taken to anthesis and maturity were 0.94 and 0.89−0.96, respectively while grain yield and LAI (leaf area index) were 0.89−0.98 and 0.87−0.89, respectively. The optimum transplanting window of 24−30 June for PR126 and 20−26 June for PR127 simulated the grain yield/LAI ranging from 8,425−8,473 kg·ha−1/4.23−4.24 for PR126 and 8,298−8,356 kg·ha−1/4.20−4.21 for PR127. The early transplantation of rice cultivars on 7th June resulted in the lowest yield/ LAI of 6,702 kg·ha−1/3.8 for PR126 and 6,865 kg·ha−1/3.9 for PR127. The deviation for the grain yield and HI (harvest index) of PR126 was between −14.2% to +8.2% and −15.1% to +10.5%, respectively, and of PR127 varied between −11.2% to +8.1% and −14.2% to +10.6%, respectively. The decline in the yield/HI from the average was observed during early transplantation in 2nd week of June (before the 15th of June for PR126 and the 13th of June for PR127) as well as late transplantation in the 1st week of July (after 11th July for PR126 and 6th July for PR127) for rice cultivars. The negative effect on yield and HI of both varieties during early and late transplantation could be due to unfavorable climatic conditions.

Keywords

• calibration
• dssat
• sensitivity index
• simulation modelling
• validation
• rice