Application of the CSM-CERES-Rice model for evaluation of physiological traits associated with rice yield

Abstract

The objective of this study was to evaluate the CSM-CERES-Rice model for simulating the physiological characteristics associated with rice yield. The field data used to validate the model was obtained from the experiment that was conducted in the farmers’ fields at Khum Thong sub-district, Lat Krabang district, Bangkok. Seven non-photoperiod sensitive rice cultivars consisting of Chainat 1, Suphan Buri 1, Suphan Buri 2, Suphan Buri 3, Pathum Thani 1, Pathum Thani 80 and Phitsanulok 2 were used. Randomized Complete Block Design (RCBD) with 4 replications was used as the experimental design. Three planting dates were selected, i.e. 13 February 2010 (planting  date 1), 15 August 2010 (planting date 2) and 16 January 2011 (planting date 3). Three plants were used per hill with a space of 25x25 cm. The soil, weather, management and plant data of the 3 planting dates were recorded. The CSM-CERES-Rice model was used to evaluate CGR, LAI and SLA at different growth stages similar to actual field conditions. Model evaluation was done by comparing the simulated values with their corresponding observed data using coefficient of determination (R2), normalized root-mean-square error (RMSEn) and index of agreement (d). The results showed that the model can be used to simulate CGR, LAI and SLA as indicated by good agreement in all planting dates, especially the CGR from 45 days after transplanting to harvesting which is the most important phase in contributing to the non-photoperiod sensitive rice yield.