Using the PILOTE Model to Improve Water Productivity for Rice in Rasht, North of Iran

In order to calibrate and validate the PILOTE model for rice in a humid climate, this study was carried in a randomized complete block design with three replications on a popular local variety, Hashemi, during 2001, 2002, 2005, 2006 and 2007 crop seasons. This research was done at the Rice Research Institute of Rasht, Iran. Evaluation of simulated and measured grain yield and dry matter values was done using Nash-Sutcliffe efficiency (EF), Root Mean Square Errors (RMSE) and normalized root mean square errors (NRMSE) indices. The results revealed that RMSE for validation and calibration were 0.69 and 0.72 Mg.ha-1, respectively. NRMSE for calibration was 9.5 % and for validation was 14.1 %. NRMSE for grain yield and dry matter were 8.74 and 13.37 %, respectively. EF values were between 0.84 and 0.98. The results showed that the PILOTE model can be used to manage properly rice irrigation in different regimes. Scenario analysis showed that the best irrigation regime was intermittent irrigation with 8-day interval.