Evaluation of AquaCrop and WOFOST to Simulate Potato Yield under Different Water Stress Conditions

Due to importance of potato plant, simulating its yield under water stress using plant growth simulation models helps researchers to better plan for irrigation. So, this study was conducted to evaluate water driven (AquaCrop) and carbon driven (WOFOST) to simulate potato yield under different water deficit during various cropping stages. To do this end, data collected from a research station in ChaharTakhteh, Shahrekord, during two years (1998-1999) was used. The data was consisted of water stress at five levels (E0, E1, E2, E3, and E4 indicating 100, 85, 70, 50, and 30 percent of crop water needed, respectively) in three time (T1, T2, and T3 indicating 50, 100, and 150 days after sowing, respectively). RMSE values for simulation of yield using AquaCrop and WOFOST were 1.5 and 2.2 ton.ha-1, respectively. Model efficiencies based on EF values were 0.95 and 0.98, respectively. According to MBE and NRMSE values, AquaCrop accuracy was better than WOFOST. In both calibration and validation period, AquaCrop suffered from under estimate error and WOFOST suffered from over-estimate error. Regarding the results, it is recommended to use AquaCrop for simulation potato yield since it needs less data, have better precision and easier calibration.