Performance of AquaCrop Model in Simulating Tuber Yield of Potato (Solanum tuberosum L.) under Various Water Availability Conditions in Mekelle Area, Northern Ethiopia

Abstract

Potato is sensitive to high temperature and moisture deficits which could be one of the major reason for low potato production in Ethiopia. The objective of this study was to validate and apply AquaCrop model for devising better water management strategies for optimal potato production in the region based on experimental data conducted at Mekelle areas (Mekelle University (MU) and Mekelle Agricultural Research Center (MARC)) during the cropping season in 2012; There were three treatments of water: Full Supplementary (FSI), Deficit Irrigation (DI) and Rainfed (RF) laid out in RCBD with three replications. AquaCrop model was calibrated and validated to simulate the observed WUE, growth and yield of potato. Results of the statistical parameters showed that AquaCrop model was able to accurately simulate the final dry tuber yield (E=0.96 and NRMSE=3.49%), water use efficiency (E=0.33 and NRMSE=13.8%), and total biomass (E=0.72 and NRMSE=7%) at MU site. Similarly, the model was able to simulate final tuber yield (E=0.84 and NRMSE=8%) and WUE(E=0.49 and NRMSE=1.58%) at MARC. Whereas, biomass yield was not accurately simulated by the model (E=-1.81 and NRMSE=27.1%) for MARC site. Thus, AquaCrop model could be used for planning and predicting irrigation management purposes.

Key words: AquaCrop model, Calibration, Validation, Simulation