Assessment of AquaCrop Model for Simulating Spring Canola Yield and Soil Water under Water Stresses

Rapeseed is the most important edible oil source after soybean and palm in the world and is the most widely cultivated oilseed crop in Iran. The objective of this study was to adapt and test the ability of the AquaCrop model to simulate canola grain yield, biomass and soil water content. In this study, the dynamic simulation model AquaCrop for plant growth under conditions of limited water spring was used in climate Tabriz. The experimental design included four treatment I1, I2, I3 and I4 respectively regular watering of rape, 20, 35 and 50 percent less than its potential needs in four replicates in a randomized complete block design was carried out for two years 2010 and 2011. AquaCrop model using the measured data in 2010 calibration and validation data were measured in 2011. Based on found results, the AquaCrop model predicted the GY at maturity with a good precision and soil water simulated by AquaCrop tends to follow closely the trend in the measured data. In general, statistical indicators NRMSE and d for the final performance of the product (7.05%, 0.96), soil water content (16.03% and 0.77), respectively. Also Errors in the model’s evaluation such as average NRMSE statistics were for dynamic biomass in the calibration and validation process 29.31 and 20.38%. The overall results showed that AquaCrop is a valid model and can be used with a reliable degree of accuracy for optimizing canola grain yield production and water requirement in the region Karkag of Tabriz.