Simulation of Wheat Yield under Different Irrigation Management by CropSyst in ZARAGHAN, FARS Province

Water is a limited and also essential source for the human societies and ecological systems which depend on it. This valuable source is decreasing rapidly because of population growth and economic development in many countries and regions of the world. In such situation, it is needed to increase water productivity. Plant models are used for optimization of management operations in variable environment. The model acts as an analyst tool on the fertility of the product and the environment. Crop growth model CropSyst is a comprehensive sample of a simulated model which is used in many region of the world so far. Due to the need reduction of visits and direct measurements in field, crop growth models can become effective in optimisation of water irrigation management and fertilization. This study is performed in the form of split plot plan based on RCB with two main factors, cultivar with 1levels and irrigation regimes with 8levels and 1repetitions. Cultivars are commercial cultivars named Falat, Shiraz and Chamran. Irrigation regimes were set based on the distance to the lateral pipe. In this study 1meter distances are considered for Irrigation regimes. Accordingly, moisture regimes were 5, 8, 11, 14 meter distances from lateral pipe. The experiment was done in the crop years 2013, 2014 and 2015. The data of the year 2013 and 2014 was used for calibration and 2015 for the validation of the model. nRMSE and Crm for the grain performance in calibration years was obtained 9.3 and 0.06 percent respectively and for the validation year 9.7 and 0.11 percent respectively. According to nRMSE statistic for simulation of grain performance, Crop growth model CropSyst works in the best performance.