Safflower model for simulation of growth and yield under various irrigation strategies, planting methods and nitrogen fertilization

Abstract

Development and use of crop growth models is an effective tool for agricultural planningand decision making in agricultural industry. Besides, the drought and limited supplies of waterin many areas of the world has increased attention to favourable strategies in farm managementsuch as efficient irrigation and planting methods. The objective of this study was to develop acrop model for safflower known as a multi-purpose crop under various irrigation regimes,planting methods and nitrogen fertilization. The experiment was designed as split-split plot thatarranged in randomized complete blocks with irrigation strategy as the main plot, plantingmethod as the subplot and nitrogen levels as the sub-subplot in three replications. The irrigationstrategies consisted of ordinary furrow irrigation (OFI) and variable alternate furrow irrigation(VAFI) as a partial root drying (PRD) technique. The planting methods were on-ridge planting(P1) and in-furrow planting (P2) methods. The fertilizer levels were 0 (N0), 100 (N1) and200 (N2) kg ha-1 of urea as 0, 46 and 92 kg N ha-1. Two years of the experiment carried out in asemi-arid area from 2012 to 2014. The field data of the second year of experiment were used todevelop the model and it was validated by the data of first year. The results indicated that theproposed safflower model is able to estimate evapotranspiration, soil water content, leaf areaindex, soil surface evaporation, crop transpiration, biomass, straw and seed yield of safflower inan appropriate manner. The safflower model is useful for having better field management andreducing administrative costs with respect to the model simplicity and its briefness in data input.