Corn Yield Estimation Using Agro climatic Indices in West and Southwest Regions of Iran

Crop yield estimation can be helpful for planning and implementation of policies pertaining to food procurement, distribution, pricing and import-export. Since crop yield is the culmination of many temporal plant processes and is affected by various climatic factors, parameterization of these factors and investigation of their relationship with yield are essential for crop yield modeling. In this study, the feasibility of corn yield estimation has been carried out using statistical regression models together with the analysis of correlation between corn yield during different growth stages and climatological variables for some regions in the west and south west of country. The results revealed that the difference between estimated and actual corn yield were -250 to -3577 and 16 to 1812, -160 to -3000 and 24 to 2566, -270 to -1370 and 286 to 3550, -188 to -1322 and 26 to 2130 kg/ha for Kermanshah, Kohdasht in Lorestan, Dehloran in Ilam and Dezfool in Khozestan, respectively.In Overall, the results show that maximum and minimum temperatures, wind speed at 2 meter height, sunshine hours and relative humidity have maximum correlation with corn yield in emergence of earing to silking and silking to physiological maturity (ripening) stages which had close estimated values to observed ones for different regions(correlation coefficient of 0.573 to 0.858 and standard error of 1002 to 2148 kilgram per hectare).