development a regression relationship between rainfed wheat yield and soil properties in a semiarid region, zanjan province

rainfed wheat is the main source of staple food for people in the developing countries. various factors contribute to and affect the production of this crop. the aim followed in the present study was to develop a model to estimate rainfed wheat grain yield as based on physico-chemical properties of the soil. therefore, wheat grain yield and soil physico-chemical properties were separately determined in triplicates at 53 rainfed wheat fields throughout zanjan province in growing season. year 2014 making use of partial least square regression, a model was developed to explain the relationship between rainfed wheat grain yield vs soil properties (n=40, r2= 0.6). silt and calcium carbonate equivalent were the most effective soil properties affecting the crop's grain yield, with the standardized coefficients of the estimating model equal to 0.23 and -0.24, respectively. the results of the research revealed that some soil physico-chemical properties including silt, calcium carbonate and potassium, in order of priority, affected most the rainfed wheat grain yield.