Journal of Crop Production and Processing

  To predict growth and yield, it is needed to study sub-models of phenology, dry matter production and partitioning, leaf area variations and soil water balance. In the present study, for predicting yield of maize under Isfahan conditions, parameters of the sub-models in the aforementioned model were estimated using data of planting dates between 1988 and 2004 in Isfahan region and data of other researchers in different regions of the world. Daily variations of phenology, dry matter, leaf area and soil water balance were estimated using growth and yield model by daily climatic data (minimum temperature, maximum temperature, radiation and precipitation) and then final yield was predicted at the end of the growing season. Observed yields were between 11370 and 15770 kg/ha, with average yield of 13130 kg/ha while the predicted yields were ranged between 12440 and 15440 kg/ha, with average yield 13360 kg/ha. Evaluation of the model showed no significant difference (confidence limits of 95%) between regression coefficients of observed and predicted yields ( a = 3233 ± 1380 and b = 0.77 ± 0.12 ) and coefficients of 1:1 line ( a = 0 and b = 1). The R² value of the model was 0.92. In addition, values of root mean squared deviations and coefficient of variation were 570 kg/ha and 4.3%, respectively. Therefore, it was concluded that this model has suitable precision for predicting maize yield under Isfahan conditions.