Analyzing Wheat Yield Constraints in Parsabad Moghan, North-West of Iran

One of the main problems in crop production in Iran is the difference between actual yield and attainable yield which is called yield gap. Thus, identifying yield constraints and yield gap are important. Therefore, a study was conducted in 60 farms in Parsabad Moghan, during 2013-14 and 2014-15 crop years using Comparative Performance Analysis (CPA). In this study, several attributes related to management operations and crop characteristics were recorded and measured. Then, the relationship between different variables and grain yield were considered, using stepwise regression. The results showed that there is a 2317.42 kg/ha difference (gap) between actual yield (average farmers' yield) and attainable yield (maximum farmers' yield). It was identified that planting time, spike density, the number of vents of split application of urea, the number of land preparation operations, farming experience and repeated use of fungicides with contributions of about 18, 29.7, 20, 4.6, 14.3 , and 13.4 percent, respectively, were responsible for this yield gap. Further analysis of the data revealed that most of the variables listed above can be controlled by the agronomic management. It was concluded that with proper farm management and considering the listed yield gap factors, it would be possible to obtain higher grain yields of about 2316 kg/ha in the irrigated wheat farms, compared to the current average farmers’ yield.