increased nitrogen applications to crops influence plant-herbivore interactions and potentially increase herbivore population growth.in this research, the impact of nitrogen fertilizations on nutritional quality of three canola (brassica napus l.) cultivars (zarfam, okapi and modena), and, consequently, the performance of mustard aphids, lipaphis erysimi kalt., on them were investigated under g...

nitrogen is produced mainly from its most abundant source, the air, using three processes: membrane, pressure swing adsorption (psa) and cryogenic. the most common method for evaluating a process is using the selection diagrams based on feasibility studies. since the selection diagrams are presented by different companies, they are biased, and provide unsimilar and even controversial results. i...

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. to do this, a study was conducted in 95 farms gorgan of in five villages, during two years 2007 and 2008. in this study, all of the information about management operations, soil and crop charac...