The progress of seed development was accompanied change in pattern of biochemical and physiological parameter which affected by environmental condition and developmental stage during grain filling period. We performed several studies to understand the biochemical and physiological events taking place during seed grain filling. In this investigation, we studied changes in protein, monosaccharide and free proline content as biochemical parameter and fresh weight as a growth parameter during grain filling (8weeks) period at field growing Iranian wheat cultivar ( Triticum aestivum v. zarrin) . Results indicate that the most increase in fresh weight occurs between first and second week after anthesis. Constant phase of weight change occurred in 2, 3 and 4 week age. Significant decrease in fresh weight occurs in 5 week age of grain filling. Increase in protein content at 6 week age of grain may be related to biosynthesis of late-embryogenesis-abundant (LEA) proteins that thought to be involved in desiccation during dehydration phase of seed development in wheat grain not similar to stress condition.
