Two field experiments were carried out in newly cultivated sandy soil at New Salheyia Region, Sharkia Governorate in summer seasons of2010/ 2011 and 2011/2012 on seven barley cultivars to study partition and migration of Photosynthates in barley. Results can be summarized as follows: 1-There were significant differences between the seven barley cultivars Giza-124, Giza-125, Giza-126, Giza-129, Giza-130 and Giza-131 in growth characters, and yield and its components (except in crop index,

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... on coefficient and RPP veg). 2-Number of tillers, blades and spikes plant, dry wt. of tillers + sheats and blades/plant, blades area/plant, LAI for all cultivars tended to increase with advance days of plant age up to 100 days after sowing and thereafter decreased, meanwhile, plant height, flag leaf area, spikes dry wt./plant, main spike dry wt. tended to increase with advance plant age up to 115 days after sowing. 3-The seven barley cultivars differed significantly in photosynthate partition, where, significant differences were found in chemical components of vegetative organs, grains and straw, also, in glucose required for synthesis of the chemical components by the various barley cultivars organs, as well as, carbon equivalent for each one of carbohydrate and protein in vegetative organs, grains and straw and oil in grains. 4-There were significant differences between barley cultivars under study in yield energy per plant and /or per fed., where Giza-2000, Giza-129, Giza-130 and Giza-131 significantly outweighed the other three cultivars Giza-124, Giza-125 and Giza-126. 5-Highly significant and positive correlation coefficient were found between plant grain yield and No. of spikes/plant, spikes dry wt./plant, main spike dry wt., No. grains/main spike, main spike length, RPP gr , blades area/plant and flag leaf blade area, whereas. A negative and high significant relationship were found between grain yield/plant and plant height and main spike length. 6-Main spike dry wt., flag leaf blade area, No. of spikes/plant, blades area/plant, number of grains/main spike and spike dry wt./plant were the most affective in contributing to grain yield under this study. Generally, harvested grain yield of barley crop can be increased by growing Giza-2000, Giza-129, Giza-130 and Giza-131 where these four cultivars characterized by their highest values from vegetative growth, yield and its components and Photosynthates partitioning towards the economic yield compared with the other three cultivars under study Giza-124. Giza-125 and Giza-126. Also, from this investigate we can provide barley breeder with the most important characters in selection for high economic yield(i.e. main spike dry wt., flag leaf blade area, No. spikes/plant, blades area/plant, number of grains/main spike and spikes dry wt./plant).