Two field experiments were carried out at the Agricultural Experimental Farm of Faculty of Agriculture;
Suez Canal University; Ismailia Governorate, Egypt during the two winter seasons (2012/13 and 2013/14). To study
effect of three irrigation regimes (full irrigation; skipping irrigation at tillering stage or heading stage), three rates of
nitrogen fertilization (50, 75 and 100 kg N/fed) and two wheat cultivars (Sakha 94 and Sids12) and their interactions on
yield and yield attributes. The experimental farm is located at Longitude 30o58\\ and Latitude at 32o23\\ at height of 13
meters above sea level. The texture of experimental site was sandy soil. Split–split plot design with three replications
was followed. The results showed that skipping irrigation at tillering or heading stage significantly reduction for studied
traits: plant height, no. of grains/spike, grain weight/plant, 1000 grain weight, grain yield, straw yield, and biological
yield during seasons with comparison to full irrigation regime. Crude protein content in wheat grains was significantly
increased by skipping irrigation than of full irrigation treatment. Increasing nitrogen level up to 100 kg significantly
increased all parameters except harvest index. Sakha 94 cultivar surpassed significantly Sids 12 cultivar in all studied
parameters. Calculations of water stress susceptibility index (S) shown that both wheat cultivars are sensitive to drought
stress conditions.