This study was performed at Sakha Agricultural Research Station, Kafer El-Sheikh, Egypt, in 2014/2015 and 2015/2016 seasons under normal (five irrigation) and reduced irrigation (only one irrigation after planting one) regimes. Eighteen bread wheat genotypes were used to study the agronomic and morphophysiological characters and tolerance indices to distinguish wheat high yielding genotypes under reduced irrigation. The used genotypes were evaluated using randomized complete block design. The results revealed that reduced irrigation caused noticeable reduction in earliness, yield and yield components, harvest index and morpho-physiological in both growing seasons except 1000 kernels weight. Lines 3, 4 and 5 were the earliest ones for earliness characters and could be used in breeding program for earliness. It is obvious that lines 1 and 9 recorded the maximum values for most studied characters, especially, grain yield. Lines 1, 4, 6, 9, 10 and cultivar Misr 1, Giza 171 and shandweel1 had the highest relative water content and rate of water loss in both seasons. Also, Line 1 and Line 9 recorded the highest values for water use efficiency. Based on drought tolerance indices of mean productivity, geometric mean of productivity, stress tolerance index, yield index, harmonic mean and modified stress tolerance index, Line 1 and Line 9 were identified as suitable genotypes under well-watered and water deficit conditions. Misr 1, Misr 2, Giza 171, Lines 2, 6, 8, 10, 11, 12 and 13 were moderate for drought tolerance index and the others wheat genotypes were sensitive for water deficit.
