An experiment was conducted during the three successive growing seasons, 2017/2018, 2018/2019 and 2019/2020 at El-Gemmeiza, Agricultural Research Station, Agricultural Research Center, Egypt, to study the relative merits of pedigree selection under favorable and low input conditions (low nitrogen and water). Three cycles of pedigree selection for high grain yield were achieved under both conditions. The base population was the F2-population of the cross Sakha 94× Sids13. In the F5 generation, the selected families under favorable and low input conditions were evaluated at both environments. The phenotypic of variability for grain yield/plant in the F2 generation was very high and accounted to 39.48% with a range of 10.18 to 58.13% under favorable conditions, while under low input conditions reached to 30.53% with a range from 10.01 to 44.76%. The genotypic variance was slightly less than the phenotypic variance under both conditions and generally decreased from the base population (F2) to F5-generation. Broad- sense heritability estimates for grain yield plant under favorable and low inputs conditions were 86.13 and 67.50% after three cycles of selection, respectively. Realized heritability under favorable conditions was (43.81, 54.69 and 72.32%) compared to (41.58, 48.73 and 60.45%) under low input conditions for cycles 1, 2 and 3, respectively. The average observed gain from selection under favorable conditions, that was evaluated under both conditions, showed significant increase in grain yield from the bulk sample by 21.89 and 43.37%, and from the better parent by 32.20 and 46.82 %, respectively. Selected families for grain yield under low input conditions that was evaluated under both conditions showed a significant increase in grain yield from the bulk sample by 16.12 and 32.21 % and from the better parent by 19.27 and 33.66 %, under favorable and low input conditions, respectively. Results revealed that the antagonistic selection reduced sensitivity to low input stress, and synergistic selection increased it. Moreover, selection for grain yield/plant under low input stress was better than under favorable conditions.