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Direct and indirect selection for grain yield through 1000grain weight, spikelet fertility and spike density were achieved in bread wheat at the Exper. Farm Fac. Agric., Minia Univ. Egypt during the three successive seasons of 2016/17 to 2018/19. After two cycles of pedigree selection phenotypic variation of grain yield/plant, 1000grain weight, spikelet fertility and spike density decreased rapidly from F2 base population to F4. Indirect selection through high 1000 grain weight resulted in the highest grain yield/plant (23.62g) followed by direct selection for grain yield/plant (20.66 g). Average direct gain for the ten selected families of direct selection for grain yield showed highly significant increase in percentage of the bulk sample of 62.95% and the better parent of 39.25%. Pedigree selection was effective in detecting the high yielding families. Family No. 145 gave significant (P≤0.01) grain yield in percentage of the better parent and bulk sample by 77.09 and 107.23%, respectively. Average direct response in percentage of the bulk sample was significant and reached 21.08% for 1000 grain weight, 31.12% for spikelet fertility and 7.27% for spike density. Three families; No. 15, No. 72 and No. 153 surpassed significantly the bulk sample by 33.83, 43.01 and 29.28%, respectively, when selection practiced for 1000 grain weight. Family No. 145 considered to be a promising line in grain yield and spikelet fertility. High strong positive genotypic correlation was found between grain yield with each of weight of spikes/plant (0.81), no. of grains/spike(0.71), weight of grains/spike (0.91), 1000grain weight(0.92) and spikelet fertility(0.70).

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Fifty S1, S2 and S3 white maize lines were extracted and developed from five open different populations for searching of new maize inbreds that tolerate drought accompanied with distinct performance as heterotic groups. These lines were evaluated along to ten drought tolerant inbred lines of Maize Section (ARC) under field conditions of normal and stress watering regimes during 2017, 2018 and 2019 seasons, respectively. Anthesis-silking interval (ASI), 100-Kernel weight (K.I), grain yield per plant (GYP) and stress tolerance index (STI) were studied. Watering regimes (W.R) combined across each inbred generation are highly significant source of variation for ASI, KI and GYP. Inbred lines of the three generations varied highly significantly under both watering regimes for K.I, GYP and STI. However, for ASI only all S1's varied significantly under normal irrigation, but S3's are highly significant in both irrigation trials. The S2 and S3 showed somewhat significantly higher reduction for K.I due to drought stress in all groups of inbreds except those of C.1 and ARC. All the groups of inbred lines of the three generations recorded significantly about 8-14% ratios of GYP depression due to drought. The estimates of STI in S1 and S3 over parental origins were higher (1.47 and 1.35) than obtained by S2 (0.88).The developed maize inbreds exhibited desirable performance accompanied with reliable drought tolerance and sufficient variation that offers further responses to upgrading. The validity of obtained inbreds for rolling in maize hybrids programs will be accomplished by assessing the combining abilities as different heterotic groups.