Drought is one of the major environmental factors which threaten wheat production worldwide. Nine bread wheat genotypes were crossed in a 9x9 half diallel scheme in 2012/2013. The nine parents Yakora (P1), Sakha 93 (P2), Misr 2 (P3), Sids12 (P4), Gemmiza 11 (P5), Line 150 (P6), Line 116 (P7), Line 145 (P8) and Line 124 (P9) and their thirty-six F1 crosses were evaluated under normal and stress conditions during 2013/2014 in two experiments in a randomized complete block design (RCBD) with three replications at the Experiment Research Station of Moshtohor, Benha University, Kalubia Governorate, Egypt. The results of analysis of variance showed significant for all studied traits. Mean squares for genotypes, parents, crosses and parents vs. crosses were significant for all traits except days to heading for parent's mean squares. The highest mean values were detected under combined analysis by parents P5, P7,P1,P4,P4 and p8 for days to heading, plant height, no. of spike/plant, 1000 grain weight, no. of kernels/spike and grain yield, respectively. While, the highest mean values were recorded under combined analysis with crosses P1×P7, P3×P7, P1×P3, P5×P8, P4×P9 and P4×P5 for days to heading, plant height, no. of spike/plant, 1000 grain weight, no. of kernels/spike and grain yield, respectively. Mean squares of both general (GCA) and specific (SCA) combining ability estimates were highly significant for all the studied traits. The ratio of GCA/SCA being more than unity in all cases indicated that the additive gene effects were more important for all of the traits. P8 was a good combiner for days to heading and grain yield. The highest desirable SCA effects were obtained with P6×P8 for days to heading, P1×P4 for plant height and 1000 grain weight, P1×P5 for no. of spike/plant, P1×P3 for no. of kernels/spike, P1×P7 for grain yield under combined analyses. P4 was high tolerant for stress irrigation, for grain yield. The cross P2×P4 had high tolerance to stress irrigation treatment for this trait. |
