A half diallel set of crosses involving six parents i.e. Bani Sewef-1, 2 and 3; Sohag 1, 2 and 3 were evaluated under three sprinkler irrigation every 4, 8 and 12 days in three separate experiments. In each experiment, the parental varieties and their possible crosses were arranged in a randomized complete block design with three replications. Irrigation mean squares were significant for all the studied traits. The effect of sprinkler irrigation every 8 days increased significantly yield and some of its components. While, the effect of sprinkler irrigation every 4 days had the highest value for quality characters. Mean squares for genotypes, parents and Fl hybrids were significant for all studied traits except parent mean squares for number of spikes and semolina percentage. The cross P4 x P5 had the highest grain and biological yields per plant, but without significant superiority over the two crosses P2 xP5 and P3x P4. The cross P2 x P3 gave the highest values for dry and wet gluten percentages. Mean squares for parents vs. crosses were significant for all traits except straw yield and semolina percentage. Fl means were significantly higher than parental mean for most traits.
The variance associated with general and specific combining abilities were significant for all studied traits. Grain yield and wet gluten percentage exhibited low GCA/SCA ratio which is less than unity. While the magnitude of additive and non-additive types of gene action were similar for plant height. On the other hand, high GCA/SCA ratio, which exceeded the unity was detected for other traits. The mean squares of interaction between both types of combining ability and irrigation treatments were significant for all studied traits, indicating that both additive and non-additive types of gene action varied from irrigation treatment to another. The parent P2 for dry gluten, P3, P6 and Ps for protein percentage, and 1000-kernel weight, P4for peduncle length, number of spikes, straw and biological yields, and P6 for grain yield and some of yield components seemed to be the best general combinrs.
The most desirable SCA effects were detected by crosses PI x P4 and P3 x P4 for peduncle length, pi x P5 for short plant, P4 x P5 for number of kernels/spike, P3 x P6 and P4 x P5 for 1000-kernel weight, P, x P3, p! x P4, P2 x P4 and P6 x P6 for straw yield, P, x P4, P2 x P5, P4 x P6, P3 x P4, P3 x Pfi and P4 x P6 for grain yield/plant, PA x P4, P2 x P3 and P5 x P6 for biological yield, P, x P6, pi x P61 P3 x PG and P4 x P6 for semolina percentage, P2 x P3 and P5x Ps for dry gluten percentage and P2 x ps and P4 x P6 for wet gluten.
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