Exploitation of rice heterosis under Egyptian conditions [electronic resource].

Includes references.

Studies of heterosis and combining ability of ten cytoplasmic genic male sterile lines and five Egyptian testers (restorer) were estimated using line x tester analysis for some agronomic characters and yield and its components to get useful information for hybrid rice program in Egypt. Hybrids with a yield advantage of >1.5 t/ha over the highest yielding check variety, Giza 178R were considered as promising. Among 50 hybrid combinations evaluated, 15 were most promising with mean performance of grain yield ranging from 12.491 t/ha for IR 69625N Giza 182R (SK 2058H) to 13.920 t/ha for IR70368N Giza 181R (SK 2047H) with an average of 13.384 t/ha. The yield values over the best local inbred check, Giza 178R ranged from 1.999 to 3.428 t/ha. with an average of 2.792 t/ha. Mean standard heterosis estimates ranged from 19.1% to 32.7% with the average of 26.6%. Al110ng the ten cytoplasmic male sterile (CMS) lines, IR 68899 A, G46 A,IR 58025 A, and IRA69625 A were the best general combiners for grain yield. The restorers, Giza 178 R and Giza 181 R were the best general combiners among testers for grain yield and most studied characters. From the breeding point of view, some crosses were identified to be the best ones for recombination breeding, among them were the crosses IR 68888 A / Giza 178 R (for earliness), IR 68885 A / Giza 178 R (for short stature), IR 68885 A / GZ 5121 R (for productive tillers planr1), IR 58025A / Giza 178 R (for panicle weight, filled grains panicle-1, spikelets panicle-1, and grain yield) and IR 70368 A / Giza 181 R (for 1000-grain weight and spikelet fertility).

Summary in Arabic.

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