Genetical studies on barley productivity in relation to leaf rust infection [electronic resource].

Includes references.

The present experiment was carried out at Sakha Agricultural Research Station during the three successive seasons 2007/08, 2008/09 and 2009/010, to find out the type of gene action using the six populations (Pi, P2 , F1 , F2, BC 1 and BC2) of five crosses of barley; cross 1 (Giza 123xGiza 2000); cross 2 (Giza 123x Line-2); cross 3 (Rihane-03xline-1), cross 4 (Rihane-03xline-2) and cross 5 (Giza 2000xline-2) and their six populations grown under normal conditions. Grain yield and its components and some growth attributes and resistance to leaf rust disease were investigated. Results indicated the presence of non-allelic interaction for most studied traits in all crosses under study. Also, the relative importance of additive and dominance effects varied among traits and crosses. Regarding the epistatic components, the dominancexdominance effect was greater in magnitude in most studied traits. Positive heterotic effects relative to the mid-parent and better parent were found for most of the studied traits. Heritability estimates in broad sense were relatively high for all studied traits in all crosses, but narrow sense estimates were low to high for all studied traits in all crosses. The expected genetic advance as percent of F2 ranged from low to high in all crosses for all traits. Results also indicated the possibility of practicing selection in early generations to obtain highyielding genotypes. Generally, crosses 1 and 3 for grain yield and crosses 1 and 5 for leaf rust resistance were higher in magnitude with high genetic advance associated with high heritability .and could be promising in barley breeding program. Keywords: Rordeum vulgare L., gene effects, heritability, genetic advance, heterosis, Puccinia hordei

Summary in Arabic.

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