Selection efficiency under both normal irrigation and water deficit conditions in durum wheat [electronic resource].

Includes references.

The present research was carried out to study the efficiency of pedigree selection in improving grain yield under normal irrigation and deficit irrigation conditions. Three cycles of selection were completed under each environment on the F2 to F5-generations. At the last season the selected families under each environment were evaluated under both environments. The genotypic variance was slightly less than the phenotypic variance under both environments and generally decreased from the base population (F2) to F5-generation. Broad sense heritability estimates for grain yield planf1 under normal and deficit irrigation conditions were 93.3 and 90.8% after three cycles of selection, respectively. The realized heritability under normal irrigation was 10.9, 23.2 and 52.8% compared to 9.8, 31.3 and 36.9% under deficit irrigation conditions for cycles 1, 2 and 3, respectively. The average observed yield gain from selection under normal irrigation and evaluated under both environments showed significant difference in grain yield from the bulk sample by 9.3 and 26.3%, and from the better parent by 9.9 and 10.2%, respectively. Selected families for grain yield under deficit irrigation and evaluated under both environments showed significant difference in grain yield from the bulk sample by 4.6 and r 7.7%, and from the better parent by 4.1 and 11.3%, under normal and deficit irrigation, respectively. Drought susceptibility index (OSI) ranged from 0.01 to 3.13 for the families selected under normal irrigation, and from 0.09 to 2.36 for' the families selected under deficit irrigation. Results indicated that the antagonistic selection increased sensitivity to deficit irrigation, while the synergistic selection decreased it. Selection for grain yield planf1 under normal irrigation (synergistic selection) was better than under deficit irrigation (antagonistic selection). Keywords: Triticum turgidum var. durum, synergistic and antagonistic selection, realized heritability

Summary in Arabic.

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