Combining ability for yield and some agronomic traits in five maize populations and their crosses under normal irrigation and drought stress [electronic resource].

Includes references.

Five maize populations were used to create a complete diallel. The resnlted 20 direct F1•s and their reciprocals in addition to the five parental populations were evaluated under normal irrigation and drought stress at Nubaria and Sids Agric. Res. Stations. Results indicated that both GCA and SCA mean squares were significant for yield, days to 50 % tasselling and silking, and number of ears/plant under both irrigation regimes, while GCA mean squares for plant and ear height were significant only under normal irrigation. The magnitude of GCA mean squares was considerably higher than that of SCA indicating that additive gene effects play an important role in the inheritance of those traits. Giza-2 C8 and DTP.l C7 populations revealed significant positive GCA effects for grain yield and number of ears/plant and negative GCA effects for plant and ear height and number of days to 50% tasselling and silking. Tep.5, AED, and Laposta populations exhibited significant negative GCA effects for yield and number of ears/plant, while they had significant positive GCA effects for the other traits. Results indicated that Giza 2 C8 and DTP.I C7 populations are good combiners and they can be considered as good sources for developing drought tolerant inbred lines. Most of the population crosses displayed significant positive SCA effects for grain yield under either one or both irrigation regimes.

Summary in Arabic.

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