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Heterosis and combining ability in yellow maize (Zea mays L.).
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Abstract: ABSTRACT: Fifteen new yellow inbred lines of maize were top crossed to three promising line testers, i.e. Gm. 1002, Gm.1004 and Gm. 1021 at Gemmeiza in 2004 season. The 45 top crosses plus three checks were evaluated at Gemmeiza and Mallawy Agricultural Research Stations in 2005 season. Significant differences were noticed between the two locations for the studied trait, except resistance to late wilt disease. Mean squares due to crosses and their partitioning lines and testers were highly significant, while, lines x testers interaction were significant for grain yield, resistance to late wilt disease under two locations and their combined, while, it was significant for combined of days to 50% silking. On the other hand, mean squares due to crosses x loc. were significant for grain yield and ear height, while mean squares of their partitioning L x loc were significant for grain yield, resistance to late wilt disease and ear height and mean squares of T x loc were highly significant for all the studied traits, while, the interaction of L x T x Loc. was not significant. The additive type of gene action was more important from non-additive type of gene action in the inheritance of all studied traits. The inbred lines Gm. 10, Gm. 14 and Gm. 22 exhibited positively and significant GCA effects for grain yield. Inbred lines Gm. 26, Gm.29 and Gm. 31 gave negative and desirable GCA effects for days to 50% Silking to wards (ear lines), Gm. 30 for plant height towards (shortness), Gm. 16 for ear height towards (low ear position) and the inbred lines Gm. 13 and Gm. 14 gave highly significant and desirable GCA effects for resistance to late wilt disease. The line tester 1002 gave significant and desirable GCA effect towards earliness, short plants and resistance to late wilt disease, while, the line tester Gm. 1021 gave positive and highly significant GCA effects for grain yield. At least, seventeen crosses surpassed from the three checks (S.C. 155, S.C. 3080 and S.C 3084) in yield potentiality, while the highest mean performance were detected in the cross Gm 17 x Gm1021 (36.26 ard/fad) followed by the cross Gm. 31 x 1004 (34.91 ard/fad) and the cross Gm 23 x Gm 1021 (33.99 ard/fad), respectively. These crosses are favorable and could be used in maize breeding programs.
Key words: Maize, Zea mays L., Line x tester, Combining ability, Gene action, Heterosis, Top crosses
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| Publication year |
2005
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| Pages |
4849-4860
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| Availability location |
معهد بحوث المحاصيل الحقلية - مركز البحوث الزراعية - ش الجامعه – الجيزة
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| Availability number |
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| Organization Name |
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| serial title |
J. Agric. Sci. Mansoura.Univ., 31(8): 4849-4860
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| Author(s) from ARC |
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| Agris Categories |
Agricultural research
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| Publication Type |
Journal
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