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 Gemmerza 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 all the studied traits, 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. 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% Silkrng towards (ear liness), 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 ( SC. 155, S.C. 3080 and S.C 3084) in yield potentiality ,while, The highest
mean performance were detected in the cross Gm. 1? x Gm.1021 (36.26 ard (fed)
followed by the cross Gm.31 x Gm.1004 (34.91 ard .l'fed) and the cross Gm 23 x Gm
1021 (33.99 ard lfed) , respectively. These crosses are favorable and could be used in
maize breeding programs.