Fourteen inbred lines were top-crossed to three testers, i.e. SK-7001/8,
SCSK-17 and Gz-2 at Sakha in 2002 season. The top-crosses were evaluated in
2003 at Sakha and Gemmeiza locations. Significant differences were detected
between two locations for all the studied traits. Mean squares of crosses and their
partitioning into lines and testers were significant for all studied traits except for ear
diameter for lines and testers. Moreover, mean squares due to lines x testers
interaction were highly significant for grain yield, plant height. While, it was significant
for ear length, ear height and weight of 1 ~O-grains. The best desirable GCA effects for grain and most yield components were
obtained by inbred lines SK-63-32 and SK-58-30. Also, the inbred lines SK-62-11, SK-
62-12 and Sk-62-13 showed the best GCA effects for silking date, plant and ear
height towards earliness and short plants, respectively. The inbred tester SK-7001/8
showed the best desirable GCA effects for number of rows/ear. Moreover, the tester SCSK-17 was the best combiner for grain yield and
number of kernels/row. While, the tester Gz-2 was the best general combiner for
earliness and short plants. Two top crosses SK-63-32 x SK-7001/8 and SK-63-32 x
SCSK-17 did not differ significantly from the check variety SC1O. Moreover, fourteen
top crosses exhibited significant differences than check variety TWC310. Also, most
of the remainder top crosses did not differ significantly from the last check (fWC 310).
These crosses can be used in maize breeding program. The additive genetic variance was more important for grain yield, weight of
1 DO-grain, plant height and ear height. While, non-additive genetic variance was an
important for number of kernels/row, ear diameter and silking date. Moreover, non-
additive genetic variance was more affected interacted by locations than additive
genetic variance for all studied traits except number of kernelslrow and ear diameter.