Abstract— A half-diallel cross among six maize inbred lines was carried out in 2023 at the Maize Research Department, General Authority for Scientific Agricultural Research. In 2024, fifteen hybrids, the control variety Ghouta 82, and the parental lines were evaluated to estimate general and specific combining ability and heterosis for ear height, ear length, ear diameter, and number of rows per ear. Significant differences were observed among lines and hybrids for all traits. The hybrid (P6 × P4) exceeded Ghouta 82 in ear height, while all hybrids surpassed it in ear length, ear diameter, and number of rows per ear. Except for (P5 × P2), all hybrids showed positive heterosis, and nine exhibited significant heterosis compared to the best parent in row number. Ear height was mainly controlled by additive gene effects, while both additive and non-additive effects influenced the remaining traits, with additive effects predominating.
Al-Najjar et al. (Sat,) studied this question.