Combining Ability Variation of some White Maize Inbred Lines via Line X Tester Analysis under Ismailia and Mallawy Locations

Combining ability analysis was conducted using Line x tester analysis involves twelve new white inbred lines of maize were crossed two single crosses (S.C 128 and S.C 131) as testers during 2018 season. The resulted 24 hybrids with check hybrid T.W.C 324 were evaluated in two locations (Ismailia and Mallawy Research Station) during 2019 season. The combined analysis over the two locations showed highly significant due to crosses, inbred lines (L), testers (T) and line x tester interaction (L x T) for grain yield, indicating that there is a wide diversity among the studied lines in their contribution to the performance of crosses. Line and L x T were significant for all the studied traits, except ear length and no. of rows ear-¹. Mean squares due to crosses x location and lines x location interaction were significant for all the studied traits, except ear diameter and no. of rows ear-¹ of Lines x Location. Mean squares due to Lines x Testers x locations interaction were significant for all the studied traits. The results also showed that σ² GCA was larger than those obtained by σ² SCA for all the studied traits, except ear diameters. Showing that non-additive gene effects were more important component controlling the inheritance of these studied traits. Among 12 inbred lines used for study, the inbred ISM-8 showed good general combining ability with highly significant for grain yield. The best crosses ISM-3 x SC-128 and ISM-8 x SC-131 were having good specific combiners ability with highly significant for most of studied traits. These crosses ISM-3 x SC-128 and ISM-8 x SC-131 highly significantly out yielded to the T.W.C-324, suggesting the use of this cross in maize breeding programs.