Diallel Analysis of Seven Maize Inbred Lines for Different Characters across Locations

Seven elite yellow maize inbred lines derived from different genetic sources were evaluated in this study to estimate combining ability, type of gene action, and superiority crosses over commercial check hybrids. In 2021 growing season, all possible combinations between these inbred lines were done, excluding reciprocals (Griffing's 1956, method 4, model 1) at Gemmeiza Agricultural Research Station, located in the center of the delta, Gharbia governorate, Egypt. In 2022 season, the resulting 21 crosses along with two commercial crosses; SC. 168 and Pioneer SC. 3444 were evaluated in a randomized complete block design (RCBD) with three replications at the three Research Stations (Locations); Gemmeiza, Mallawi and Nubaria. Recorded data were days to 50% silking, plant height, ear height and grain yield. The results showed significant differences for all the studied traits between the three locations. Mean squares of crosses and their partitions, GCA and SCA were highly significant for all studied traits, meaning that both additive and non-additive gene effects were important in the inheritance of all studied traits, however the additive gene effects played the major role in the inheritance of days to 50% silking, ear height, and grain yield, meanwhile, the non-additive gene effects were predominance for the inheritance of plant height. The parental lines Gm 6022, Gm 36 and Gz 639 had significant GCA effects for grain yield. Seven crosses (Gm 5 x Gm 36), (Gm 5 x Gz 639), (Gm 6052 x Gm 74), (Gm 6022 x Gm 15), (Gm 74 x Gm 36), (Gm 15 x Gm 10) and (Gm 10 x Gz 639) showed significant values for SCA effects for grain yield. Cross Gm 6052 x Gm 74 significantly out yielded (34.23 ard/fed) the best check SC 168 (30.87 ard/fed) and is recommended for further evaluation to be registered as new hybrid.