Maize is an important crop in Ethiopia, but the average yield is low. This study looked at different maize lines to see which ones combined well and showed high yield potential. They found that some crosses, like L1 x L3 and L3 x L8, produced the highest grain yields. Certain lines, like L3 and L8, were good at passing on traits for high yield, while others were better for earliness. Overall, additive genes played a big role in controlling these traits. However, none of the crosses showed a significant increase in yield compared to the parents.