Performance and Combining Ability for Yield and its Components in Some Single Crosses of Maize (Zea mays L.) Developed in Syria

Fifteen single crosses were produced by using half diallel fashion in 2008, and they were evaluated in 2009 season at the Agriculture Scientific Research Center in Homs, Syria. Mean performance and general and specific combining ability were estimated for Grain Yield/Plant (GYP), Ear Length (EL), Ear Diameter (ED), Number of Rows per Ear (NOR) and Number Of Kernels per row (NOK). Hybrids mean squares were significant for all traits. Both additive and non-additive genetic effects were involved in the inheritance of most traits. Additive genetic variance was predominant in the inheritance of all studied traits. The parental inbred lines P1 (IL.366-06) seemed to be the best combiner for grain yield plant-1. The highest desirable SCA effects were recorded in the crosses (IL. 791-06 × IL.332-06), (IL. 366-06 × IL. 271-06), (IL. 271-06 × IL.75-06) for grain yield plant-1.