Six inbred lines of maize have been used (1- Syn-1, 2-MGW-3,3- S-165,4-Syn-22,5- Zm-9,6- M-17) entered in program were crossed in half diallel cross to produce 15 F1 cross in Field Crops Research Station of General Board Agricultural Research, Abu-Ghraib in fall season 2013. Seeds of genotypes (6 parents and 15 cross) have been planted in field of a farmer in Almusaib project in fall season 2014, using Randomized Complete Block Design (R.C.B.D.) with three replicates. The results
Have been analyzed according to method 2; model one of Griffing (6). The objective of this study was estimating of general and specific combining ability for parents, their hybrids, respectively, and some genetic parameters for growth, yield and its components characters. Results of statistics analysis showed that there were significant differences among genotypes for all studied characters. Results of genetic analysis showed that Mgca. In addition, Msca. Were highly significant in all studied characters and the σ2gca / σ2sca were less than one for all the studied characters. The effects of GCA were positive and negative among parents for all studied characters , the inbred line syn-1 was found as the best gca effect for ear height 6.122, leaf area 24.885cm2 300-kernel weight 3.499 gm and grain Yield 7.018, While the effect of SCA for single crosses were positive significant for all studied characters. The single cross hybrid (MGW-3×S-165) had highest SCA effect for 300-kernel weight 15.816 gm and the single cross (Syn-22× ZM-9) had highest SCA effect for ear length 2.697cm and for grain yield per plant 51.212 grain. The values of (σ2D) were more than that (σ2A) for all studied characters. The broad sense heritability was high between 85.55% for ear high and 99.39% for 300-kernal weight, while narrow sense heritability was low for all studied characters. The value of average degree of dominance was more than one for all studied characters.