الفهرس 
Introduction
Mean performance of traitsOnly 14 pages are availabe for public view
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Abstract
A full diallel set of crosses among six inbred lines of maize were evaluated under two planting dates for grain yield and flowering , vegetative traits and yield components traits at Gemmeiza Maize Research Dept., (Developed Improvement of Maize by Industrial Genotype Project), Field Crop Research Institute, ARC, Obtained results are as follows:
1-Highly significant variances due to general and specific combining ability for all studied traits, except days to 50% tasseling , days to 50% silking , ear length , ear diameter , no. of row /ear and 100 kernels weight for (GCA)and days to 50% silking, ear diameter and no. of row /ear for (SCA). These results indicated that both additive and non additive types of gene effects were involved in the inheritance of these traits.
2-The ratio of GCA/SCA was less than unity for all studied traits except for days to 50% tasseling in date two resistance to late wilt disease and ear diameter in date one.
3-GCA effects showed that the best general combiners for increasing grain yield were P1and P6 inbred could be considered as the best general combiner for thickness of ears
4-SCA effects showed that the best F1 cross combinations, Crosses (P1×P4),(P1×P5),(P2×P5), (P2×P6),(P3×P5), (P3×P6), (P4×P2), (P3×P2) and (P4×P6) had highly significant effect (SCA)for grain yield and most of traits studied relative to its reciprocal parents , respectively.
5- Highest positive significant heterosis effect over better-parents and mid-parents were recorded all crosses had highly positively significant heterosis effect for grain yield (ard/fed) and ten crosses had negative significant and highly significant over check variety.
6-General (δ2gca) and specific (δ2sca) combining ability and their interaction with dates showed that (δ2gca) was higher than (δ2sca) for all studied traits except ear position and ear length this indicated the additive gene action was more importance in inheritance of all studied traits .
7-At combined data was highly positively and significant correlated with plant height and positively and significantly correlated with ear diameter, ear height and ear length but the correlation was negatively and significantly with late wilt.