ESTIMATION OF OIL AND PROTEIN PERCENTAGE IN DIALLEL AND RECIPROCAL HYBRIDS OF MAIZE

A full diallel crossing system was performed among four inbred lines of maize namely 1 - OH40 2-IK58 3-Ly55 4- HS on field of Al-Madain in the centere of Baghdad(Iraq) in spring and autumn season(2006-2007) a comparison the objective was estimation of several genetic parameters for oil and protein content in maize. Sowing these genotypes in randomized complete block design with four replications.Significant differences were found among genotypes for oil and protein content.The results showed that the diallel hybrids(1x2) (3x4) produced higher oil percentage(4.6)%,while reciprocal hybrid(2x1) produced higher oil percentage (4.7)%.The diallel hybrid (1x3) produoced higher protein percentage(10.1)%,while reciprocal hybrids(2x1),(3x2) produced higher protein percentage (9.6)%.The higher positive hybrid vigour percentage for best parents for oil percentage (16.1 )%for diallel hybrid (2x3), and(18.4)% for reciprocal hybrid (2 x 1). The higher positive hybrid vigour percentage for protein percentage (29.9)% for diallel hybrid (2x3) and (36.5)for reciprocal hybrid (3x1). No significant differences in GCA and SCA in the other characters oil and protein. The average degree of dominance ( ā ) was less than one for diallel hybrids for oil and protein percentage.The average degree of dominance( ā )for reciprocal hybrid was less than one for protein percentage while more than one for oil percentage (1.5).The heritability percentage was low for broad and narrow sense for oil and protein percentage for diallel hybrids and reciprocal hybrids.Genetic variance dominance values б²D and genetic variance additive values б²A was low for characters for diallel hybrids and reciprocal hybrids.