Estimation of heterosis , Combining ability and heritability for six inbred lines and single crosses by using half diallel in corn (Zea mays L.).


Six inbred lines of maize ( (1)HS ,(2) ZM7, (3)OH40 ,(4) W13R ,(5) DK , and (6) IK8 ) were used in this study using half diallel cross analysis , These parents were planted in spring season of 2012 to produce fifteen F1 single crosses. In autumn season of 2012 the parents and crosses were planted using R. C. B. D. with three replicates to determine the heterosis , combining ability , Heritability and expeeted genetic advance . Data were collected for plant height, ear length, number of rows per ear, number of grains per row, 300 grains weight and grain yield per plant. Data analyzed statistically to study the effects of general and specific combining abilities and genetic parameters for studied traits , The results showed that the mean square of genotypes ,general and specific combining ability, were highly significant for all characters. The hybrid (Zm7×OH40) gave the highest ear length (20.12 cm )and grain yield per plant (285.2 gm). The (Zm7×OH40) gave the highest heterosis in grain yield per plant(92.54%) .The cross (HS×IK8) gave a good specific combiner for all characters except grain weight .The additive gene action was more important from dominance gene action .The broad sense heritability ranged from (21.17%) for number of grain per row to (91.7 %) for ear length .The narrow sense heritability ranged from (5.75%) for number of grain per row to (88.71%) for ear length .The expected genetic advance from selection was middle for ear length (23.11%) and high for number of rows per ear (34.41%) while were low for other studied characters .