Diallel crossing and effects in yield components and grain yield for some corn Genotypes Zea Mays L


Eight inbred line of maize were crossed in a half-diallel mating system . The seeds of parents and F1 crosses were sown in fall and spring season using a randomized complete block design ( R.C.B.D) with four replications . The characters studied were : leaf area / cm2,number of ear/plant ,ear length, number of rows/ear ,number of grain /ear ,300 seed weight and yield of single plant .The parents( H5,R153,ZP607,W13R, JEEZA 5 ,JEEZA 275, SP18 , SP19 ) and these crosses showed a significantly for all characters except number of ear/plant , The parents were generally combined in desirable direction several characters except number of eras/plant for each seasons , ear length for fall season and number of grain / row for spring season .The dominance gene action was more effective than the additive gene action for all characters in the both season .The narrow – sense heritability values were ranged between 2.9% and 25.2%for number of grain / row and leaf area, respectively in the fall season, while in the spring season, ranged between 6% for number of grain /row and 15.4% for number of rows /ear and weight of 300 grain ( gm ) . The broad sense of heritability values were ranged between 72.2% and 95.3% for ear length and yield of single plant for the fall season, respectively While in the spring season they ranged between 73.9% and 97.3% for leaf area and yield of single plant , respectively .The average degree of dominance was higher than one for all characters . which revealed over dominance .