ESTIMATHON OF COMBINING ABILITY AND GENE ACTION USING THE HALF DIALLEL CROSSE IN MAIZE

Abstract

Half diallel cross was carried out among six inbred lines of maize in spring season (2004), autumn season (2004) acomparison experiment was carried.The experiment was designed according to (R.C.B.D.) with three replications to determine general and specific compining ability effects and gene action. Significant differences were found among parental and their crosses for all characters. The parents were generally combined in desirable direction for several characters. Variance of genral and specific combining abilities were significantly different for all than characters. The highest Sca effects were expressed in HS × W17 for grain yield. Dominance genetic variance was higher the additive genetic variance for all characters. The broad – sense heritability values were ranged between (33.33%) for ear diameter to (91.3%) for grain yield / plant while narrow – sense heritability value were ranged between (10.34%) for grain yield/plant to (33%) for leaf area. The average degree of dominance was higher than one for all the characters which revealed the over - dominance.