Genetic analysis by generation mean analysis and using mixed models method in maize (Zea mays L.) genotypes under water deficit stress condition

Investigation of inheritance of agronomic traits, type of genes action and selection of appropriate breeding method is of great importance in order to achieve the maximum potential of breeding genotypes. In order to estimate the genetic components of important morphological traits were using generation mean analysis with mixed models in four basic generations (BC1, F2, F1, and BC2) resulting from crossing of maize inbred lines MO17 (drought tolerant) and B73 (drought sensitive), under water deficit stress factor at three levels of including well-watered, intermediate, and severe water deficit stress in field conditions were studied in the growing season in 2016 and 2017. The results of this research showed that the highest heterosis of F1 was observed in the well-watered for one grain weight (112%), in the intermediate stress for grain yield (59%), and in the severe stress for anthesis silking interval (59%). Average degree of dominance in well-watered for 100 grain weight trait, in intermediate stress for number of ears per plant and in severe stress for plant height and number of leaves per plant were positive and greater than one. Also, in three irrigation conditions, due to the greater dominance gene effects (dominance gene effects was obtained for grain yield in plant in well-watered condition 75, intermediate stress 115, and severe stress 63) and variance of dominance gene effects in genetic control of grain yield and important traits, the production of hybrid varieties is essential to exploit these effects.