Genetic analysis of yield, yield-components and related phenological traits of maize (Zea mays L.) to breed under moisture stress conditions

Improved drought-tolerant maize hybrids would significantly reduce water consumption and increase yield in arid environments. Our knowledge about genetic parameters is very essential before starting a successful breeding program. The present research was carried out throughout three successive years between 2013-15 to reveal the pattern of inheritance in yield, yield-components and related phenological traits under moisture stress conditions. There was a positive and significant heterosis for grain yield/plant (GY), ear biomass/plant (EB), ear length (EL), grain number/row (GN) and plant height (pH). Inadequacy of additive-dominance model for the majority of the traits, indicate the role of epistatic in governing inheritance of those traits. There was a big-difference between dominance and additive effects for some traits, showing complete dominance and over dominance control the traits. Although dominance variation was greater than additive effect for phenological traits, however, the effect of additive effects was greater than dominance for GY, EB, ear-harvest index (EHI), row number/ear (RN) and ear-wood percent (EWP). Broad sense and narrow sense heritability ranged between 43.33-87.67 and 12.28-47.41, respectively. Meanwhile, the minimum gene number ranged between 1 to 6.53 in the studied traits. Due to the notable role of additive effects in governing the important traits of EB, EHI and RN, selection in early generations using the pedigree method for them, can be efficient to improve drought-tolerance and stabilize GY under moisture stress conditions.