Estimation Genetic Action of Heritability Percentage and Inbreeding Depression of Four Hybrids Maize by Generation Mean Analysis (Field Traits)

Abstract

With the aim of current study to estimate genetic action, heritability percentage in its broad and narrow sense and inbreeding depression resulting from inbreeding, using the generation mean analysis method to analyze the generation's means of hybrids maize that different in flowering dates and maturity. The genetic action, that controls inheritance of the field traits to the selected inbred lines and their resulting hybrids using the generation mean analysis. Five pure inbred lines of maize (ZA17WR, Zi17WZ, ZM74, ZM19 and ZM49W3E) were selected from fifteen different inbred lines with flowering dates and maturity in the spring season 2019 and were crosses according to the research target (late × late),( late ×early) ,(early ×late) and( early ×early). On 2019 fall season were entered into a backcross program to analyze the means generation analysis. On 2020 spring season to produce the (six generations) which are (P1, P2, F1, F2, BC1 and BC2) for the four crosses were evaluated in comparative experiments using a randomized complete block design (RCBD) and with three replicates. Genetic analysis was done for the components of genetic variance for the three criteria, according to [1] for the traits of the number of days to 75% tasselling, Number of days to 75% silking, plant height , ear, leaves area and yield of individual plant. Results showedThe dominance gene action is dominant in the inheritance of the silking and tassling traits in the four crosses. As for the trait of the number of leaves and the yield of the plant, the dominance gene action controlling its inheritance was in the first hybrid and the additive gene action in the second, third and fourth crosses, while the dominance action had the greatest contribution to the inheritance of the trait The area of leaves in hybrids 2, 3 and 4 and in the first hybrid was the largest additive gene action contribution, The percentages of heritability in the broad and narrow sense differed among the four hybrids for the traits studied. The highest percentage of heritability in the narrow sense for the trait of plant yield in the fourth hybrid was 91.50% due to the high additive variance, while the highest percentage of heritability in the broad sense was for the trait of leaf area in the third hybrid was 99.27%The highest percentage of genetic improvement for the trait of the number of leaves in the fourth cross was 27.64% , and the highest Inbreeding Depression for second generation F2 for yield in the same hybrid was 22.66%,