Genetic Variability for the Yield and Yield-Related Traits in Some Maize (Zea mays L.) Inbred Lines in the Central Highland of Ethiopia

After rice and wheat, maize (Zea mays L.) is the third most significant and valuable crop in terms of industrial production in the world. The experiment was conducted to determine the nature and magnitude of genetic variability for various traits of maize inbred lines at the Ambo Plant Protection Research Center experimental field during 2013/2014, the major cropping season. The experiment’s design was described in 5 × 5 triple lattice designs. The results of the analysis of variance revealed that genotypic mean squares were significant for all traits, indicating that the inbred lines under study had a higher level of genetic diversity. In terms of genotypic and phenotypic variation, the largest coefficient was found in grain yield per hectare (28.49 and 35.43) followed by the number of tassel branches (23.14 and 24.92), respectively. Both days to 50% silking (91.57) and days to 50% tasseling (86.56) showed a high magnitude of broad-sense heritability. The results of the phenotypic and genotypic correlation analyses showed that grain yield per plant significantly correlated positively with five traits at both the phenotypic and genotypic levels. The number of kernels per row, aboveground biomass production per plant, harvest index, and grain yield per hectare might all be employed as selection criteria to increase the maize grain yield, according to path coefficient analysis at the phenotypic and genotypic levels. The grain yield and other significant yield components were found to be superior with inbred lines AMH169-55 and AMH169-86. Therefore, it is advised that these lines be used to further enhance the maize crop.