Characterization of Selected Maize Inbred Lines Adapted to Highland Agro-Ecologies of Ethiopia Using Morphological and Molecular Genetic Distances

Characterization of available genetic diversity is a crucial step in effective crop improvement which provide basis for the analysis of combining ability and exploitation of heterosis of inbred lines in hybrid breeding. Characterization involves evaluation of quantitative and qualitative attributes of a given genotypes in order to differentiate their usefulness, structure, genetic variability and relationships among them. The objectives of this study were to characterize elite maize inbred lines adapted to highland agro-ecologies and classify groups of similar inbred lines by means of cluster and principal component analysis based on morpho-agronomic and SNP markers data. A total of twenty-three maize inbred lines of highland breeding department at Ambo Plant Protection Research Center formed the core plant materials in the current experiment for 23 morpho-agronomic traits and SNP markers characterization. The evaluated lines were sown in alpha lattice design 12 × 2. It was planted in two replications at each locations (Ambo and Holetta agricultural research centers). The inbred-lines were highly significantly different for all traits evaluated (p ≤ 0.01). The PCA indicated that the first nine principal components (PCs) with eigen value greater than unity accounted for 83% of the entire diversity among 23 inbred lines for all traits. Cluster analysis performed on the basis morpho-agronomic traits using unweighted paired group method arithmetic averages (UPGMA) grouped 23 tested lines in to five distinct classes and an outlier genotype whereas cluster analysis based on molecular resulted from distance matrix of genetic categorized the entries into four main groups. Five inbred lines (L5, L8, L18, L12 and L7) with comparatively high yielder and other phenotypic characters were selected using the morpho-agronomic traits and SNP based genotyping for cultivar development and germplasm utilization.