Genetic diversity analysis of CIMMYT-mid-altitude maize inbred lines using AFLP markers

Abstract

Information on genetic variability of maize (Zea mays L.) inbred lines can be helpful in developing high yielding varieties in a breeding programme. The objectives of this study were to investigate genetic diversity among 21 CIMMYT-mid-altitude maize inbred lines and classify them into putative heterotic groups using Amplified Fragment Length Polymorphism (AFLP) markers. Six Eco RI/Mse I primer combinations were employed to generate AFLP fragments. From a total of 334 AFLP fragments scored, 275 (81.2 %) were polymorphic among the inbred lines. Genetic distance (GD) varied from 0.38 to 0.70, with an average of 0.60. The high mean variability determined among the inbred lines indicates possibilities for the exploitation of heterosis and genetic improvement of desirable traits through selection and cross breeding. Cluster analysis using average linkage methods (UPGMA) revealed at least four putative groups of lines. AFLP proved to be a robust assay, revealing great power to detect genetic variability and classify the inbred lines into putative heterotic groups. This information can be used to initiate heterotic source populations and to guide crossing activities between divergent inbred lines for the development of hybrid varieties.