Genetic diversity assessment and relationship among tropical-yellow endosperm maize inbred lines using SSR markers.

摘要

Maize is the most important food crop in sub-Saharan Africa. Tropical-adapted yellow maize inbred lines can be used as source of provision of pro-vitamin A, needed by millions of African children that suffer from vitamin A deficiency. A substantial variation of pro-vitamin A content is known to exist among available inbred lines. The objective of this study was to assess the diversity and relationship among 38 tropical-adapted maize inbred lines. The lines were investigated using 87 SSR markers. Seventy-five (75) SSR markers were polymorphic across the 38 inbred lines and generated a total of 297 alleles. The polymorphic information content (PIC) values obtained for the polymorphic SSR markers varied from 0.17 to 0.84 with an average of 0.56 .The number of polymorphic alleles per locus ranged from 2 to 11 with a mean of 3.96. Genetic distance (GD) values among all pairs of inbred lines varied from 0.007 to 0.59 with an average of 0.45. Cluster and principal coordinate analyses based on genetic distance from SSR data showed two well defined main groups of the 38 inbred lines, consistent with their pedigrees. The study has revealed a considerable level of genetic diversity among the inbred lines. The genetic potential that exists will facilitate the selection of parents with diverse alleles for development of new maize genotypes with higher pro-vitamin A level.