Genetic diversity and population structure of some Nigerian and four African countries' sorghum landraces [Sorghum bicolor (L.) Moench] using Genotyping-By-Sequencing (GBS) SNP markers

A genotyping-by-sequencing (GBS) approach was used in this study to assess the genetic variability and population structure of fifty sorghum landrace accessions collected from the major sorghum growing areas in Nigeria and four other African countries. There were 7078 SNP markers found in the sorghum genome that were widely distributed. An average polymorphism information content (PIC) value of 0.26 was observed for the SNP markers. Gene diversity (He) was substantial among the selected accessions (0.30). Nigeria's north-east accessions showed the highest gene diversity (0.32). Although molecular variation varied by only 2% among populations and by 98% within populations, principal coordinate analysis and cluster analysis revealed three major groups unrelated to geographical origin. This is an indication of high gene flow among populations (Nm = 7.71). However, due to the considerable similarity within populations, many accessions from similar states tend to cluster together. The population structure analysis at K=3 revealed three subpopulations, with 42% of the accessions evaluated being admixed together. A high number of private alleles (162) were identified in accession samples. This shows the potential for beneficial traits in sorghum breeding.(c) 2023 SAAB. Published by Elsevier B.V. All rights reserved.