**5. Conclusions**

In the present study, we explored the genetic diversity and relationships within and between a maize panel comprising landrace gene pools from Burkina Faso, Ghana, and Togo and compared each to a reference maize population. The analysis of genetic diversity parameters indicated ample genetic diversity in the maize panel. The four multivariate methods were consistent in dividing the maize panel into three distinct genetic groups, each capable of providing di fferent sources of variation for maize genetic enhancement. The genetic divergence of the Burkinabe gene pool was particularly remarkable. It, therefore, clearly represents an invaluable genetic resource that should be exploited to address the overarching goal of improving maize for adaptation to di fferent environments, ecosystems, and stress situations. Overall, the genetic diversity revealed in this study has provided an invaluable resource for future analyses of candidate genes for local adaptations using robust association mapping experiments.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2073-4425/11/9/1054/s1, Figure S1: Map of West Africa showing the countries of origin of the maize landraces analyzed in this study. Figure S2: Distribution of the 5974 DArTseq GBS makers across the 10 chromosomes of the 208 maize accessions. Table S1: Excel file with the description of the accessions analyzed in this study. Table S2: Excel file showing clustering of the maize 208 accessions based on 5974 DArTseq markers. Table S3: Excel file showing clustering of the four gene pools of maize accessions; Sheet 1. Burkinabe landraces; Sheet 2. Ghanaian landraces; Sheet 3. Togolese landraces; Sheet 4. Reference set. Table S4: List of accessions, and categorization into di fferent clusters by DAPC.

**Author Contributions:** Conceptualization, C.N., B.B.-A., A.L.G.-O., M.G., A.T., and A.S.-P.N.; Supervision: B.B.-A., A.L.G.-O., and A.S.-P.N.; Formal analysis, C.N., A.L.G.-O., A.P., and A.T.; Writing—original draft preparation, C.N.; Writing—review and editing, B.B.-A., A.L.G.-O., M.G., A.T., A.P., C.N., and A.S.-P.N.; Funding acquisition, B.B.-A., M.G., and A.L.G.-O. All authors have read and approved the final version of the manuscript.

**Funding:** This research was supported by the Bill and Melinda Gates Foundation through the funding support to the Stress Tolerant Maize for Africa (STMA) Project (Grant # OPP1134248). Genotyping was done through the Integrated Genotyping Service and Support (IGSS) platform gran<sup>t</sup> (ref. number PJ-002507). The first author was supported by a PhD fellowship from the German Federal Ministry of Education, through the West African Science Service Centre on Climate Change and Adapted Land-Use (WASCAL).

**Acknowledgments:** The first author is grateful to WASCAL for the PhD fellowship. We are grateful to the Genetic Resource Centre at IITA, Ibadan, Nigeria, and the Plant Genetics Resources Institute at Bunso, Ghana for providing the maize accessions used in this study. We also thank the IITA bioscience laboratory technicians in Ibadan, Nigeria, for sample collection and DNA extraction.

**Conflicts of Interest:** The authors declare no conflict of interest.

**Availability of Data andMaterials:** The DArTseq datasets used in the present study have been deposited at the IITA repository. CKAN: http://data.iita.org/dataset/genotypic-data-for-216-maize-inbred-lines-for-diversity-studies.
