Relationships of the wild peanut species, section Arachis: A resource for botanical classification, crop improvement, and germplasm management

Authors: LEAL-BERTIOLI, SORAYA - University Of Georgia; DE BLAS, FRANCISCO - Instituto De Botánica Del Nordeste; CHAVARRO, CAROLINA - University Of Georgia; SIMPSON, CHARLES - Texas A&M University; VALLS, JOSE - Embrapa; Tallury, Shyamalrau - Shyam; MORETZSOHN, MARCIO - Embrapa; CUSTODIO, ADRIANNE - Embrapa; STALKER, HAROLD - North Carolina State University; SEIJO, GUILLERMO - Instituto De Botánica Del Nordeste; BERTIOLI, DAVID - University Of Georgia

Submitted to: American Journal of Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/9/2024
Publication Date: 6/19/2024
Citation: Leal-Bertioli, S.C., De Blas, F., Chavarro, C.M., Simpson, C.E., Valls, J.F., Tallury, S.P., Moretzsohn, M.C., Custodio, A.R., Stalker, H.T., Seijo, G., Bertioli, D.J. 2024. Relationships of the wild peanut species, section Arachis: A resource for botanical classification, crop improvement, and germplasm management. American Journal of Botany. 111. Article e16357. https://doi.org/10.1002/ajb2.16357.
DOI: https://doi.org/10.1002/ajb2.16357

Interpretive Summary: Peanut wild species are a great resource for the genetic improvement of cultivated peanut. They contain several valuable traits such as disease resistances, drought tolerance and nutritional qualities to improve the cultivated peanut. A comprehensive understanding of their genetic relationship to cultivated peanut is necessary to transfer the desirable traits into cultivated types. Two hundred and seventy-two wild species entities were analyzed using DNA sequencing tools. The resulting analysis provided clear cut separation of the wild species into clusters based on their genetic relationships. This information is very valuable to develop methods to transfer desirable genes into cultivated types and also aids in the efficient management of the wild species genetic resources.

Technical Abstract: Principal Coordinate and phylogenetic analyses of this genotyping data revealed two main groups: one with all the A genome species and the other with the cytogenetically defined B, D, F, G, and K genomes as well as other species with unknown genome types. Mostly, the phylogenetic groupings demonstrated clear boundaries between assigned species. However, the phylogenetic grouping of certain species was indicative of multiple sibling species. Furthermore, some species as currently assigned, are polyphyletic, indicating the need for taxonomic revision. Notably, the definition and division of annual species were better than perennial species. This highlights the limitations of the application of classical and phylogenetic species concepts to the genus Arachis and indicates that, for some groups of accessions, alternative species concepts are more appropriate. This phylogenetic analysis, curated by the Arachis botanical collectors and scientists responsible for germplasm banks, provides detailed groundwork for future species description, classification of accessions from unknown Arachis species, and germplasm use. In the wild, this genus is under considerable threat, as natural habitats rapidly diminish due to agricultural expansion and urbanization. Given the current restrictions on new collections and transferring germplasm between countries, the ex-situ preservation in seed banks is vital in safeguarding this germplasm as an invaluable legacy for generations to come.