Out of America: tracing the genetic footprints of the global diffusion of maize

Authors: MIR, C - University Of Paris; ZERJAL, T - Agro Paris Tech; COMBES, V - University Of Paris; DUMAS, F - University Of Paris; MADUR, D - University Of Paris; BEDOYA, C - International Maize & Wheat Improvement Center (CIMMYT); DREISIGACKER, S - International Maize & Wheat Improvement Center (CIMMYT); FRANCO, J - International Institute Of Tropical Agriculture (IITA); GRUDLOYMA, P - Department Of Agriculture - Thailand; HAO, P - Agricultural Genetics Institute (AGI); HEARNE, S - International Institute Of Tropical Agriculture (IITA); JAMPATONG, C - Kasetsart University; MUTHAMIA, Z - Kenya Agricultural Research Institute; VAN TRUONG, N - Agricultural Genetics Institute (AGI); PRASANNA, M - Agricultural Research Institute Of India; TABA, S - International Maize & Wheat Improvement Center (CIMMYT); XIE, C - Chinese Academy Of Agricultural Sciences; YUNUS, Y - Indonesian Agency For Agricultural Research And Development; ZHANG, S - Chinese Academy Of Agricultural Sciences; Warburton, Marilyn; CHARCOSSET, A - University Of Paris

Submitted to: Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/12/2013
Publication Date: 8/7/2013
Citation: Mir, C., Zerjal, T., Combes, V., Dumas, F., Madur, D., Bedoya, C., Dreisigacker, S., Franco, J., Grudloyma, P., Hao, P.X., Hearne, S., Jampatong, C., Muthamia, Z., Van Truong, N., Prasanna, M., Taba, S., Xie, C.X., Yunus, Y., Zhang, S., Warburton, M.L., Charcosset, A. 2013. Out of America: tracing the genetic footprints of the global diffusion of maize. Theoretical and Applied Genetics. 126:2671–2682. https://doi.org/10.1007/s00122-013-2164-z.
DOI: https://doi.org/10.1007/s00122-013-2164-z

Interpretive Summary: Maize (corn) is grown in nearly every country of the world and distinct varieties are bred to match local growing conditions. To help this process, understanding how different old, traditional varieties are related to each other is important. Knowing how corn was moved out of Mexico, where it was first domesticated, and into other countries around the world provides evidence of genetic relationships. Historical records provide some of this information, but where records are incomplete or contradictory (which is especially true in Africa and Asia), genetic data can be used. Genetic fingerprinting of 11,985 individual plants of representative traditional maize varieties (called landraces) from around the world with DNA markers allows us to follow how maize diffused out of seven ancestral American clusters of landraces comprising genetically distinct population centers. These results are largely congruent with historical reports of global maize diffusion, but also shed new light on the first introductions of maize into Africa and Asia. By providing a first globally comprehensive genetic characterization of maize landraces, this study illuminates the post-domestication evolutionary history of this major crop and provides data that will be crucial for plant improvement of maize in different regions of the world.

Technical Abstract: Despite the importance of maize cultivation in nearly every country of the world, the routes of diffusion and continued evolution outside of the Americas is still largely enigmatic, especially in Africa and Asia. By genotyping 11,985 individual plants of representative landraces from around the world with DNA markers, we can follow how maize diffused out of seven ancestral American clusters of landraces comprising genetically distinct population centers. These results are largely congruent with historical reports of global maize diffusion, but also shed new light on the first introductions of maize into Africa and Asia. By providing a first globally comprehensive genetic characterization of maize landraces, this study illuminates the post-domestication evolutionary history of this major crop and explains the species level variation that may be tapped for plant improvement in different regions of the world.