Characterization of introgression from the teosinte Zea mays ssp. mexicana to Mexican highland maize

Unidad de Genómica Avanzada (LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, Mexico
Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, United States
Department of Plant Sciences, Center for Population Biology, and Genome Center, University of California, Davis, Davis, United States
DOI
10.7287/peerj.preprints.27489v1
Subject Areas
Agricultural Science, Evolutionary Studies, Genetics, Genomics, Plant Science
Keywords
Maize, Teosinte, Introgression, Local adaptation
Copyright
© 2019 Gonzalez-Segovia et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Gonzalez-Segovia E, Pérez-Limon S, Cíntora-Martínez C, Guerrero-Zavala A, Jansen G, Hufford MB, Ross-Ibarra J, Sawers RJH. 2019. Characterization of introgression from the teosinte Zea mays ssp. mexicana to Mexican highland maize. PeerJ Preprints 7:e27489v1

Abstract

Background. The spread of maize cultivation to the highlands of central Mexico was accompanied by substantial introgression from the endemic wild teosinte Zea mays ssp. mexicana, prompting the hypothesis that the transfer of beneficial variation facilitated local adaptation.

Methods. We used novel whole-genome sequence data to map regions of Zea mays ssp. mexicana introgression in three Mexican highland maize individuals. We generated a genetic linkage map and performed Quantitative Trait Locus mapping in an F2 population derived from a cross between lowland and highland maize individuals.

Results. Introgression regions ranged in size from several hundred base pairs to Megabase-scale events. Gene density within introgression regions was comparable to the genome as a whole, and over one thousand annotated genes were located within introgression events. Quantitative Trait Locus mapping identified a small number of loci linked to traits characteristic of Mexican highland maize.

Discussion. Although there was no strong evidence to associate quantitative trait loci with regions of introgression, we nonetheless identified many Mexican highland alleles of introgressed origin that carry potentially functional sequence variants. The impact of introgression on stress tolerance and yield in the highland environment remains to be fully characterized.

Author Comment

This is a submission to PeerJ for review.

Supplemental Information

Supporting Figure S1 and Tables S10 - S17

DOI: 10.7287/peerj.preprints.27489v1/supp-1

Introgression and recombination at gene models

DOI: 10.7287/peerj.preprints.27489v1/supp-4

SNPs at introgression regions fixed in Mexican highland individuals

DOI: 10.7287/peerj.preprints.27489v1/supp-5

fd output by windows - highland test set

DOI: 10.7287/peerj.preprints.27489v1/supp-6

fd output by windows - lowland null set

DOI: 10.7287/peerj.preprints.27489v1/supp-7

Local recombination rate at grid positions

DOI: 10.7287/peerj.preprints.27489v1/supp-8

Local recombination rate at markers

DOI: 10.7287/peerj.preprints.27489v1/supp-9

R/QTL cross object for RVxPT cross

DOI: 10.7287/peerj.preprints.27489v1/supp-10