Evidence that variation in root anatomy contributes to local adaptation in Mexican native maize

Abstract

Mexican native maize (Zea mays ssp. mays) is adapted to a wide range of climatic and edaphic conditions. Here, we focus specifically on the potential role of root anatomical variation in this adaptation. Given the investment required to characterize root anatomy, we present a machine-learning approach using environmental descriptors to project trait variation from a relatively small training panel onto a larger panel of genotyped and georeferenced Mexican maize accessions. The resulting models defined potential biologically relevant clines across a complex environment that we used subsequently for genotype-environment association. We found evidence of systematic variation in maize root anatomy across Mexico, notably a prevalence of trait combinations favoring a reduction in axial hydraulic conductance in varieties sourced from cooler, drier highland areas. We discuss our results in the context of previously described water-banking strategies and present candidate genes that are associated with both root anatomical and environmental variation. Our strategy is a refinement of standard environmental genome-wide association analysis that is applicable whenever a training set of georeferenced phenotypic data is available.

Keywords

GEA; local adaptation; maize; root anatomy

Published in

Evolutionary applications
2024, volume: 17, number: 3, article number: e13673
Publisher: WILEY

SLU Authors

• Heymans, Adrien

  • Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
    
  • Catholic University of Louvain

Global goals (SDG)

SDG2 Zero hunger

UKÄ Subject classification

Botany
Evolutionary Biology

Publication identifier

• DOI: https://doi.org/10.1111/eva.13673

Permanent link to this page (URI)

https://res.slu.se/id/publ/129199