68 Oral - Keynote #4 (Session Chairs) and Awards
Friday June 10, 4:20 PM - 4:50 PM
Uncovering the genetic basis of local adaptation in maize with large-scale multi-environment trials
Authors: Daniel Runcie 1; Daniel Gates 1; Garrett Janzen 2; J. Alberto Romero Navarro 3; Martha Willcox 4; Kai Sonder 4; Samantha Snodgrass 2; Fausto Rodriguez-Zapata 5,6; Ruairidh Sawers 7; Ruben Rellan-Alvarez 6; Edward Buckler 3; Sarah Hearne 4; Matthew Hufford 2; Jeffrey Ross-Ibarra 1
Affiliations: 1) University of California Davis, Davis, CA; 2) Iowa St University, Ames, IA; 3) Cornell University, Ithica, NY; 4) International Maize and Wheat Improvement Center (CIMMYT), Mexico; 5) Laboratorio Nacional de Genomica para la Biodiversidad/Unidad de Genómica Avanzada, Cinvestav, Mexico; 6) North Carolina State University, Raleigh, NC; 7) The Pennsylvania St University, State College, PA
Keywords: Theory & Method Development
Threats to crop production due to climate change are one of the greatest challenges facing society today. Considerable adaptive variation exists in traditional landraces and germplasm collections, but effective use of this diverse germplasm requires separating adaptive alleles from linked deleterious variants. One strategy to identify adaptive loci is to grow panels of varieties in multiple environmental contexts and use genome-wide association analyses (GWAS) to identify loci exhibiting adaptive patterns such as fitness benefits in specific environments or geographic clustering of alleles by environmental characteristics. However, the statistical analysis of such gene-environment interactions and gene-environment associations is challenging because of issues of the considerable population and spatial structure in traditional landrace collections and the high-dimensional nature of performance traits measured across multiple locations. We will present a genome-wide association analysis of performance traits in maize using nearly 4000 traditional landraces broadly representing the breadth of genetic diversity of maize in Central and South America. Partially overlapping subsets of these varieties were grown in 23 field trials spanning multiple environmental gradients in Mexico. We will highlight several methodological developments in the analysis of multi-environment trials allowing accurate and efficient genome-wide modeling of allele-environment interactions and the patterns of plasticity along environmental gradients. Our results produce a detailed and fine-scale map of the properties of potentially beneficial alleles available in the traditional landraces housed in maize germplasm collections.