The Effect of Artificial Selection on Phenotypic Plasticity: The Genotype by Environment Interaction Project in Maize

Remarkable productivity levels have been achieved in crop species through artificial selection and adaptation to modern agronomic practices around the world. The question remains as to whether this form of accelerated evolution has also enhanced the ability of such improved cultivars to consistently maintain high productivity across changing environmental conditions. A deeper understanding of the types of genetic architecture and modulation mechanisms controlling phenotypic plasticity, or genotype by environment (G X E) interaction, will enhance our ability to predict performance of improved crop varieties under ever-changing set of environmental conditions. This presentation will use the framework of the Genomes to Fields (G2F) G X E Maize project to assess the effect of selection on standing variation in genomic regions associated with G X E. In 2014, the G X E Maize project evaluated a collection of approximately 900 diverse maize genotypes across 23 sites in North America. Genotypes were evaluated for relevant phenological and agronomic characteristics. Climatic information was also collected in all locations. Genomic regions highly affected by selection explain a small percentage of the variability for plant height and yield G X E interaction compared to regions not differentially affected by selection. This presentation will focus on describing details related to these findings and a general description of the genetic architecture of G X E in this collection of materials.