Distinct Genetic Architectures for Phenotypes and their Plasticities in Zea mays

Phenotypic plasticity describes intra-individual phenotypic variation in response to different environmental conditions. As world population growth and climate change stress food production systems, understanding the genetic control of phenotypic plasticity in crops such as maize becomes of paramount importance for maintaining and increasing yields. Here, we report the results of genome-wide association analyses of multiple phenotypes and two measures of phenotypic plasticity in the maize nested association mapping (US-NAM) population grown in multiple environments and genotyped with ~2.5 million single nucleotide polymorphisms. We show across all traits that the candidate genes for mean phenotypes and plasticity measures form three structurally and functionally distinct groups. Such independent genetic control of mean phenotypes and plasticity suggests that breeders could select semi-independently for these characteristics of phenotypes, thereby exploiting plasticity according to the demands of the target performance environment.