Data from: Ecological factors influence balancing selection on leaf chemical profiles of a wildflower

Balancing selection is frequently invoked as a mechanism to maintain
variation within and across populations. However, rigorous tests
demonstrating balancing selection operating in nature are scarce,
particularly on complex traits, which frequently display high levels of
variation. Leveraging a focal polymorphism, leaf chemical profile in a
perennial wildflower (Boechera stricta, Brassicaceae), we investigated the
ecological and genetic mechanisms that may influence the maintenance of
variation in this trait. A suite of common garden and greenhouse
experiments showed that the alleles underlying variation in chemical
profile have contrasting fitness effects across environments, implicating
two ecological drivers of selection on chemical profile: herbivory and
drought. Phenotype-environment associations and molecular genetic analyses
revealed additional evidence of past selection by these drivers. Together,
these data are consistent with balancing selection on chemical profile,
likely caused by pleiotropic effects of genes that influence secondary
chemical biosynthesis on herbivore defense and drought response.