1. Ecological factors influence balancing selection on leaf chemical profiles of a wildflower
- Author
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Chase L. Nuñez, Lauren N. Carley, Julius P. Mojica, Kathryn Ghattas, Baosheng Wang, Chia-Yu Chen, Thomas Mitchell-Olds, Catherine A. Rushworth, Michael Reichelt, Jonathan Gershenzon, Jing Wang, Rose A. Keith, Carrie F. Olson-Manning, K.V.S.K. Prasad, Ya-Ping Lin, Pei-Min Yeh, Emily Chan, Che-Wei Hsu, Maggie R. Wagner, and Cheng-Ruei Lee
- Subjects
0106 biological sciences ,0301 basic medicine ,Herbivore ,Polymorphism, Genetic ,Ecology ,Wildflower ,Mechanism (biology) ,Biology ,Balancing selection ,biology.organism_classification ,01 natural sciences ,Article ,Plant Leaves ,03 medical and health sciences ,030104 developmental biology ,Pleiotropy ,Brassicaceae ,Boechera stricta ,Herbivory ,Selection, Genetic ,Allele ,Ecology, Evolution, Behavior and Systematics ,Selection (genetic algorithm) ,010606 plant biology & botany - Abstract
Balancing selection is frequently invoked as a mechanism that maintains variation within and across populations. However, there are few examples of balancing selection operating on loci underpinning complex traits, which frequently display high levels of variation. We investigated mechanisms that may maintain variation in a focal polymorphism—leaf chemical profiles of a perennial wildflower (Boechera stricta, Brassicaceae)—explicitly interrogating multiple ecological and genetic processes including spatial variation in selection, antagonistic pleiotropy, and frequency-dependent selection. 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 secondary chemical biosynthesis genes on herbivore defense and drought response., Editor’s Summary: Evidence for balancing selection acting on loci that control complex traits is limited. Here, the authors show evidence for past selection on chemical profile in a perennial wildflower by two ecological drivers, herbivory and drought, consistent with balancing selection on this trait.
- Published
- 2021