A genetic framework for regulation and seasonal adaptation of shoot architecture in hybrid aspen

Significance Control of branching is critical for optimizing growth and adaptation in plants. In contrast with annuals, in perennial plants growing in temperate and boreal regions, branching must be controlled temporally to adapt to seasonal changes. The molecular pathways regulating branching and its adaptation to seasonal changes are not well understood in perennial plants. We identified the genetic network underlying the control of branching and elucidated its role in branching by seasonal cues in model tree hybrid aspen. Our results reveal components mediating photoperiodic control of growth in trees, and conserved branching regulators have been integrated into a genetic network to control branching and facilitate its adaptation to seasonal changes experienced by long-lived perennial plants.