Dormancy Induction and Release in Buds and Seeds

Abstract

Dormancy is a complex trait in both buds and seeds, which is an important mechanism for survival during the life cycle of plants. Over the years, a vast wealth of information has been generated on how environmental and developmental signals impact dormancy in buds and seeds. At the molecular level, these studies have identified many factors including light (photoperiod), temperature (cold), hormones, circadian clock, and epigenetic regulation that control dormancy-associated genes regulating induction and release of dormancy in buds and seeds. Due to intrinsic differences between buds and seeds across a multitude of plant species, it should not be surprising that similar and dissimilar signals may control different phases of dormancy. This review focuses on the main similarities in gene expression and molecular mechanisms involved in bud and seed dormancy and release. A model perennial weed, leafy spurge, is presented as an example to compare commonalities in gene expression and molecular mechanisms during bud and seed dormancy and release. The study indicated that the physiological state of dormant imbibed, but growth competent seeds (21d C) are more analogous to paradormant buds than that of ecodormant buds. In addition, common molecular mechanisms associated with dormancy transitions in buds and seeds involved processes associated with abscisic acid- and auxin-signaling and transport, cell cycle, and AP2/ERF transcription factors or their up-stream regulators.