Flowering time regulation through the lens of evolution

Flowering, the onset of reproductive development, marks a critical transition in the angiosperm life cycle. In the model plant Arabidopsis thaliana, the process is tightly regulated by a complex network of approximately 300 genes organized into distinct pathways. This mini-review examines the genetic and molecular mechanisms regulating flowering time from an evolutionary perspective. Our analysis reveals that genes involved in the age and photoperiod pathways are evolutionarily ancient and highly conserved across bryophytes and vascular plants. In contrast, other regulatory modules appear to have evolved more recently, likely through the repurposing of existing genes or adaptations to environmental changes. We propose that future research should shift away from studying flowering regulation mechanisms in individual model plants to exploring the evolution of flowering time pathways and their underlying drivers. Adopting an evolutionary perspective may ultimately illuminate the fundamental principles governing the timing of reproductive development in plants.