Meristem maturation and inflorescence architecture — lessons from the Solanaceae

Abstract

Plant apical meristems (AMs) grow continuously by delicately balancing cells leaving at the periphery to form lateral organs with slowly dividing central domain cells that replenish reservoirs of pluripotent cells. This balance can be modified by signals originating from within and outside the meristem, and their integration results in a gradual maturation process that often culminates with the meristem differentiating into a flower. Accompanying this 'meristem maturation' are changes in spacing and size of lateral organs and in rates at which lateral meristems are released from apical dominance. Modulation of distinct meristem maturation parameters through environmental and genetic changes underlies the remarkable diversity of shoot architectures. Here, we discuss recent studies relating the dynamics of meristem maturation with organization of floral branching systems--inflorescences--in the nightshades. From this context, we suggest general principles on how factors coordinating meristem maturation impact shoot organization more broadly.