Seminars

Similar to flowers, thorns are determinate shoots. In Citrus species, the thorn meristem ceases its organogenetic and histogenetic activities, resulting in a hardened and sharply pointed apex. In mature Citrus thorns, a clear boundary is established: the tip accumulates lignin while the base maintains growth potential, with oil glands distributed beneath the epidermis. The determinate nature of the thorn meristem, combined with the distinct structural differences between the base and tip, establishes Citrus thorns as a promising model system for investigating stem cell arrest, oil gland development, and terminal differentiation. This presentation will highlight recent advances in these research areas using Citrus thorns as a model system and offers insights into future research directions.