2025, Vol. 13, Issue 3, Part C

author(s)
Priyanka Saini

abstract
Plants, unlike many animals, possess an extraordinary capacity for regeneration, the remarkable ability to regrow lost or damaged tissues and even entire organs. This inherent plasticity allows them to survive injuries, reproduce vegetatively, and respond dynamically to environmental changes. The mechanisms underlying plant regeneration are complex and involve a fascinating interplay of cellular reprogramming, hormonal signaling, and genetic regulation. Plant regeneration lies the concept of totipotency, the inherent ability of a single plant cell to divide and differentiate into all the diverse cell types of a complete organism. While not all plant cells retain this full potential in their differentiated state, many retain a degree of pluripotency, allowing them to de-differentiate and adopt new developmental pathways upon receiving the appropriate signals. The initiation of regeneration often begins with a wound response. Physical damage triggers a cascade of events at the injury site. Cells near the wound undergo dedifferentiation, losing their specialized characteristics and reverting to a more meristematic, undifferentiated state. This process involves changes in gene expression, allowing these cells to regain the capacity for cell division and the potential to form new tissues. A crucial step in regeneration is the formation of a callus, an unorganized mass of actively dividing parenchyma cells that accumulates at the wound site. The callus acts as a pool of undifferentiated cells from which new tissues and organs can arise. The formation of callus is heavily influenced by plant hormones, particularly auxin and cytokinin. A balanced ratio of these hormones is critical in determining the subsequent developmental fate of the callus cells. A high auxin-to-cytokinin ratio typically promotes root formation, while a high cytokinin-to-auxin ratio favors shoot development.