Question

In case of epicotyl grafting in mango, healing union stage extends from

• A. 30-60 days
• B. 60-120 days
• C. 120-180 days
• D. 180-200 days

Hint:

Graft healing in woody plants like mango is a gradual process. A strong union needs not just callus, but also new, functional vascular connections between scion and rootstock. This typically takes several months for the plant to be considered well-established.

Answer 1

The Correct Option is C

Epicotyl grafting (or stone grafting) in mango involves joining a scion (shoot part) to a young rootstock. The "healing union stage" refers to the period required for the graft to successfully take and form a strong, lasting connection. This involves several key steps:
Callus Formation: Cells at the cut surfaces of both scion and rootstock multiply to form a mass of undifferentiated cells called callus. This bridges the gap between them.
Vascular Differentiation: New vascular tissues (xylem and phloem) must develop within the callus, connecting the vascular systems of the scion and rootstock. This is crucial for water and nutrient transport. While initial callus formation starts within weeks, the development of a robust and fully healed vascular union that makes the plant strong enough for transplanting and continued growth takes longer in woody plants like mango.
30-60 days: Callus formation is underway, but the union is still fragile.
60-120 days: Significant healing occurs, and vascular connections improve. However, the union may not be fully mature and strong.
120-180 days (approx. 4-6 months): This timeframe typically allows for the development of a well-established, strong, and sufficiently healed graft union, making the young mango plant hardy for further handling and growth.
180-200 days: While healing processes can continue, the primary strong union required for survivability and vigor is usually established before this extended period. Therefore, the 120-180 day range is considered appropriate for the graft healing union stage to be substantially complete for successful propagation. 120-180 days