Question

For union between stock and scion in grafting, which one is the first to occur
A. Formation of callus
B. Production of plasmodesmata
C. Differentiation of new vascular tissues
D. Regeneration of cortex and epidermis

Answer 1

Vegetative propagation is a type of asexual method of reproduction in which plants are reproduced without gametic fusion. It includes several artificial methods like budding, grafting, layering, and tissue culture.

Complete step by step answer:
Grafting is an artificial method in which plants undergo vegetative propagation. It is done by joining two plant parts from different plants and allowing them to join by tissue regeneration. In grafting, we join two plant parts namely stock and scion. Here, the part of the plant which is added is called scion and this part lacks roots. Scion is joined with stock which is adhered to the ground and it contains roots in it. Stock and scion are joined together and allowed to grow as a new plant. In this method, the meristematic tissue of both stock and scion are joint together which is capable of cell division. This tissue is called cambium. The compatibility between stock and scion is essential for a successful graft; not all plants can be used for grafting. While grafting, the first step is the formation of new tissue called a callus. This tissue is generated on the cut ends of both stock and scion and their cambium gets joined together.
Hence the correct option is A.

Note: The budding is another method of artificial vegetative propagation. In this method, bud from one plant is grown on the other plant. Budding is also called bud grafting. In this method, only a single bud is joined to the stock instead of the whole scion.