In grafting, the portion to be grafted on the main part is called :

Options

A. Adventitious bud
B. Stem
C. Stock
D. scion

Answer

To answer the question "In grafting, the portion to be grafted on the main part is called:", we will analyze the options provided and identify the correct term.

### Step-by-Step Solution:

1. **Understanding Grafting**: Grafting is a horticultural technique where a portion of one plant (the scion) is attached to the root system of another plant (the stock). The goal is to combine the best characteristics of both plants.

2. **Analyzing the Options**:
- **Option 1: Adventitious bud**: Adventitious buds are those that arise in unusual places, such as on stems or roots. This term does not specifically refer to the portion being grafted.
- **Option 2: Stem**: While the stem is a part of the plant, it is not the correct term for the portion being grafted. The stem is the main axis of the plant.
- **Option 3: Stalk**: The term "stalk" can refer to any part of a plant that supports another part, but it does not specifically denote the grafted portion.
- **Option 4: Scion**: The scion is the correct term for the portion of the plant that is grafted onto the main plant (the stock). It is the upper part that will grow and develop into a new plant.

3. **Conclusion**: After evaluating all the options, the correct answer is **Option 4: Scion**.

### Final Answer:
In grafting, the portion to be grafted on the main part is called the **Scion**.

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