Which of the following physiological activity is not induced by Auxins in plants

Options

A. Rooting in stem cutting
B. Xylen differnation
C. Induction of parthencarpy
D. Induction of abscission of yong leaves and furits

Answer

To determine which physiological activity is not induced by auxins in plants, let's analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Auxins**: Auxins are plant hormones, primarily known as indole-3-acetic acid (IAA). They play a crucial role in various growth processes in plants.

2. **Evaluating Each Option**:
- **Option A: Rooting in Stem Cutting**: Auxins promote the development of roots from cuttings. This is a well-known application of auxins in horticulture. Therefore, this activity is induced by auxins.

- **Option B: Xylem Differentiation**: Auxins stimulate xylem differentiation, which is essential for the transport of water and nutrients in plants. This activity is also induced by auxins.

- **Option C: Induction of Parthenocarpy**: Auxins are involved in inducing parthenocarpy, which is the development of fruit without fertilization. This is commonly used in agriculture for certain fruits. Thus, this activity is induced by auxins.

- **Option D: Induction of Abscission in Young Leaves**: Abscission refers to the process of leaves or fruits detaching from the plant. Auxins actually prevent abscission by promoting the retention of leaves and fruits. Therefore, this activity is NOT induced by auxins.

3. **Conclusion**: After evaluating all options, the physiological activity that is not induced by auxins is the **induction of abscission in young leaves**.

### Final Answer:
The correct answer is **Option D: Induction of Abscission in Young Leaves**.

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