Common cause of seed and bud dormancy is the presence of

Options

A. Ethylene
B. Cytokinins
C. Abscisic acid
D. Both B and C

Answer

To answer the question regarding the common cause of seed and bud dormancy, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Seed and Bud Dormancy**:
- Seed and bud dormancy refers to a state in which seeds or buds are inactive and do not germinate or grow. This state is crucial for survival, allowing seeds to remain viable until conditions are favorable for growth.

2. **Identifying Causes of Dormancy**:
- There are several factors that can lead to dormancy, including:
- **Impermeable Seed Coats**: Some seeds have hard or impermeable coats that prevent water absorption, which is necessary for germination.
- **Unfavorable Environmental Conditions**: Conditions such as extreme temperatures, lack of moisture, or inappropriate light can inhibit germination.
- **Presence of Inhibitors**: Certain chemicals or hormones present in the seed can prevent germination until they are washed away or broken down.

3. **Role of Hormones**:
- Hormones play a significant role in regulating dormancy:
- **Abscisic Acid (ABA)**: This hormone is often referred to as the "stress hormone" because it helps seeds cope with unfavorable conditions by inducing dormancy.
- **Ethylene**: This hormone is associated with the induction of seed and bud dormancy as well.

4. **Conclusion**:
- Based on the information provided, both **Abscisic Acid** and **Ethylene** are common causes of seed and bud dormancy. Therefore, the correct answers to the question are the presence of these hormones.

### Final Answer:
The common causes of seed and bud dormancy are the presence of **Abscisic Acid** and **Ethylene**.

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