What is the basic reason behind leaves remaining above the water in rice plant ?

Options

A. Bolting due to gibberellin
B. Apical dominance due to auxin
C. Internodal elongation due to ethylene
D. Due to photoperiodism

Answer

To answer the question regarding the basic reason behind leaves remaining above the water in rice plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Rice Plant's Growth**:
- Rice plants are typically grown in flooded conditions, where water covers the soil. In such environments, it is essential for the plant to have its leaves above the water to perform photosynthesis.

2. **Identifying Key Growth Factors**:
- The growth of rice plants is influenced by various hormones, including gibberellins, auxins, and ethylene. Each of these hormones plays a role in plant growth and development.

3. **Evaluating the Options**:
- **Option A: Bolting due to gibberellin** - While gibberellins promote growth, bolting (the rapid elongation of the stem) is not the main reason for leaves remaining above water.
- **Option B: Apical dominance due to auxin** - Auxins promote the growth of the main stem, but rice plants are not particularly tall, making this option less relevant.
- **Option C: Internodal elongation due to ethylene** - Ethylene promotes the elongation of the internodes (the segments between nodes on the stem). This elongation allows the leaves to rise above the water surface, facilitating photosynthesis.
- **Option D: Photoperiodism** - This refers to the plant's response to the length of day and night, which is not directly related to the leaves' position above water.

4. **Conclusion**:
- The correct answer is **Option C: Internodal elongation due to ethylene**. This elongation allows the leaves to remain above the water, enabling the plant to carry out photosynthesis effectively.

### Final Answer:
The basic reason behind leaves remaining above the water in rice plants is due to **internodal elongation caused by ethylene**.

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