Cleistogamy is effective in

Options

A. Oryza sativa
B. Brassica campestris
C. Allium cepa
D. Pisum sativum.

Answer

**Step-by-Step Solution:**

1. **Understanding Cleistogamy:**
- Cleistogamy refers to the phenomenon where flowers remain closed and do not open. These flowers are typically bisexual, containing both male (stamens) and female (pistils) reproductive organs, allowing for self-pollination.

2. **Purpose of Cleistogamy:**
- The main advantage of cleistogamous flowers is that they ensure self-pollination, which helps in maintaining genetic stability and can be advantageous in stable environments where cross-pollination might not be necessary.

3. **Analyzing the Options:**
- **Oryza sativa (Rice):** This plant exhibits cleistogamous flowers, making it a candidate for the correct answer.
- **Brassica campestris (Mustard):** This plant has chasmogamous flowers, which are open and allow for cross-pollination.
- **Allium sepa (Onion):** Similar to Brassica, onions also have chasmogamous flowers.
- **Pisum sativum (Pea):** Peas are known for having chasmogamous flowers as well.

4. **Conclusion:**
- Among the given options, the only plant that shows cleistogamy is **Oryza sativa**. Therefore, the correct answer to the question "Cleistogamy is effective in?" is **A) Oryza sativa**.

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