Aecial stages of Puccinia develop on

Options

A. Wheat leaves
B. Wheat stem
C. Upper surface of Barberry leaf
D. Lower surface of Barberry leaf.

Answer

To answer the question about where the aecial stages of Puccinia develop, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Organism**: Puccinia is a genus of fungi, commonly known as rust fungi. They have a complex life cycle that includes multiple stages.

2. **Identify the Stages**: The life cycle of Puccinia includes five stages:
- Uredinal stage
- Telial stage
- Basidial stage
- Aecial stage
- Pycnial stage

3. **Determine Host Plants**: The first three stages (uredinal, telial, and basidial) occur on wheat plants, while the last two stages (aecial and pycnial) occur on barberry plants.

4. **Focus on the Aecial Stage**: The question specifically asks about the aecial stage. This stage develops on the barberry plant.

5. **Identify the Leaf Surface**: The aecial stage is primarily found on the upper surface of the barberry leaves. It is characterized by small clusters of cup-shaped structures filled with orange or yellow spores.

6. **Conclusion**: Based on the information gathered, the aecial stages of Puccinia develop on the upper surface of the barberry leaf.

### Final Answer:
The aecial stages of Puccinia develop on the upper surface of the barberry leaf.

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