The causative organism for brown rust of wheat is ?

Options

A. Aspergillus
B. Collectotrichum
C. Xanthomonas
D. Puccinia

Answer

To determine the causative organism for brown rust of wheat, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Disease**:
- Brown rust of wheat is also known as leaf rust. It is a significant disease that affects wheat and other cereal crops.

2. **Identify the Causative Agent**:
- The causative organism for brown rust of wheat is a fungus. Specifically, it is caused by the fungus *Puccinia triticina*.

3. **Evaluate the Options**:
- The question provides four options:
- **Aspergillus**: A common mold that causes Aspergillosis, not related to wheat rust.
- **Colletotrichum**: A genus of fungi that causes post-harvest rots, not brown rust.
- **Xanthomonas**: A genus of bacteria that causes bacterial spots, not related to rust diseases.
- **Puccinia**: This is the correct genus that includes the species responsible for brown rust.

4. **Select the Correct Answer**:
- Based on the evaluation of the options, the correct answer is **Puccinia**.

### Final Answer:
The causative organism for brown rust of wheat is **Puccinia**.

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