Brown rust of wheal is caused by

Options

A. Ustilago nuda tritici
B. Puccinia recondita
C. Puccinia striiformis
D. Puccinia graminis tritici

Answer

**Step-by-Step Solution:**

1. **Understanding the Disease**: The question asks about the causative agent of brown rust in wheat. Brown rust is a significant disease affecting wheat crops, characterized by reddish-brown patches on leaves.

2. **Identifying the Options**: The options given are:
- A) Ustilago nudatriticae
- B) Puccinia recondita
- C) Puccinia striiformis
- D) Puccinia graminis triticae

3. **Analyzing the Causative Agents**:
- Ustilago nudatriticae is known to cause a different disease (wheat loose smut).
- Puccinia recondita is associated with leaf rust, not brown rust.
- Puccinia striiformis is the cause of wheat yellow rust.
- Puccinia graminis triticae is known to cause brown rust in wheat.

4. **Confirming the Correct Answer**: Based on the analysis, the correct causative agent for brown rust of wheat is **Puccinia graminis triticae**.

5. **Conclusion**: Therefore, the answer to the question "Brown rust of wheat is caused by?" is **Puccinia graminis triticae** (Option D).

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