Which one of the following is not a fungal disease ?

Options

A. Rust of wheat
B. Smut of barhra
C. Black rot of crucifers
D. Red rot of sugar cane

Explanation

### Step-by-Step Solution:

1. **Identify the Options**: The question provides four options regarding diseases:
- Rust of wheat
- Smut of barhar
- Black rot of crucifers
- Red rot of sugarcane

2. **Understand Fungal Diseases**: Fungal diseases are caused by fungi, which are a group of eukaryotic organisms. Common examples include rusts, smuts, and rots that affect various crops.

3. **Analyze Each Option**:
- **Rust of Wheat**: Caused by the fungus *Puccinia*, this is indeed a fungal disease.
- **Smut of Barhar**: Caused by the fungus *Ustilago*, this is also a fungal disease.
- **Black Rot of Crucifers**: This disease is caused by the bacterium *Xanthomonas* and is not a fungal disease.
- **Red Rot of Sugarcane**: Caused by the fungus *Colletotrichum falcatum*, this is a fungal disease.

4. **Conclusion**: Based on the analysis, the disease that is not caused by a fungus is the **Black Rot of Crucifers**, as it is caused by a bacterium.

### Final Answer:
The disease that is not a fungal disease is **Black Rot of Crucifers**.

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