Select the odd one from given herbicides.

Options

A. Cactoblastis
B. Alternaria
C. Fusarium
D. Phytophthora

Answer

**Step-by-Step Solution:**

1. **Identify the Given Options**: The question asks to select the odd one out from a list of herbicides. The options provided are Cactoblastis, Alternaria, Fusarium, and Phytophthora.

2. **Understand Each Option**:
- **Cactoblastis**: This is a biocontrol agent that involves the use of a cactus moth to control cactus plants (specifically Opuntia). It is not classified as a herbicide.
- **Alternaria**: This is a type of fungus that causes brown spot disease in plants. It is treated with fungicides, which are used to control fungal infections.
- **Fusarium**: This refers to a genus of fungi that can cause wilt diseases in plants. Herbicides may be used to manage the effects of this disease, but it is primarily a fungal disease.
- **Phytophthora**: This is a genus of plant-damaging oomycetes that cause root rot diseases. Similar to Fusarium, herbicides may be used in management, but it is also primarily associated with fungal infections.

3. **Classify Each Option**:
- Cactoblastis is a biocontrol method.
- Alternaria is associated with fungicides.
- Fusarium is associated with herbicides and fungicides.
- Phytophthora is also associated with herbicides and fungicides.

4. **Determine the Odd One Out**:
- Since Cactoblastis is a biocontrol agent and not a herbicide, while the other three options (Alternaria, Fusarium, and Phytophthora) are related to diseases that can be treated with fungicides or herbicides, Cactoblastis is the odd one out.

5. **Conclusion**: The odd one from the given herbicides is **Cactoblastis**.

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