A fungus which secretes abscisic acid is

Options

A. Aspergillus
B. Gibberella
C. Cercospore
D. Alternaria.

Answer

To solve the question "A fungus which secretes abscisic acid is," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Key Term**: The question is asking about a specific fungus that secretes abscisic acid. Abscisic acid is a plant hormone that plays a role in various physiological processes.

2. **Review the Options**: The options provided include:
- Sarcospora
- Aspergillus niger
- Gibberella
- Alternaria

3. **Analyze Each Option**:
- **Sarcospora**: This fungus is known for secreting abscisic acid, which is crucial for its growth.
- **Aspergillus niger**: This fungus is primarily known for causing black mold and does not secrete abscisic acid.
- **Gibberella**: This fungus is associated with the isolation of gibberellin, another plant hormone, not abscisic acid.
- **Alternaria**: This fungus is known for causing infections in plants, specifically brown spots, and does not secrete abscisic acid.

4. **Select the Correct Answer**: Based on the analysis, the correct answer is Sarcospora, as it is the only fungus listed that is known to secrete abscisic acid.

### Final Answer:
The fungus which secretes abscisic acid is **Sarcospora**.

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