Which is wrong combination of disease and its casual organism in context of silkworm?

Options

A. Pebrine - Nosema bombycis
B. Muscardine - Spicaria
C. Muscardine - Botrytis
D. Flacherie - Nuclear polyhedral virus

Answer

To determine the wrong combination of disease and its causal organism in the context of silkworms, we will analyze the provided options step by step.

### Step-by-Step Solution:

1. **Identify the Diseases and Their Causal Organisms**:
- **Pebrine**: Caused by **Nosema bombicis** (a protozoan).
- **Muscadine**: Caused by **Spicaria** (a fungus).
- **Muscadine**: Caused by **Botrytis** (another fungus).
- **Flasheri**: Caused by **Nuclear Polyhedral Virus** (but it is mentioned that it is caused by bacteria).

2. **Evaluate Each Combination**:
- **Pebrine and Nosema bombicis**: This combination is correct as Pebrine is indeed caused by this protozoan.
- **Muscadine and Spicaria**: This combination is also correct since Spicaria is a fungus that causes Muscadine disease.
- **Muscadine and Botrytis**: This is another correct combination, as Botrytis is known to cause a type of Muscadine disease.
- **Flasheri and Nuclear Polyhedral Virus**: This combination is incorrect because Flasheri is actually caused by bacteria (specifically Streptococcus or Septococci bacillus), not by a virus.

3. **Conclusion**:
- The wrong combination of disease and its causal organism in the context of silkworms is **Flasheri and Nuclear Polyhedral Virus**.

### Final Answer:
The wrong combination is **Flasheri and Nuclear Polyhedral Virus**.

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