The viruses which are excellent candidates for speciens - specific , narrow spectrum, insecticidal applications are

Options

A. Mainly belonging to the genus Nucleopolyhedrovirus
B. Not suitable for Integrated Pest Management
C. Can cause harm to useful insets as well
D. Can cause soil pollution

Answer

To solve the question regarding which viruses are excellent candidates for species-specific, narrow-spectrum insecticidal applications, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for viruses that are specifically effective against certain insect species and have a narrow spectrum of activity, meaning they do not harm non-target organisms.

2. **Identify the Options**: The options provided include:
- Viruses belonging to the genus Nucleopolyhedrovirus (NPV)
- Not suitable for integrated pest management
- Can cause harm to useful insects
- Can cause soil pollution

3. **Analyze the First Option**: The Nucleopolyhedrovirus (NPV) is known to be a biopesticide that specifically targets certain insect pests, particularly moths and butterflies. This makes it a strong candidate for species-specific applications.

4. **Evaluate the Integrated Pest Management (IPM) Suitability**: NPV is indeed suitable for integrated pest management as it is eco-friendly, has low residual toxicity, and does not negatively impact beneficial insects or other organisms.

5. **Assess the Impact on Useful Insects**: NPV is designed to target specific pests and does not harm beneficial insects, making the claim that it can cause harm to useful insects incorrect.

6. **Consider Soil Pollution**: NPV is eco-friendly and does not contribute to soil pollution, which makes this option also incorrect.

7. **Conclusion**: Based on the analysis, the correct answer is that the viruses which are excellent candidates for species-specific, narrow-spectrum insecticidal applications are those that belong to the genus Nucleopolyhedrovirus (NPV).

### Final Answer:
The viruses which are excellent candidates for species-specific, narrow-spectrum insecticidal applications are those that belong to the genus Nucleopolyhedrovirus (NPV).

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