Microbe used for biocontrol of pest bufferfly caterpillars is

Options

A. Saccharomyces cerevuisiae
B. Bacillus thuringiensis
C. Streptococcus sp
D. Trichoderma sp

Explanation

**Step-by-Step Solution:**

1. **Understand the Concept of Biocontrol:**
- Biocontrol refers to the use of natural organisms to control pest populations. In agriculture, this often involves using microbes to manage pests that can harm crops.

2. **Define Biopesticides:**
- Biopesticides are agents derived from natural materials such as animals, plants, bacteria, and minerals that are used to control pests and diseases in crops. They are considered eco-friendly alternatives to chemical pesticides.

3. **Identify the Microbe for Pest Control:**
- Among the various microbes used as biopesticides, we need to identify which one specifically targets butterfly caterpillars.

4. **Review the Options:**
- The options provided include various microorganisms. We need to evaluate which of these is known for its effectiveness against butterfly caterpillars.

5. **Select the Correct Microbe:**
- The correct answer is **Bacillus thuringiensis**. This bacterium is well-known for its use in biocontrol as it produces insecticidal proteins (cryoproteins) that are toxic to certain pests, including butterfly caterpillars.

6. **Conclusion:**
- Therefore, the microbe used for biocontrol of pest butterfly caterpillars is **Bacillus thuringiensis**.

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