Which bateria is used as biopesticide first on the commerical scale in the world

Options

A. bacillus thuringiensis
B. E.coli
C. Pseudomones aeruginosa
D. Agrobacterium tumefaciens

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks which bacteria was first used as a biopesticide on a commercial scale in the world.

2. **List the Options**: The options provided are:
- A) Bacillus thuringiensis
- B) E. coli
- C) Pseudomonas aeruginosa
- D) Agrobacterium tumefaciens

3. **Analyze the Options**:
- **Bacillus thuringiensis**: This is a soil bacterium known for producing a toxin (endotoxin) that is effective against certain insects. It produces cryoproteins that become activated in the alkaline pH of an insect's gut, leading to the insect's death. This bacterium is widely recognized as a biopesticide.
- **E. coli**: Primarily used in genetic engineering and not as a biopesticide.
- **Pseudomonas aeruginosa**: Also primarily used in genetic engineering and not recognized as a biopesticide.
- **Agrobacterium tumefaciens**: Known for its role in plant genetic engineering and as a plant vector, but not used as a biopesticide.

4. **Determine the Correct Answer**: Based on the analysis, **Bacillus thuringiensis** is the only bacterium among the options that is recognized for its use as a biopesticide on a commercial scale.

5. **Conclusion**: The correct answer to the question is **A) Bacillus thuringiensis**.

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