Which one of the following bacteria has found extensive use in genetic engineering work in plants?

Options

A. Clostridium species
B. Xanthomonas citri
C. Bacillus coagulants
D. Agrobacterium tumefaciens

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks which bacterium is extensively used in genetic engineering work in plants. We have four options to evaluate.

2. **Evaluating Each Option:**
- **Option A: Clostridium species**
- Clostridium is known for causing diseases like botulism and is not primarily associated with genetic engineering in plants.

- **Option B: Xanthomonas citri**
- Xanthomonas citri is important in the food industry but does not play a significant role in plant genetic engineering.

- **Option C: Bacillus coagulans**
- Bacillus coagulans is involved in medicinal applications, particularly in antibiotic production, but is not used in plant genetic engineering.

- **Option D: Agrobacterium tumefaciens**
- Agrobacterium tumefaciens is known as "nature's genetic engineer." It plays a crucial role in introducing foreign genes into plant cells, facilitating the creation of transgenic plants.

3. **Identifying the Correct Answer:**
Based on the evaluations, the bacterium that has found extensive use in genetic engineering work in plants is **Agrobacterium tumefaciens**.

4. **Final Answer:**
The correct answer is **Agrobacterium tumefaciens**.

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