Bacterium commonly used in plant genetic engineering is

Options

A. E. coli
B. Agrobacterium
C. Mycobacterium
D. Rhizobium

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the bacterium commonly used in plant genetic engineering.

2. **Consider the Options**: The options provided are:
- E. coli
- Agrobacterium
- Mycobacterium
- Rhizobia

3. **Recall Relevant Information**:
- E. coli is primarily used in molecular cloning and not specifically in plant genetic engineering.
- Mycobacterium is known for its role in human diseases and is not used in plant genetic engineering.
- Rhizobia are involved in nitrogen fixation in legumes but are not typically used for genetic engineering.

4. **Focus on Agrobacterium**:
- Agrobacterium tumefaciens is a well-known bacterium that has the unique ability to transfer DNA to plant cells. This property has been harnessed for genetic engineering purposes.
- It has been utilized since the early 1980s to create transgenic plants by inserting desired genes into the plant genome.

5. **Conclusion**: Based on the information, the bacterium commonly used in plant genetic engineering is **Agrobacterium**.

**Final Answer**: Agrobacterium

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