Bacterium commonly used in plant genetic engineering is

Options

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

Answer

**Step-by-Step Solution:**

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

2. **Identifying the Key Bacterium**: The bacterium that is widely recognized for its role in plant genetic engineering is Agrobacterium tumefaciens. This bacterium is often referred to as a "natural genetic engineer" because it has the ability to transfer genetic material to plant cells.

3. **Mechanism of Action**: Agrobacterium tumefaciens has a specific plasmid known as the Ti-plasmid (Tumor-inducing plasmid). Within this plasmid, there is a segment called T-DNA (Transfer DNA), which is responsible for causing tumors in plants.

4. **Genetic Engineering Process**: In the context of genetic engineering, scientists can manipulate Agrobacterium tumefaciens by removing the T-DNA and replacing it with desired genes (genes of interest). When the bacterium infects the plant, it transfers this modified T-DNA into the plant's genome, allowing for the introduction of new traits.

5. **Conclusion**: Based on the information provided, the correct answer to the question is Agrobacterium tumefaciens, as it is the bacterium commonly used in plant genetic engineering.

**Final Answer**: Agrobacterium tumefaciens

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