Which of the following is used in developing transgenic plants?

Options

A. Rhizopium sp
B. Agrobacterium tumefaciens
C. Bacillus subtilis
D. Pseudomonas denitry ficans

Answer

To solve the question "Which of the following is used in developing transgenic plants?", we will analyze each option provided and determine which organism is most commonly used for this purpose.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- A) Rhizobium species
- B) Agrobacterium
- C) Bacillus subtilis
- D) Pseudomonas gentrificans

2. **Understanding Transgenic Plants**: Transgenic plants are genetically modified organisms (GMOs) that have had foreign genes inserted into their genome. This process often involves the use of specific bacteria that can transfer DNA into plant cells.

3. **Analyze Each Option**:
- **A) Rhizobium species**: This bacterium is primarily associated with nitrogen fixation in leguminous plants and forms nodules on roots. It is not typically used for developing transgenic plants.
- **B) Agrobacterium**: Specifically, *Agrobacterium tumefaciens* is known for its ability to transfer a part of its DNA (T-DNA) into the plant genome. This makes it a key tool in the development of transgenic plants.
- **C) Bacillus subtilis**: This bacterium is known for its role in soil health and as a biocontrol agent against pathogens, but it is not used for the genetic modification of plants.
- **D) Pseudomonas gentrificans**: Similar to Bacillus subtilis, this bacterium is involved in various ecological roles but does not play a role in developing transgenic plants.

4. **Conclusion**: Based on the analysis, the organism most commonly used in developing transgenic plants is **B) Agrobacterium**.

### Final Answer:
The correct answer is **B) Agrobacterium**.

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