Nif-genes are represented by a cluster of 17 genes and their transfer is carried out through

Options

A. E.coli
B. Agrobacterium
C. Aerobacter
D. Pseudomonas

Answer

**Step-by-Step Solution:**

1. **Understanding Nif Genes**: Nif genes are a cluster of 17 genes that play a crucial role in nitrogen fixation. They are found in certain bacteria, which can be free-living or symbiotic.

2. **Identifying the Role of Nif Genes**: These genes are essential for converting atmospheric nitrogen into a form that plants can use, which is vital for plant growth and agriculture.

3. **Gene Transfer Mechanism**: To transfer Nif genes into plants, a suitable vector is required. The most commonly used vector for gene transfer in plants is the Ti-plasmid.

4. **Source of Ti-plasmid**: The Ti-plasmid is found in the bacterium Agrobacterium tumefaciens. This bacterium is known for its ability to transfer DNA into plant cells.

5. **Incorporating Nif Genes into Ti-plasmid**: The Nif genes can be inserted into the Ti-plasmid. This modified Ti-plasmid can then be used to introduce the Nif genes into the target plant cells.

6. **Conclusion**: Therefore, the transfer of Nif genes is carried out through Agrobacterium tumefaciens, utilizing its Ti-plasmid.

**Final Answer**: The transfer of Nif genes is carried out through Agrobacterium tumefaciens.

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