Bt cotton has been produced by

Options

A. In situ hybridisation of Bt gene
B. Northern blotting of Bt gene
C. Cloning of Bt gene
D. Southern blotting of Bt gene

Answer

**Step-by-Step Solution:**

1. **Understanding Bt Cotton**: Bt cotton is a genetically modified organism (GMO) that has been engineered to express a gene from the bacterium Bacillus thuringiensis (Bt). This gene produces a protein that is toxic to certain pests, particularly the cotton bollworm.

2. **Identifying the Source**: The source of the gene used in Bt cotton is Bacillus thuringiensis. This bacterium produces a toxin that is harmful to specific insects that feed on cotton plants.

3. **Gene Transfer Process**: To create Bt cotton, scientists isolate the gene responsible for producing the Bt toxin. This gene is then inserted into the cotton plant's genome.

4. **Cloning the Gene**: The process of cloning involves making multiple copies of the Bt gene. This is necessary to ensure that the cotton plant can produce enough of the toxin to deter pests effectively.

5. **Final Product**: The genetically modified cotton plant, which now contains the Bt gene, is referred to as Bt cotton. This cotton is resistant to bollworm damage, leading to higher yields and reduced pesticide use.

6. **Conclusion**: The correct answer to the question is that Bt cotton has been produced by cloning the gene from Bacillus thuringiensis.

**Final Answer**: Bt cotton has been produced by cloning.

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