Which of the following is not an application of genetic engineering in plants?

Options

A. Nitrogen fixation
B. DNA vaccines
C. Resistance to glyphosate
D. Production of insecticidal proteins in plants

Answer

To determine which of the following is not an application of genetic engineering in plants, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand Genetic Engineering**: Genetic engineering involves altering the genome of an organism, which can include adding or removing genes to obtain desired traits or benefits.

2. **Evaluate Each Option**:
- **Option 1: Nitrogen Fixation**: This is a natural process where certain bacteria convert atmospheric nitrogen into ammonia, which is then utilized by plants. It is not a result of genetic engineering.
- **Option 2: DNA Vaccines**: These are developed using genetic engineering techniques to create edible vaccines from plants, which can provide passive immunity. This is an application of genetic engineering.
- **Option 3: Resistance to Glyphosate**: Glyphosate is a herbicide that can inhibit photosynthesis. Genetic engineering is used to create plants that are resistant to glyphosate, making this an application of genetic engineering.
- **Option 4: Production of Insecticidal Proteins (Bt Toxin)**: The introduction of Bt toxin into crops (like Bt cotton) to provide resistance against pests is a well-known application of genetic engineering.

3. **Identify the Correct Answer**: Based on the evaluations, the only option that is not an application of genetic engineering in plants is **Nitrogen Fixation**.

### Final Answer:
The option that is not an application of genetic engineering in plants is **Nitrogen Fixation**.

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