Polyethylene glycol method is used for

Options

A. Energy production from sewage
B. Gene transfer without a vector
C. Seedless fruit production
D. Biodiesel production

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the application of the polyethylene glycol (PEG) method. We need to identify which of the given options correctly describes its use.

2. **Analyzing the Options**:
- **Option A: Energy production from sewage**:
- Sewage can be converted into energy through anaerobic digestion, but this process does not involve polyethylene glycol. Therefore, this option is incorrect.

- **Option B: Gene transfer without a vector**:
- Polyethylene glycol is known to facilitate the uptake of DNA into plant protoplasts in a process called chemical-mediated gene transfer. This method allows for gene transfer without the need for a vector. Hence, this option is correct.

- **Option C: Seedless fruit production**:
- Seedless fruit production, or parthenocarpy, does not involve polyethylene glycol. This process is related to the natural development of fruits without fertilization. Thus, this option is incorrect.

- **Option D: Biodiesel production**:
- Biodiesel is produced through the transesterification of oils and fats, and polyethylene glycol is not involved in this process. Therefore, this option is also incorrect.

3. **Conclusion**: After analyzing all the options, the correct answer is **gene transfer without a vector**, as polyethylene glycol is specifically used in this context.

### Final Answer:
The polyethylene glycol method is used for **gene transfer without a vector**.

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