Which of the following enhances or induces fusion of protoplasts?

Options

A. IAA and kinetin
B. IAA and gibberellins
C. Sodium chloride and potassium chloride
D. Polyethylene glycol and sodium nitrate

Answer

To determine which substance enhances or induces the fusion of protoplasts, we can follow these steps:

### Step 1: Understand Protoplasts
- **Definition**: Protoplasts are plant cells that have had their cell walls removed, leaving only the cell membrane and cytoplasm.
- **Importance**: Protoplasts are crucial for various biotechnological applications, including genetic engineering and hybridization.

### Step 2: Identify the Agents
- The options provided are:
1. IAA
2. Kinetin
3. Zevalin
4. Sodium Chloride
5. Potassium Chloride
6. Polyethylene Glycol
7. Sodium Nitrate

### Step 3: Analyze Each Option
- **IAA (Indole-3-Acetic Acid)**: A plant growth hormone (auxin) that regulates growth but does not induce protoplast fusion.
- **Kinetin**: Another plant growth hormone that promotes cell division but is not known for protoplast fusion.
- **Zevalin**: Not commonly associated with protoplast fusion.
- **Sodium Chloride & Potassium Chloride**: Salts that may affect osmotic balance but do not induce protoplast fusion.
- **Polyethylene Glycol (PEG)**: A chemical that is widely recognized for enhancing protoplast fusion by facilitating the adhesion of protoplasts.
- **Sodium Nitrate**: While it has various roles in plant nutrition, it is not primarily known for inducing protoplast fusion.

### Step 4: Conclusion
- The most effective agents for inducing protoplast fusion are **Polyethylene Glycol (PEG)** and **Sodium Nitrate**. However, PEG is the most commonly used agent in laboratory settings for this purpose.

### Final Answer
The correct option that enhances or induces the fusion of protoplasts is **Polyethylene Glycol (PEG)**.

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