Which of the following is not a growth promoting activity of plant growth regulators ?

Options

A. Cell division
B. Pattern formation
C. Seed germination
D. Abscission

Answer

To determine which of the following options is not a growth-promoting activity of plant growth regulators, we need to analyze each option provided:

1. **Cell Division**: Plant growth regulators, particularly auxins and cytokinins, promote cell division. Therefore, this is a growth-promoting activity.

2. **Pattern Formation**: Plant growth regulators are involved in the regulation of developmental processes, including pattern formation in plants. This is also a growth-promoting activity.

3. **Seed Germination**: Certain plant growth regulators, such as gibberellins, play a crucial role in promoting seed germination. Hence, this is a growth-promoting activity as well.

4. **Abscission**: Abscission refers to the process of shedding leaves, flowers, or fruits from a plant. This process is generally considered a growth-inhibiting activity rather than a promoting one, as it involves the loss of plant parts rather than their growth.

Based on this analysis, the correct answer is **Abscission**.

### Step-by-Step Solution:
1. **Identify the Options**: The options provided are cell division, pattern formation, seed germination, and abscission.

2. **Analyze Each Option**:
- Cell Division: Promoted by growth regulators.
- Pattern Formation: Involves growth regulation.
- Seed Germination: Supported by growth regulators.
- Abscission: Involves shedding, not promoting growth.

3. **Determine the Non-Growth Activity**: Among the options, abscission is the only one that does not promote growth.

4. **Conclude the Answer**: The answer to the question is abscission.