Garner and Allard are related with

Options

A. Photolysis
B. Phototropism
C. Photo-periodism
D. Photophosphorylation

Explanation

To solve the question regarding the relationship of Garner and Allard, we will analyze the options provided and identify the correct phenomenon they are associated with.

### Step-by-Step Solution:

1. **Understanding the Options**: The question presents four options related to different biological phenomena:
- Photolysis
- Phototropism
- Photoperiodism
- Photophosphorylation

2. **Analyzing Photolysis**:
- Photolysis refers to the splitting of water molecules during the light reaction of photosynthesis, producing oxygen and electrons.
- **Conclusion**: Garner and Allard are not associated with photolysis.

3. **Analyzing Phototropism**:
- Phototropism is the growth of plants in response to light direction, primarily influenced by the hormone auxin.
- This phenomenon was studied by Charles Darwin and his son, but it is not related to Garner and Allard.
- **Conclusion**: Garner and Allard are not associated with phototropism.

4. **Analyzing Photoperiodism**:
- Photoperiodism is the response of plants to the relative lengths of daylight and darkness, which affects their flowering and growth.
- Garner and Allard conducted significant research on this phenomenon in 1920, particularly with the Maryland Mammoth variety of tobacco. They demonstrated that controlling light exposure can induce flowering.
- **Conclusion**: Garner and Allard are indeed associated with photoperiodism.

5. **Analyzing Photophosphorylation**:
- Photophosphorylation is the process of ATP formation during the light reactions of photosynthesis, involving the electron transport chain.
- This process is unrelated to the work of Garner and Allard.
- **Conclusion**: Garner and Allard are not associated with photophosphorylation.

6. **Final Answer**: Based on the analysis, the correct answer is that Garner and Allard are related to **Photoperiodism**.