Phytochrome was discovered by

Options

A. W. Went
B. Garner and Allard
C. F.F. Blackman
D. Borthwick and Handricks

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the discovery of phytochrome, which is a pigment involved in plant responses to light.

2. **Identifying the Options**: The options provided are:
- A) W. Wendt
- B) Gardner and Allard
- C) F. F. Blackman
- D) Bothwick and Henricks

3. **Analyzing Each Option**:
- **Option A (W. Wendt)**: This option is not related to the discovery of phytochrome. Wendt is known for other contributions in plant biology.
- **Option B (Gardner and Allard)**: They are recognized for their work on photoperiodism, which is the response of plants to the length of day and night, but not for discovering phytochrome.
- **Option C (F. F. Blackman)**: Blackman is known for the Law of Limiting Factors, which relates to photosynthesis and plant growth but does not pertain to phytochrome.
- **Option D (Bothwick and Henricks)**: This option is correct. Bothwick and Henricks, along with Parker, discovered phytochrome in 1940 using the Balsillie Spectrograph.

4. **Conclusion**: The correct answer to the question "Phytochrome was discovered by" is **D) Bothwick and Henricks**.

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