Which one is short day plant ?

Options

A. Brassica campestris
B. Raphanus sativus
C. Glycine max
D. Papaver somniferum.

Answer

**Step-by-Step Solution:**

1. **Understand the Definition of Short Day Plants:**
Short day plants are those that flower when the duration of daylight is shorter than a certain critical length. They require a longer period of darkness to initiate flowering.

2. **Identify the Characteristics of Short Day Plants:**
- They need longer nights (darkness) and shorter days (light) to trigger the flowering process.
- Examples of short day plants include soybeans, rice, and tobacco.

3. **Analyze the Given Options:**
The options provided are:
- Brassica canfistris
- Raffinus sativus
- Glycine max
- Papaver somniferum

4. **Determine the Flowering Requirements of Each Option:**
- **Brassica canfistris**: This is a long day plant.
- **Raffinus sativus**: This is also a long day plant.
- **Glycine max**: This is a short day plant (commonly known as soybean).
- **Papaver somniferum**: This is a long day plant.

5. **Conclusion:**
Among the options, **Glycine max** is the only short day plant.

**Final Answer:** Glycine max (soybean) is the short day plant.

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