In which of the following plants, pollen is released before the stigma becomes receptive in the same flower

Options

A. Allium
B. Colchicum
C. Datura
D. Solanum.

Answer

To solve the question, "In which of the following plants, pollen is released before the stigma becomes receptive in the same flower," we need to understand the concept of dichogamy and its types.

### Step-by-Step Solution:

1. **Understanding Dichogamy**:
- Dichogamy refers to the phenomenon where the male and female reproductive organs of a flower mature at different times. This helps in preventing self-fertilization.

2. **Types of Dichogamy**:
- There are two types of dichogamy:
- **Protandry**: This is when the stamens (male parts) mature and release pollen before the pistils (female parts) become receptive.
- **Protogyny**: This is when the pistils mature and become receptive before the stamens release pollen.

3. **Identifying the Condition**:
- The question specifically asks for a plant where pollen is released before the stigma becomes receptive, which corresponds to the protandry condition.

4. **Examples of Protandry**:
- One common example of a plant that exhibits protandry is the onion (Allium cepa). In onions, the stamens mature and release pollen before the stigma is ready to receive it.

5. **Conclusion**:
- Therefore, the correct answer to the question is that pollen is released before the stigma becomes receptive in the onion plant.

### Final Answer:
- The correct option is **option number 1: Onion (Allium cepa)**.