Flowering plants have developed many devices to discourage self - pollination and to encourage cross - pollination except

Options

A. Dicliny
B. Dichogamy
C. Homogamy
D. Self Incompatibility

Answer

To solve the question regarding the devices developed by flowering plants to discourage self-pollination and encourage cross-pollination, we need to analyze the options provided and identify which one does not serve this purpose.

### Step-by-Step Solution:

1. **Understanding Self-Pollination and Cross-Pollination**:
- Self-pollination occurs when pollen from the anther of a flower fertilizes the ovule of the same flower.
- Cross-pollination occurs when pollen from one flower fertilizes the ovule of another flower, promoting genetic diversity.

2. **Identifying Outbreeding Devices**:
- Flowering plants have developed several mechanisms to prevent self-pollination and promote cross-pollination. These mechanisms are known as outbreeding devices.

3. **Key Outbreeding Devices**:
- **Dichogamy**: This is when the anther and stigma mature at different times, preventing self-pollination.
- **Dichlincy**: This refers to unisexual flowers, where either male or female reproductive organs are present, thus preventing self-pollination.
- **Self-Incompatibility**: This is a mechanism where pollen from the same plant is recognized and rejected by the stigma, preventing fertilization.

4. **Identifying the Incorrect Option**:
- **Homogamy**: This is the condition where the anther and stigma mature at the same time, which increases the likelihood of self-pollination rather than discouraging it. Therefore, it does not serve as an outbreeding device.

5. **Conclusion**:
- The option that does not serve as a device to discourage self-pollination and encourage cross-pollination is **Homogamy**.

### Final Answer:
**Homogamy** does not serve as a device to discourage self-pollination and encourage cross-pollination.