What is the significance of pollen-stigma interaction?

Explanation

### Step-by-Step Solution:

1. **Definition of Pollen-Stigma Interaction**:
Pollen-stigma interaction refers to the process that occurs when a pollen grain lands on the stigma of a flower. This interaction is crucial for the successful fertilization of flowering plants.

2. **Chemical Dialogue**:
Upon landing on the stigma, a chemical dialogue begins between the pollen grain and the stigma. Both the pollen grain and the stigma release specific chemicals that facilitate this interaction.

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