Plants avoid incest
Genetic diversity has not failed to benefit any living being apart from some exception. Even plants benefit from the diversity which is why it has developed a method to avoid self pollinating. Many plants have both male and female organs which mean that they are hermaphroditic. It makes it easy to self-pollinate. Well to avoid this, plants such as petunias and tobacco plants, have advanced to develop what scientists call it the “self-incompatibility” strategy.
In this strategy, some plants can identify their own pollen once it has entered the female reproductive organ (called the “pistil”) and destroy it before fertilization occurs using a toxin called S-RNase. The S-RNase is produced even when genetically diverse pollen has entered the pistil but the plant avoids the destruction of possible pollen by withholding the toxin until it has recognized the pollen as either well-matched or mismatched.