What Does It Mean for a Plant to Self Pollinate?

Self-Pollination

• Self-pollinated plants are also called "self-fruitful." That means that they don't need the pollen of another plant, even a plant of the same variety, to set fruit. Self-pollinating plants produce pollen on the anthers, and that pollen is transferred either to the stigma of the same flower or to the stigma of another flower on the same plant.

Flowers of Self-Pollinating Plants

• Most self-pollinating plants have a flower structure that supports self-pollination. Some of these flowers never open. That means that the pollen of other flowers can't get to the stigma. Other self-pollinating flowers open only after they have been fertilized. Other self-pollinating flowers bury the stigma deep inside the flower or surround it closely by the anthers of the flower, making it unlikely for foreign pollen to reach the stigma. Because self-pollinating flowers are less likely to need insect pollinators, flowers also tend to be smaller and less showy.

Consequences

• The consequences of self-pollination include a more uniform progeny. Because all the genetic material in a self-pollinating plant is from a single parent, undesirable hybrids are less likely. This lack of diversity, however, makes the species as a whole less resilient and adaptable to changing environment. Some self-pollinating plants don't have to attract pollinators, so they spend less of the plant's resources on attracting pollinators and more on reproduction.

Self-Fruitful Plants

• Self-pollinated vegetables include beans, lettuce, endive, peas, tomatoes. Self-pollinating grains include wheat, rice, barley and oats. Most peaches, sour cherries, strawberries, grapes, raspberries and blackberries are self-pollinated. Some apple and pear varieties are self-pollinated, but they do not self-pollinate very well. If they are given another variety to perform some of the pollination, they bear more and better fruit.