How do plants prevent self-pollination?
Written by
Julia Anderson
Reviewed by
Prof. Martin Thorne, Ph.D.Plants avoid self-pollination by employing complex mechanisms that ensure genetic diversity and prevent inbreeding. These mechanisms result in cross-pollination between dissimilar flowers. Self-pollination will reduce the genetic diversity of the seed and harm future generations. The plants have developed great adaptations to counteract this, ensuring healthy reproduction; the garden tomatoes, apples, and so on use these means.
Temporal Separation
- Dichogamy: Male/female organs mature at different times
- Protandry: Anthers release pollen before stigmas become receptive
- Protogyny: Stigmas receptive before pollen release
Physical Barriers
- Herkogamy: Spatial separation of anthers and stigma
- Recurved styles position stigmas away from pollen
- Stamens positioned below or above stigma level
Self-incompatibility means chemical recognition processes. Flowers identify and reject their pollen. The specially made proteins on the stigma surfaces recognize the genetic affinity of the pollen. The compatible pollen sends acceptance messages. This molecular basis prevents inbreeding depression of the offspring. Apples and cherries utilize it to develop their gene pools effectively.
Monoecious plants produce distinct male and female flowers. In corn, there are tassels (male) and the ears (female). Cucumber produces separate male and female flowers. The separation of forces prevents cross-pollination between flowers. Insects or wind transfer the pollen from one flower to another.
These mechanisms ensure that the benefits of a diverse genetic pool are upheld. Cross-pollination leads to the offspring exhibiting hybrid vigor. The plants show increased resistance to diseases. They are better equipped to adjust to changes in their environment. There's a higher rate of fruit production. All of this leads to the betterment of your garden, thanks to these natural systems.
Gardeners can assist these natural processes by by planting several varieties to facilitate cross-pollination with partners. Include nearby pollinator-friendly flowers. Avoid using pesticides during the blooming period. Determine the type of pollination required by your plants. These things will increase the fruit production of your garden.
Read the full article: Understanding Flower Reproductive Parts and Functions
