In the process of cross pollination, the pollen is transferred from one plant to another by a pollinator, such as an insect, or by the wind. In self pollination, the plant’s stamen sheds pollen directly onto its own stigma.
Which plants self-pollinate?
Most plants use cross pollination. Those that use insects as pollinators tend to have brightly colored flowers and an attractive scent. Those that are pollinated by the wind have long stamens and pistils with small or no petals.
Plants that use self pollination, such as peanuts, tend to have smaller flowers. Some plants that cross pollinate are also capable of self pollination if cross pollination is unsuccessful. These include peas, orchids and sunflowers.
Examples of plants that use insects for cross-pollination include apples, plums, pears, raspberries, blackberries, blackcurrants, strawberries, runner beans, pumpkins, daffodils, tulips, heather, lavender, and most flowering plants.
Examples of plants that use wind for cross pollination include grasses, catkins, dandelions, maple trees, and goat’s beard.
Examples of self-pollinating plants include wheat, barley, oats, rice, tomatoes, potatoes, apricots and peaches. Many plants that are capable of self-pollinating can also be cross pollinated.
Advantages and Disadvantages
Cross pollination is advantageous because it allows for diversity in the species, as the genetic information of different plants are combined. However, it relies on the existence of pollinators that will travel from plant to plant.
Self pollination leads to more uniform progeny, meaning that the species is, for example, less resistant as a whole to disease. However, it does not need to expend energy on attracting pollinators and can spread beyond areas where suitable pollinators can be found.
- Wikipedia: Pollination
- Wikipedia: Self-pollination
- Self-Pollination - McGraw Hill
- Pollination - Biology of Plants
- RHS Plants for Pollinators - Royal Horticultural Society
- 5 Early Season Plants which Attract Pollinators to your Garden - Eartheasy
- Seeds & Fruits Dispersed By Wind - Wayne's Word
- Self-pollination - The Agricos