Pollination Basics — Part 1 | Wisconsin Pollinators

 

The Types Of Pollination

What Is Pollination?

Flower pollination is one of the crucial events in the life cycle of many flowering plants. When a pollen grain moves from the anther (male part) of a flower to the stigma (female part), pollination happens. This is the first step in a process that produces seeds, fruits, and the next generation of plants.

Pollination Vocabulary

Antler The part of the stamen where pollen is produced
Cross-pollination A type of pollination in which the pollen from the anther of a flower is transferred to the stigma of a flower of another plant
Filament The stalk that holds the anther and attaches it to the flower.
Nectary Nectaries are specialized nectar-producing structures of the flower
Ovary The enlarged basal portion of the pistil where ovules are produced.
Petal The parts of a flower that are often conspicuously colored
Pistil The ovule producing part of a flower. The ovary often supports a long style, topped by a stigma. The mature ovary is a fruit, and the mature ovule is a seed.
Self-pollination A type of pollination in which the pollen from the anther of the flower is transferred to the stigma of the same flower
Sepal The outer parts of the flower (often green and leaf-like) that enclose a developing bud.
Stamen The pollen producing part of a flower, usually with a slender filament supporting the anther.
Stigma The part of the pistil where pollen germinates.
Style This is the name for the stalk of the pistil. When pollen reaches the stigma, it begins to grow a tube through the style called a pollen tube, which will eventually reach the ovary. The style therefore acts as a buffer against pollen contamination, since only compatible pollen is able to grow a pollen tube.
Graphic showing labeled parts of a flower

Types of Pollination

Although all flowering plants rely on pollination for reproduction, there is a variation in how plants pollinate. There are two types of pollination: self-pollination and cross-pollination.

Self-Pollination

Self-pollination is the more basic type of pollination because it only involves one flower. This type of pollination occurs when pollen grains from the anther fall directly onto the stigma of the same flower. Although this type of pollination is simple and quick, it does result in a reduction in genetic diversity because the sperm and egg cells of the same flower share genetic information.

Cross-Pollination

Cross-pollination is a more complex type of pollination that involves the transfer of pollen from the anther of one flower to the stigma of a different flower. This type of pollination results in an increase in genetic diversity because the different flowers are sharing and mixing their genetic information to create unique offspring.

Cross-Pollination Strategies

Graphic showing cross-pollination

Cross-pollination is more complex than self-pollination because it requires the movement of pollen from one flower to another flower. There are several strategies that flowering plants utilize to move pollen from one flower to another including: wind, water, and animal pollination.

Animal Pollination

Pollination can be observed first hand by watching the movements of animal pollinators. Animal pollinators are organisms that travel from flower to flower and transfer pollen to each flower they visit. This type of pollination is very important because around 80% of all flowering plants and 75% of staple crop plants require animals to help complete the pollination process. Some common animal pollinators that you may have seen flying from flower to flower include bees, beetles, birds, flies, moths, bats, and butterflies.

Wind Pollination

Wind is commonly used to transport pollen long distances. Plants that use wind to transport pollen often have pollen grains that are small, lightweight, and smooth. These plants are also often found in large populations because this increases the chance of a pollen grain landing on a flower of the same species.

Water Pollination

Although this strategy is not common, some plants rely on water to transport their pollen to other flowers. Water transportation of pollen can involve rain water or waterways, such as streams.

Test your knowledge: Try the 'Parts of a Flower Identification' quiz.

Further Reading:

 Pollination — Part 2, Mechanisms of Pollination
 The Benefits of Pollen
 Host versus Nectar Plants: How It Works  Do Plants 'See'?
 Do Plants 'Breathe'?