The difference between pollination and fertilization is that in pollination, pollen is transferred from the male part of any plant to the female part of the plant while in fertilization, gamete from a male partner unites with the gamete from a female partner or pollen from the male part of flower combines with the eggs from the female part of the flower.
In the process of pollination, pollens are only transferred from one flower to another while in fertilization, male gamete or pollen from one flower unites with the egg or female gamete from another plant. Pollination occurs only in the flowering plants while the process of fertilization occurs in all the sexually reproducing organisms. The pollen tube is not formed in the process of pollination while during fertilization, a pollen tube is formed which transfers the male gametes of one flower to the female gametes or eggs of the other plants.
Pollination is an external phenomenon and occurs on the outer part of the plant. While fertilization is an internal mechanism and occurs inside the flowers. Pollination always takes place before fertilization. Pollination is further classified into two subtypes, i.e., self-pollination and cross-pollination while fertilization has no further subtypes. Transfer vectors are required for pollination. These transfer vectors pollen between anther and stigma (parts of flowers). Some examples of transfer vectors are wasps, honeybees, butterflies and moths. No such type of vector is required for fertilization.
Comparison Chart
| Basis | Pollination | Fertilization |
| Definition | It is a process in which pollen grains are transported from male organ of any flower to the female part of same or any other flower. | It is a process in which male and female gametes are fused (pollen with egg in case of plants) in any sexually reproducing organism. |
| Occurs in | It occurs only in the flowering plants. | It occurs in all the sexually reproducing organisms including plants and animals. |
| Need for each other | Fertilization may or may not occur after fertilization. | Pollination is mandatory for fertilization in plants. |
| Need for Pollen tube | Formation of the pollen tube is not necessary for this process. | A pollen tube is always needed for fertilization in plants. |
| The site at which the process occurs | It is an external phenomenon. It occurs on the outer part of a flower. | It is an internal phenomenon. It always takes place inside the flower. |
| Subtypes | It is further classified into two subtypes, i.e., self-pollination and cross-pollination. | It does not have further subtypes. |
| Need for transfer vector | A transfer vector is required for pollination. | No need of transfer vector for fertilization. |
What is Pollination?
Pollination is the process during which pollen is germinated on stigma. During pollination, pollen from male organs of a plant is transferred to the female organ of the same or different flower.
The male organ of the plant is called as another which produces the male gametes of the plant called pollen which have the male genetic material. Anthers are located on stamen which is actually the tip of a stalk. The female organ of the plant is known as stigma, which receives the pollen from the male organ of the flower. This stigma is located on ‘pistil’ which is the tip of the female organ of the flower. Thus sperm cells are sent to the ovary which has female gametes of the plant called as ovules or eggs.
Pollination is divided into two types, i.e., self-pollination and cross-pollination.
Self-pollination is the type of pollination in which female part of the flower or stigma receives the pollen from the male part of the same plant. Common examples of this type of pollination can be given as thaliana, Capsella rubella, Arabidopsis and Bulbophyllum bicoloratum.
Self-pollination is further classified into two types, i.e., autogamy and geitonogamy. In autogamy, pollen grains are transferred within the same flower from the male part of the flower to the female part. While in geitonogamy, pollen grains are transferred from the male organ of a flower to the female organ of any other flower located on the same plant.
What is Fertilization?
Fertilization is a process during which a sperm unites with an egg. It occurs after pollination in the plants. Each male and female gamete consists of half of their genetic material which unites to form a new plant.
When pollen grains from the male organ of the flower touch the stigma, a tiny tube is made along with the pollen. This tube is anchored within another tube-like structure known as the style of the female pistil. This tube expands itself to the opening of the ovary, where the pollen grains are collected. Female gametes of the plants or eggs are present within the ovary. When the union of the pollen with egg occurs, the fertilization occurs, and the egg is now developed into a seed (zygote). The process of fertilization occurs in the deep inner part of the flower.
Double fertilization
This process takes place only in the angiosperm plants. In this process, two sperms are used. One sperm or pollen grain fertilizes the female gamete or egg, and a zygote is formed (syngamy). While the other pollen grain unites with the secondary nucleus to generate a triploid nucleus. It is also known as the primary endosperm nucleus.
Key differences
- In pollination, pollen grains are only transferred from the male organ of a flower to the female organ of the same or any other flower while fertilization is a process during which fusion of male and female gametes occurs.
- The process of pollination occurs only in the flowering plants while the process of fertilization occurs in all the sexually reproducing organisms.
- Pollination occurs on the outer part of a flower while fertilization occurs in the inner part of a flower.
- Formation of style is mandatory for pollination but not for fertilization.
- Fertilization always takes place after pollination in plants. Pollination is necessary for fertilization in plants, but fertilization is not necessary for pollination.
- A transfer vector is needed for pollination but not for fertilization.
- Pollination is further classified into two types, i.e., self-pollination and cross-pollination while fertilization does not have further subtypes.
Conclusion
Pollination and fertilization are commonly used terms in the study of plants. Both are important for the reproduction of plants and often they are confused. It is compulsive to know the difference between both of them. In the above article, we learned the clear differences between pollination and fertilization.