Have you ever been surprised why bees are attracted to flowers? Blooms seem gorgeous and are fragrant, but there is a reason behind this — flowers actually aid plants to reproduce. Flowering plants have seeds and they carry the genetic information of the parents and develop into a new plant.
What is Pollination?
Pollination is a procedure where pollen grains are taken from an anther, which is the male portion of a flower and transferred to the flower’s female part called the stigma. In order for pollination to be successful, the pollen grains must be transferred from the same species of flower as the flowers being pollinated.
Process of Pollination
The process of pollination begins when the pollen grains from the respective flowers rest on the stigma and create a pollen tube with the style length, which connects both the stigma and ovary. After the completion of the pollen tube, the pollen grain starts transporting sperm cells from the grain to the ovary.
Later the process of fertilisation in plants will take place when the sperm cells will reach the ovary and egg cells. The seed is then freed from the parent plant and makes it able to grow into a plant and continue the reproductive cycle with the use of the pollination process.
Types of Pollination
All plants having flowers fully rely on pollination techniques for reproduction. There are 2 forms of pollination — Self Pollination and Cross-Pollination
Self Pollination
This sort of pollination is referred to as primary pollination because it involves only a single flower. When pollen grains fall directly from the anther into the stigma of the flower, this is known as self-pollination. Because this process is straightforward and quick, it results in a reduction in genetic diversity, as the sperm and egg cells of the flower share some genetic information with one another.
Advantages and Disadvantages of Self-pollination
The process of self-pollination ensures that recessive characters are not produced.
When compared to cross-pollination, there is very little wastage of the pollen grains.
Because there is no variation in the genes during the process of self-pollination, the purity of the race is maintained.
In self-pollination, there is no involvement of external factors such as wind, water, or other pollinating agents, which makes it a more efficient method.
With self-pollination, even a tiny amount of pollen grains produced by plants has a high success rate in pollination, ensuring that even a small amount of pollen grains produced by plants is pollinated.
Disadvantages
The primary disadvantage of self-pollination is that there is no cross-pollination of genetic material. As a result, the vigour and vitality of the race are diminished.
The immune system of the offspring is weakened as a result of the mating.
Cross-Pollination
It refers to a complicated method of pollination that permits pollen grains to be transferred from the anther of one flower to the stigma of another flower with the use of a pollen transfer agent. Due to the fact that various flowers will share and combine their genetic material in order to produce unique offspring, this strategy will result in an increase in genetic variety.
The Different Types of Cross-Pollination
Biological and abiotic agents such as animals, birds, wind, insects, water, and other agents that act as pollinators are required to carry out the process of cross-pollination.
Pollination by Wind-
There are only a few flowers that are pollinated by the wind, and their characteristics include greenish, tiny, and odourless blossoms. Because these flowers do not attract pollinators, their energy is not utilised to produce vibrant petals like those found in other flowers. This sort of pollination occurs most frequently when plants lack flowers that contain nectar as well as other characteristics such as inconspicuousness. The male reproductive portions of Anemophilous flowers have a tendency to produce vast quantities of pollen, while the stigma, which is the female reproductive component of a flower, is very large, sticky, and feathery, and it can reach completely outside the bloom in some cases. As a result, the pollen has a greater chance of reaching them.
Wind-pollinated plants include the coconut, palm, maize, grasses, and all gymnosperms, which are the most common types of flowering plants.
You must have seen that your automobile is completely covered with a yellow film in the spring; this is due to pollen being transported by the wind during the pollination process.
Pollination by Animals –
Animals have a vital part in the reproduction of plant species. They aid in the spreading of seeds. Following the consumption of a plant’s fruit by an animal, the animal relocates to a new area. This movement aids in the dispersal of seeds, which results in the establishment of new plants in new sites.
Artificial Pollination – Anthropophily
Human beings are responsible for artificial pollination. Anthropophily is a term used to describe this process. The artificial method of pollination is used when there are difficulties in the pollination process due to abiotic or biotic agents. This method involves dispersing pollen grains across the female flowers. Techniques of hybridization are also employed in this procedure.
Advantages and Disadvantages In the case of cross-pollination
Advantages
- The seeds that are created have a lot of vigour and vitality.
- Cross-pollination is a process by which all unisexual plants can reproduce and create offspring.
- As a result of genetic recombination, the recessive traits in the lineage are eradicated from the population.
- The immune system of the offspring is strengthened as a result of this procedure against illnesses and other environmental variables.
- Cross-pollination is responsible for the introduction of new genes into a sequence of species, and this is mostly owing to the fertilisation of gametes from genetically distinct populations.
Disadvantages
There is a significant amount of pollen grain waste throughout this operation.
Because of genetic recombination that occurs during meiosis, there is a possibility that desirable characteristics could be eliminated and undesirable characteristics will be added to offspring.
Conclusion
Pollination is a vital component of plant reproduction and development. During pollination, pollen from the male component of the plant i.e the anther of a flower brushes or drips onto a pollinator. The pollinator then transports the pollen to another flower, where the pollen comes in contact with the female part i.e the stigma of the flower. Later on, the fertilised bloom bears fruit and produces seeds.