Pollination is the process in which pollen transfers from another to stigma from the same plant or flower to the same plant or different plant. Pollination occurs in two forms which are self and cross-pollination. This is the reproduction process in plants. This is done by transferring pollen grains through a pollinating agent or not.
Self-Pollination vs Cross-Pollination
The main difference between Self-pollination and Cross-pollination is Self-pollination occurs between two same plants or same individuals without any external agent for pollination, but Cross-pollination occurs between two different plants using a pollinating agent. The pollinating agent can be birds, insects, or wind. Cross-pollination occurs in most flowering species as compared to self-pollination.
Self-pollination is the sexual mode of reproduction in plants. Pollen grains are move from the anther to the stigma of the same plant. The fertilization process also happens due to the transfer of pollen grains. Gene uniformity is seen in self-pollination. There is no variation or difference in the plants or individuals.
Cross-pollination is the process in which the movement of pollen grains is from stigma to stigma of another plant. This process is mostly in the plants. Almost three-fourths of flowering plants do cross-pollination. This pollination needs an agent to carry pollen grains from one plant to another plant.
Comparison Table Between Self-Pollination and Cross-Pollination
| Parameters of Comparison | Self-Pollination | Cross-Pollination |
| Process | Same flower | Different flower |
| Proportion | One-fourth | Three-fourth |
| Pollinating Agent | Not required | Required |
| Increasing factor | Gene uniformity | Genetic variation |
| Gene poll | Decreases | Maintained |
| Amount of pollen | Limited | Large |
What is Self-Pollination?
Self-pollination is one type of pollination. It is considered the sexual mode of reproduction in flowering plants. The pollens move from one plant to the stigma of the same plant. Self-pollination is divided into two subcategories. Those categories are autogamy and geitonogamy. Autogamy is the process in which pollen moves from the stigma of the same flower.
Geitonogamy is the process in which the pollen grains move from the anther of the same flower. The pollinating agent is not required in this pollination as the whole process takes place in the same individual. The process can be seen in legumes. Peanut is an example of legumes. Genetic variations are not visible in self-pollination.
Uniformity of genes is a characteristic of self-pollination. They do not need more energy for production. They can grow anywhere. They do not need insects as a carrier of pollen grains. They can grow anywhere like Artic. This process is only visible in nearly one-fourth of plants. This process limits the variety of progeny.
This pollination is not dependent on anything, due to which it is easier to do their process on its own. The pollen grains are carried inside the same plant, due to which there is no wastage of pollen grains. The changes are not possible in the species.
What is Cross-Pollination?
This process is also one type of sexual reproduction in flowering plants. This process is widely observed in various species. This process requires pollination agents like birds or insects. The agents are needed to carry the pollen grains from one plant to another plant. This happens between two different people.
The process is dependent on these agents; otherwise, the process is not possible. Uniformity is absent in this type of pollination. Changes in the species are observed as the whole process occurs between two different individuals. Pollen grains move from the stamen of one plant to the stigma of another planet.
This process is also known as allogamy. The plants have no chance to undergo self-pollination. New genotypes are produced in this process. Cross-pollination brings genetic diversity. This also prevents depression of inbreeding. Inbreeding depression is the decrease in the population of particular species. The pole of the gene is maintained by the process of cross-pollination.
The process has an advantage as the plants do not do with the same flower, and every time they receive pollen grains from different plant saves them from becoming extinct. The species get saved as their genes are different. This pollination is done three-fourth of the flowering species.
Main Differences Between Self-Pollination and Cross-Pollination
- Self-pollination occurs between the same flower or same individual, but Cross-pollination occurs between different plants.
- Self-pollination happens in one-fourth of the flower species, but Cross-pollination happens in three-fourth of the flowering species.
- Self-pollination can occur without any agent, but Cross-pollination will require an agent.
- Genetic uniformity increases in self-pollination but genetic variation increases in cross-pollination.
- Gene pool gets reduced in this self-pollination, but Gene poll is very well maintained in the cross-pollination.
- Limited pollen is produced during self-pollination, but a large amount of pollen is produced in cross-pollination.
Conclusion
Peanut is an example of legumes. Genetic uniformity increases in self-pollination. The pollens move from one plant to the stigma of the same plant. They do not need insects as a carrier of pollen grains. Limited pollen is produced during self-pollination. The changes are not possible in the species.
The pollinating agent is not required in this pollination as the whole process takes place in the same individual. This process is only visible in nearly one-fourth of plants. Those categories are autogamy and geitonogamy. They can grow anywhere. This pollination is not dependent on anything, due to which it is easier to do their process on its own.
Cross-pollination brings genetic diversity. Genetic variation increases in cross-pollination.
This also prevents depression of inbreeding. Inbreeding depression is the decrease in the population of particular species. A large amount of pollen is produced in cross-pollination. Pollen grains move from the stamen of one plant to the stigma of another planet.
Inbreeding depression is the decrease in the population of particular species. The agents are needed to carry the pollen grains from one plant to another plant. The plants have no chance to undergo self-pollination. New genotypes are produced in this process.
References
- https://bsapubs.onlinelibrary.wiley.com/doi/abs/10.1002/j.1537-2197.1991.tb14511.x
- https://www.sciencedirect.com/science/article/pii/S1161030107000093