Aim: To control pollination through emasculation, tagging, and bagging.
Plants with large bisexual flowers
Emasculation is defined as the process of artificial hybridization in which female flowers' stamens are separated from bisexual flowers in order to avoid self-fertilization. Much before the anthers mature, this process takes place. Emasculation is the method of extracting anthers from bisexual flowers before they mature. After that, the emasculated flower is bagged to keep any unwanted pollination.
This method aids in the development of flowers that have the desired characteristics. It is essential to have knowledge of flower structure, fertilization, flower physiology, and fertilization for this.
Choose a flower bud and open it to extract the stamens. This is referred to as emasculation. It is the female parent vine, so make a note of it.
The plant is then wrapped in a plastic bag to keep unwanted pollen from pollinating it.
Bring it in contact with the anther of a male plant that has the desired traits. The pollen should be dusted on the stigma's surface.
Cover the pollinated flower with a polythene bag and mark it with the seed parent's name as soon as possible.
Pollination is a plant reproduction process in which pollen grains are transferred from the anther to the stigma. There are two forms of pollination:
Pollen and stigma must be compatible for pollination to be effective. Pollen grains can be rejected due to incompatibility. This is unfavorable, especially in commercial crop production. Artificial hybridization was established as a result.
For successful pollination and fertilization, pollen-stigma compatibility is important. When compatible pollen is accepted by the pistil, fertilization events begin, while incompatible pollen is rejected. The ability of a pistil to recognize its pollen is the product of long-term pollen-pistil interaction as well as chemicals released by pollen.
Hybridization proceeds in two steps:
Hybridization is a form of selective breeding, as we all know. Anthers must be removed from a bisexual flower before pollen grains can be released. Emasculation is the process of removing an Anther with forceps. This phase is not expected in the case of unisexual flowers.
Bagging is an essential component of all pollination operations. Until anthesis, the female (receptive) flowers must be protected to protect the stigma from contamination before the desired pollen can be added. Usually, the bag is made of semi-transparent treated paper. By securing the bag over the shoot's tip, the flowers can be secured. To make the bags more comfortable, they must be tightly fitted and fixed.
Bagging is a way of shielding emasculated flowers from unwanted pollen grains. Despite the fact that the flower is obscured by a bag, it achieves receptivity. Bagging is performed before the flowers open in unisexual flowers.
The female flower is absolutely covered from contamination thanks to emasculation and bagging.
The desired pollen is dusted on the stigma once the flower has achieved stigma receptivity. This has been resealed in preparation for future developments.
As a result, artificial hybridization ensures that the correct form of pollen is transferred to the flower's stigma. Furthermore, there is a fair possibility of fertilization. This method allows for the production of a wide range of crop strains while also improving the quality of crops with desirable characters.
Emasculation – Emasculation is the process of artificial hybridization where the pollen and anthers of the flower are separated to prevent self-pollination.
Bagging – Bagging involves covering the emasculated flower with a bag to prevent pollinating agents from reaching it.
The stigma of emasculated flowers can be dusted with pollen of the desired kind.
Artificial hybridization is therefore possible.
Control-pollination is a plant enhancement technique that produces progeny with genes from each of two established parent plants. Transferring pollen from one plant to the receptive female reproductive organs of another plant while removing all other pollen is known as control pollination.
Control-pollination is necessary to:
To establish and maintain a pedigreed breeding population, control pollination is required.
In order to control inbreeding in the breeding population
Hybridization and back-cross between species must be done.
Control-pollination techniques are specifically engineered and managed to generate seeds with greater genetic trait and genetic uniformity than naturally pollinated seeds, as well as eliminating pollen contamination issues.
Pollination in plants can happen in two ways, self-pollination that happens within the same plant and cross-pollination that happens across the plants. Insects, water, wind etc, which facilitates pollination in plants are known as pollinating agents. However, insects were the first pollinating agents that helped the plants from their primitive stages. Pollination in plants plays a key role in the sexual reproduction of plants. It benefits not only plants but also human beings and animals by providing various fruits that we eat and flowers we use to decorate. Even today, many tribals who live in forests have fruits as their main source of nutrition. Artificial hybridization techniques have improved these chances of utilizing the plants much better. The flowers produced through pollination are a key source in the perfume industry and horticulture industry. Flowers play an important role also in the soap manufacturing and talcum powder industries. With the rise of industries and machines, humans can now process these natural gifts and store them for a longer period.
1. Explain the brief advantages of utilizing a bag containing minute pores?
The major benefits of using a bag containing minute pores are referred to as a Bagging technique.
In order to achieve desirable pollination, a bag with minute pores is used. Gas will enter the bag through the pores.
As a result, gaseous exchange will occur, allowing the flowers to breathe and photosynthesis.
The container, on the other hand, holds pollen grains out of touch with the herb, which is undesirable.
As a result, there is no fertilization and the plant is sprayed with pollen from a desirable plant. This process is referred to as the bagging technique.
2. Why is emasculation performed before anthesis? complete the following sentence: emasculation is the removal of anther, it is required in the process of……….
This necessitates an understanding of flower anatomy, pollination mechanisms, fertilization, and flowering physiology. The stamens are removed before anthesis to acquire a female parent, and pollen from the desired male parent is transferred to its stigma in the emasculation technique.
Emasculation is an artificial hybridization process in which female flowers' stamens are separated from bisexual flowers to avoid self-fertilization. Much before the anthers mature, this process takes place. The method of extracting anthers from bisexual flowers before they mature is known as emasculation. After that, the emasculated flower is bagged to avoid pollination. Emasculation is the method of separating the anthers from a bisexual flower before anthesis or bud opening. In order to allow selective hybridization, emasculation is needed to prevent self-pollination in a bisexual flower. After that, the emasculated flower is bagged to ensure that pollen from other sources does not fertilize the egg. Only female flowers are bagged in the case of unisexual flowers to allow selective hybridization.
3. What does pollination in plants mean?
Every flowering plant also known as angiosperms, have a stamen and ovary. During pollination in a flowering plant, the pollen grains from the stamen of a flower is transferred to the ovaries of the plant and this process is known as pollination and it is the basic process that happens in a plant to reproduce. The pollen grains are deposited on the hollow space of the flower i.e, pistil on its surface known as stigma. Here, the pollen germinates to give a pollen tube that travels down to the ovaries in the flower. In the case of double fertilization, endosperm and seed are formed. The agents of pollination vary from insects to wind. Pollination can also be done through artificial means but in primitive plants, pollination might have happened because of the insects and all the other agents are a recent development. The most important insect that might have contributed to the development of plants in the primitive stage is the “Beetle”. Even the bees and the butterflies are of a much later origin.
4. Is artificial hybridization possible in plants?
Artificial hybridization is a recent development in the pollination of flowering plants. Generally, pollen grains from the stamen part of the flower is carried by a pollinating agent like the insects to the ovaries of a plant. This process is known as pollination and we can not control what type of pollen grains reach the ovaries from the stamen. But, in the case of artificial hybridization, humans can control which pollen grains are to be moved to the ovaries for reproduction. Incompatibility between the stigma and ovaries of a flower is an issue in commercial farming as in this case, the plant can not actively reproduce. When the pollen grains are transferred to stigma, it accepts only the compatible pollen grains and rejects the incompatible ones. Artificial hybridization is possible in plants through bagging and emasculation techniques. Anthers from a bisexual flower are removed with the help of forceps and this is known as emasculation. The flower is masked with a cover to stop interacting with undesirable pollen grains and this process is called bagging. To know more about emasculation and bagging, refer to the above article.
5. Explain how is pollination important?
Pollination is a reproductive process in which the pollen grains from the stamen are transferred by a pollinating agent like bees, insects to the ovaries of a plant. This can happen in two ways, cross-pollination across two different plants and self-pollination within the same plant. Stigma, present on the ovary selects the suitable pollen grains for reproduction and rejects the incompatible pollen grains. It is very important for sexual reproduction in plants and to produce offspring. Even human beings get fruits and flowers from this process. The Horticulture industry which commercially grows fruits and flowers is extensively dependent on this process. Research into this topic also gave new techniques like artificial hybridization that have added huge economic importance.
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