The reproduction in plants like any other organism aims to bring forth new offspring. Plants are capable of attaining both the kinds of reproductive processes, that is, sexual reproduction and asexual reproduction. Sexual reproduction occurs through the fusion of gametes. Asexual reproduction is carried out through various processes like budding and vegetative propagation.
Reproduction in plants is referred to as the event of the production of new offspring from the plants. The course of reproduction can be either sexual or asexual. Sexual reproduction is done by the formation of a new offspring that happens due to the fusion of the gametes, that is, pollen and the ova. Asexual reproduction is a course of birth of the offspring in absence of the fusion of gametes.
In the case of asexual reproduction, the offspring produced are genetically identical. Characteristically, the new organisms developed from asexual reproduction are enclosed in protective seeds that can live long and the offspring are dispersed at a distance from the plant. In flowering plants, the seeds are found inside the fruit that protects the seeds and enables their dispersal.
Reproduction in plants are found to be of two different types. That is sexual reproduction and asexual reproduction.
Figure 1: Reproduction in Plants
The sexual reproduction of plants is associated with the gametes fusion process that gives birth to new offspring. It is considered to be a superior method of reproduction since it brings forth new variations and the evolution of the offspring. In the stage of flowering, multiple events occur in different parts of plants that lead to the birth of a new plant. It is in this stage that the plants reproduce sexually and meiosis occurs which is a critical phase in the reproduction of plants. After fertilization, seeds and fruits are formed. The resultant product of this event is the fruits and the seeds. The seeds eventually grow into new plants.
This process does not require the involvement of other external factors that are needed during the production of flowers. For example, it is not needed to attract pollinators and there is no necessity to disperse the seeds. Plants are known to undergo many kinds of asexual reproduction mainly, apomixes and vegetative reproduction. Apomixes is the process by which plants can make seeds without fertilization. Vegetative production results in new plans without the production of seeds or spores.
Different modes of vegetative propagation and their distinct features are mentioned below −
Figure 2: Asexual reproduction
In some plants, the vegetative parts like leaves, stems, and roots are capable of giving rise to new plants. In the natural process, the roots of some plants can be modified into tubers. In the tubers, roots can form adventitious buds and can grow into new plants. The nodes of stems that bear buds are capable of growing new plants.
Take the case of budding in yeast. In this process, a bud is developed and the nucleus move the buds, and the bud detaches from the parent cells and forms new yeast cell.
Some of the plants can disperse into fragments and they can grow into new individuals.
Plants produce through spores and germinate under certain conditions. For example, fungi.
Some of the layers of a plant are mentioned below −
Figure 3: Parts of flower
Calyx: These are made of sepals. Some of the plants have green sepals while some are known to have colourful sepals. The purposes of sepals are to protect flowers.
Corolla: It is the group of petals, the colour of the petals helps attract birds and insects aiding in the course of pollination.
Androecium: It contains stamen which is the male reproductive part made of filaments and anthers.
Gynoecium: It is made of carpels. Pistils have stigma, ovaries, and styles. Ovules are present in the ovary. The ovaries are the site where seeds of plants are produced.
The differences between sexual and asexual reproduction are discussed below
Asexual Reproduction | Sexual reproduction |
---|---|
It requires only a single parent. | It requires the involvement of a male and a female. |
Gametes do not fuse. | Gamete fusion occurs. |
The mitotic division takes place only. | Meiosis is noticed in certain stages. |
The new plants born are genetically identical. | The new plants reflect variations in genetics. |
Table 1: Difference between asexual and sexual reproduction in plants
Plants are capable of producing through both sexual and asexual processes. The sexual mode of reproduction involves flowers and the courses of pollination. Then there is asexual reproduction, this method of reproduction produces plants that are thoroughly identical to the plant, as the mixing of male and female gametes does not take place. These plants are known to survive under environmental conditions that provide stability.
Q1. What are some important features of sexual reproduction?
Ans. In this case of reproduction, two parents are present. Gametes are formed in this reproduction and they are fertilized. This course of reproduction is lengthy and slower compared to asexual reproduction. Genetic and physical attributes are different from the offspring of the parent plant.
Q2. What are the advantages of asexual reproduction?
Ans. In a short period, a large number of plants can be produced. Pollination and seed dispersal is not required. Certain variants of plants grow the best with this vegetative propagation. The new plants are identical to the parent.
Q3. What are the post-fertilization changes in plants?
Ans. The zygotes progress into an embryo. The ovary is developed into fruit and seeds are formed inside fruits. The sepals and petals fall off after fertilization. The seed retains the embryo within it. These seeds are further dispersed by wind, water, and other creatures and they germinate further under favourable conditions giving birth to new plants.