The mode of reproduction that does not involve the fusion of male and female gametes and produces individuals that are genetically identical to the parent is known as Asexual reproduction. In this article, you will go through the asexual reproduction in plants, its types, methods, and so on. So, let us start by knowing more about asexual reproduction in the coming section.
Asexual Reproduction in Plants Definition
Asexual reproduction refers to the formation of a new organism from a single parent with no involvement of gametes or sex cells. Asexual reproduction is used by many unicellular and multicellular organisms. Budding, fragmentation, vegetative propagation, and spore formation take place in the process of Asexual Reproduction in plants. No flowers are required for this method. The plants produced by asexual reproduction tend to thrive well in stable environments.
Types of Asexual Reproduction in Plants
Asexual reproduction in plants takes place two ways, as mentioned below –
Natural Methods
Natural methods of asexual reproduction include self-propagation. Below mentioned are the various ways in which a plant self propagates.
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From the buds present on the surface of the stem, plants such as ginger, onion, dahlia, potato, grow. Under favorable conditions, these buds sprout producing leafy shoots.
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In sweet potatoes, new plants can grow from the adventitious buds or stolons.
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In Bryophyllum, the small buds grow on the margin of the leaves and get detached and grow into an independent plant.
Budding
Budding is the mode of asexual reproduction, wherein a new plant is developed from an outgrowth that is known as the bud. Due to the procedure of cell division at one particular site, a bud is formed.
For example, if you keep a potato for a long time, you can notice several small outgrowths, which are commonly referred to as ‘eyes’. Each of them can be planted to grow like a clone of an original potato plant.
Vegetative Propagation
It is a kind of asexual reproduction that usually occurs in plants, in which new plants are produced from the vegetative parts of the plants, i.e. roots, stems, or buds. Plants that are produced by vegetative propagation take less time to bear flowers & fruits as compared to those produced from seeds. Vegetative propagation in plants can occur both naturally or also can be artificially induced by horticulturists. Examples of vegetative propagation are Bryophyllum, onion, money plant, banana, etc.
The most common techniques of vegetative propagation are as follows.
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Stems – These are the stems that usually grow in a horizontal position that is above the ground. They have the nodes where the buds are formed. These buds usually grow into a new plant.
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Roots – When a new plant is developed from modified roots that are called Tubers. Example: Sweet Potato
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Leaves – In some plants, detached leaves from the parent plant can be used to grow a new plant. They promote the growth of small plants, called plantlets, on the edge of their leaves. Example: Bryophyllum.
Fragmentation
It is a kind of asexual reproduction of plants in which a new plant takes birth from a portion of the parent plant. This type of reproduction happens naturally where a small part of the plant falls off onto soil and then begins to grow up into a new plant. This method is generally used by nurseries and greenhouses to produce plants faster.
For example, you may have seen slimy green spots in ponds and other stagnant water bodies. They are known as algae. When water and nutrients are available, the process of fragmentation enables algae to expand and multiply rapidly. The algae divide into two or more fragments. Each fragment grows into new individuals.
Spore Formation
Spores in the life cycle are formed by many plants and algae. It is an asexual reproductive body that is being surrounded by a hard protective cover to handle unfavourable conditions such as high temperature and low humidity. As a result, they will live for a long period. Under favorable conditions, the spores germinate well and tend to grow into new plants. In this mode of reproduction, plants like moss and ferns are used.
Artificial Methods
An artificial method is when many plants are grown from a single plant using man-made processes. Below-mentioned is the artificial methods of asexual reproduction in plants:
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Cutting
Stem cuttings are used to reproduce plants like coleus and money plant, in which a part of the stem containing nodes and internodes is placed in damp soil and allowed to root. A new plant is grown by cutting a small portion of an existing plant, which is a stem or a leaf with a bud. This section is then planted in soil and watered. A new plant can be seen sprouting after a few days.
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Grafting
Grafting is a technique in which the parts of two separate plants are connected together so that they develop as a single plant. During grafting, the stems of two separate plants are cut and joined together in such a way that they grow as a single plant. One of the two cut stems has roots and is referred to as stock. The other stem, known as the scion, is cut without roots. Scion and stock cut surfaces are fitted and stitched together with a piece of cloth before being covered with a polythene cover. It guards the stem against infections and other issues. Soon after, the stock and scion combine to form a new plant. Characteristics of both the plants are present in the fruits of this new plant.
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Layering
It can be defined as a process in which a stem is attached to a plant and is lowered in the ground that is covered with the soil. The branches of the parent plant are allowed to go within the soil in a way that a portion of the branch emerges from the soil after layering. The part of the branch that is in contact with the soil develops roots and is detached from the parent plant. A new plant emerges from the buried branch in this way.
Micropropagation
When a large number of plants from an ex-plant is produced under laboratory conditions within a short period, that is known as Micropropagation. This helps and promotes the growth of rare and e
ndangered plant species that are difficult to grow under natural conditions.
Advantages of Artificial Method
Here are a few advantages of the artificial method:
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The new plant will have the same characteristics as the original plant.
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Fruit trees that have been grafted bear fruit considerably sooner.
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Plants require less care in their early stages.
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A single parent can produce many plants.
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Plants without seeds are available.
Key Points to Remember
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Individuals that are produced by asexual reproduction are genetically identical to the parent plant.
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Roots such as bulbs, tubers, rhizomes and stolons reproduce vegetatively.
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Some plants may produce seeds without fertilization by apomixis, in which the ovule or ovary produces new seeds.
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The advantages of asexual reproduction include increased maturity and more robust adult plants.
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Asexual reproduction can be carried out by natural or artificial means.