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Vegetative propagation
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- It is a type of asexual reproduction in which new plants are produced from roots, stems, leaves and buds.
- As plant reproduction is through the vegetative parts of the plant, it is known as vegetative propagation.
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Process
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- Flower buds develop into flowers. Apart from flower buds, there are buds in the axil (point of attachment of the leaf at the node) of leaves which develop into shoots.
- These buds are called vegetative buds.
- A bud consists of a short stem around which immature overlapping leaves are present. Vegetative buds can also give rise to new plants.
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Bryophyllum (sprout leaf plant)
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- Bryophyllum (sprout leaf plant) has buds in the margins of leaves.
- If a leaf of this plant falls on a moist soil, each bud can give rise to a new plant.
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Roots
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- Roots of some plants can also give rise to new plants.
- Example: Sweet potato and dahlia.
- Plants such as cacti produce new plants when their parts get detached from the main plant body.
- Each detached part can grow into a new plant.
Leaf of Bryophyllum with buds in the margin
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Grafting
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- Vegetative propagation is used in methods such as layering or grafting to grow many plants like sugarcane, roses, or grapes for agricultural purposes.
- Plants raised by vegetative propagation can bear flowers and fruits earlier than those produced from seeds.
- Such methods also make possible the propagation of plants such as banana, orange, rose and jasmine that have lost the capacity to produce seeds.
- Another advantage of vegetative propagation is that all plants produced are genetically similar enough to the parent plant to have all its characteristics.
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Budding
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- A new organism develops as an outgrowth from the body of the parent organism.
- Example: Yeast is a single-celled organism and can only be observed under a microscope.
- It is observed that the small bulb-like projection coming out from the yeast cell is called a bud.
- The bud gradually grows and gets detached from the parent cell and forms a new yeast cell.
- The new yeast cell grows, matures and produces more yeast cells.
- Sometimes, another bud arises from the bud forming a chain of buds.
- If this process continues, a large number of yeast cells are produced in a short time.
Reproduction in yeast by budding
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Fragmentation
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- In multicellular organisms with relatively simple body organization, simple reproductive methods can work.
- Example: Spirogyra simply breaks up into smaller pieces upon maturation.
- These pieces or fragments grow into new individuals.
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Spore Formation
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- Spores are asexual reproductive bodies.
- Each spore is covered by a hard protective coat to withstand unfavorable conditions such as high temperature and low humidity.
- Under favorable conditions, a spore germinates and develops into a new individual. Plants such as moss and ferns reproduce by means of spores.
- Example: In bread mold (Rhizopus), the thread-like structures are not reproductive parts.
- The tiny blob-on-a-stick structures are involved in plant reproduction.
- The blobs are sporangia, which contain cells, or spores, that can eventually develop into new Rhizopus individuals.
- The spores are covered by thick walls that protect them until they come into contact with another moist surface and can begin to grow.
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