Asexual Reproduction: Vegetative Propagation
In nature, plants propagate themselves in two ways – sexually (by seed) and vegetatively (using a part of the original plant, such as an offset or plantlet). Vegetative propagation is a form of asexual reproduction of a plant. Only one plant is involved and the offspring is the result of one parent. The new plant is genetically identical to the parent. the ability of plants to reproduce without sexual reproduction, by producing new plants from existing vegetative structures. A form of asexual reproduction in plants, in which multicellular structures become detached from the parent plant and develop into new individuals that are genetically identical to the parent plant. For example, liverworts and mosses form small clumps of tissue (called gemmae) that are dispersed by splashing raindrops to form new plants.
There are many techniques used for vegetative propagation:
This method of plant or tree grafting is used for inserting a piece of stem with buds (scion) into the stock. It is the transfer of a part of one plant to the stump of another plant. The part taken from a plant is a portion of the stem with many buds. This portion is called scion and is selected for the quality of its fruit. The stump to which the scion is attached is called the stock. Stock is selected for qualities such as disease resistance and hardiness.
Layering is the method of inducing certain branches of the parent plant to produce roots by bending and pegging them to the ground around the parent plant leaving the tips exposed. Once the roots develop the branch is then cut off from the parent body.
Propagating plants from cuttings method is also called striking or cloning, in which a piece of plant containing at least one stem cell is placed on suitable medium like soil, potting mix or rock wool. This cutting helps to produce new roots, stems or both, and develops into a new plant.
Stolons or runners are the stems which grow underground to form new plants at the end of the nodes. These are stems that grow just under the ground; these runners have the capacity of producing new clones of the same plant from the buds at the tips. The stolons can be cut, and then planted as separate individual plants.
Vegetative propagation is one of the ways to reproduce asexually. Plants raised by vegetative propagation can bear fruits and flowers earlier than those produced from seeds. The offsprings are genetically identical and therefore advantageous traits can be preserved. They can raise crops like bananas, sugarcane, potato, etc that do not produce viable seeds. The seedless varieties of fruits are also a result of vegetative propagation. The plants gradually lose their vigour as there is no genetic variation. They are more prone to diseases that are specific to the species. This can result in the destruction of an entire crop.