Vegetative reproduction is based on the ability of plants to regenerate (restoration of lost organs). In most lower plants the body, dissected into i

Vegetative propagation in plants (by rhizomes, runners, bulbs, buds; viviparity) [reproduction, structures, types, methods]

Vegetative reproduction is based on the ability of plants to regenerate (restoration of lost organs). In most lower plants the body, dissected into individual cells, regenerate by each of them. In flowering plants, vegetative propagation is carried out by formation of buds in some organs, most commonly on stems, roots, rarely on the leaves, but it also can be carried out by the body fragments, pieces of the shoots. For example, jointed stems of the cactus may break into pieces, each of which will give rise to the new individual.

Besides natural vegetative propagation, there are also some methods of artificial, mostly by cuttings and layering (see: Plant reproduction by cuttings and layering).

Reproduction by rhizomes

In the axils of scale-like leaves on rhizomes originate buds that develop into vertical aerial shoots. Adventitious roots form in the lower nodes of the latter. After rhizomes have been rotted or after its artificial dismemberment into sections each of them gives rise to a new individual.

For example perennial grasses propagate such way, and sometimes form a huge mass of rudiments, such as difficultly eradicable wheat grass (Agropyrum repens). Due to the annual rise of rhizomes, the plant can move far away from their place of primary origin. The length of the annual increase in the Sakhalin buckwheat, for example, equals to 150-300 cm, in the horsetail — up to 10-15 cm, in the willow-herb — up to 85-100 cm, and so on.

Reproduction by runners, stolons

Reproduction by runners or stolons is similar to propagation by rhizomes. Shoots in this case, are above-grounded, prostrate on the ground, for example in strawberry, bramble and others.

The length of the annual growth of runners, for example at the saxifrage, equals to 4 cm, and in strawberry — 1.5 m.

Diagram 128. Vegetative reproduction of pink sow-thistle (Cirsium arvense): 1 and 1a — seedlings; 2 — plants by the end of the first year of vegetation; 3 — adult flowering plant; 4 — the offspring on the underground part

Reproduction by bulbs

In the axils of scale-like leaves of bulb originate new buds that in the further development give rise to new plants. Ornamental plants propagate such way — tulips, lilies, daffodils and other. Bulbs sometimes form in the inflorescences (some onions, garlic). In this case, usually forms a small amount of flowers.

Viviparity in plants

In the axils of bracts of some plants produce small leafy shoots, falling to the ground and germinating into new individuals. These plants are often called viviparous. Examples of these can serve a steppe bluegrass (Poa bulbosa var. Vivipara), viviparous buckwheat (Polygonum viviparum). Such viviparous plants are found mainly in areas where the plants do not have time to go through the development cycle due to a short growing season (in the steppes, in the tundra, in high alpine regions). Taken from http://worldofschool.org

Reproduction by adventitious buds

Plant propagation sometimes carries out through the formation of adventitious buds on the roots. For example in pink sow-thistle (Cirsium arvense), pernicious weed, develops strong root system that penetrates the ground to a depth of 9-10 m. From the vertical roots extend shorter horizontal roots, curving downward at their ends. In place of the bending occurs adventitious bud, forming a vertically growing shoot, which comes to the surface (diagram 128). During tillage with plow sow-thistle roots break into parts, each of which forms a new individual. Consequently, the fight against thistles is very difficult. The same way also propagates yellow sow thistle (Sonchus arvensis) and others. The one too soiled field by sow-thistle had on 1 hectare of arable land had over 5.25 million cuttings of pink sow-thistle roots and 16.6 million rudiments of yellow sow-thistle. For comparison, 1 hectare seeds with 3 to 4 million of wheat grains.

In some wild plants, such as the cuckooflower (Cardamine pratensis), in the notches of leaves appear adventitious buds that root, and after rotting of sheet on the ground, you can find a few new cuckooflower plants arisen by a vegetative method. Formation of buds on the leaf observes in a small quantity of plants. Some ornamental plants such as begonias propagate by parts of the leaves.