Plant propagation is the process by which new plants grow from a variety of sources:
seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...
s,
cuttings, and other plant parts. Plant propagation can also refer to the man-made or natural dispersal of seeds.
Propagation typically occurs as a step in the overall cycle of plant growth. For seeds, it happens after ripening and dispersal; for vegetative parts, it happens after detachment or pruning; for asexually-reproducing plants, such as strawberry, it happens as the new plant develops from existing parts. Plant propagation can be divided into four basic types: sexual, asexual (vegetative), layering, and grafting.
Countless plants are propagated each day in horticulture and agriculture. The materials commonly used for plant propagation are seeds and cuttings.
Sexual propagation
Seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...
s and
spore
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...
s can be used for reproduction (e.g.
sowing
Sowing is the process of planting seeds. An area or object that has had seeds planted in it will be described as a sowed or sown area.
Plants which are usually sown
Among the major field crops, oats, wheat, and rye are sown, grasses and leg ...
). Seeds are typically produced from
sexual
Sex is the biological distinction of an organism between male and female.
Sex or SEX may also refer to:
Biology and behaviour
*Animal sexual behaviour
**Copulation (zoology)
**Human sexual activity
**Non-penetrative sex, or sexual outercourse
** ...
reproduction within a species because
genetic recombination
Genetic recombination (also known as genetic reshuffling) is the exchange of genetic material between different organisms which leads to production of offspring with combinations of traits that differ from those found in either parent. In eukaryo ...
has occurred. A plant grown from seeds may have different characteristics from its parents. Some species produce seeds that require special conditions to
germinate, such as
cold treatment. The seeds of many
Australian plants
The Australian Native Plants Society (Australia) (ANPSA) is a federation of seven state-based member organisations for people interested in Australia's native flora, both in aspects of conservation and in cultivation.
A national conference is h ...
and plants from southern
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
and the
American
American(s) may refer to:
* American, something of, from, or related to the United States of America, commonly known as the "United States" or "America"
** Americans, citizens and nationals of the United States of America
** American ancestry, pe ...
west require smoke or fire to germinate. Some plant species, including many
trees, do not produce seeds until they reach maturity, which may take many years. Seeds can be difficult to acquire and some plants do not produce seed at all. Some plants (like certain plants modified using
genetic use restriction technology
Genetic use restriction technology (GURT), also known as terminator technology or suicide seeds, is the name given to proposed methods for restricting the use of genetically modified crops by activating (or deactivating) some genes only in respo ...
) may produce seed, but not a fertile seed. In certain cases, this is done to prevent the accidental spreading of these plants, for example by birds and other animals.
Asexual propagation
Plants have a number of mechanisms for asexual or
vegetative reproduction. Some of these have been taken advantage of by
horticulturists
Horticulture is the branch of agriculture that deals with the art, science, technology, and business of plant cultivation. It includes the cultivation of fruits, vegetables, nuts, seeds, herbs, sprouts, mushrooms, algae, flowers, seaweeds and no ...
and to multiply or
clone
Clone or Clones or Cloning or Cloned or The Clone may refer to:
Places
* Clones, County Fermanagh
* Clones, County Monaghan, a town in Ireland
Biology
* Clone (B-cell), a lymphocyte clone, the massive presence of which may indicate a pathologi ...
plants rapidly. Humans may utilize these processes as propagation methods, such as
tissue culture and
grafting
Grafting or graftage is a horticultural technique whereby tissues of plants are joined so as to continue their growth together. The upper part of the combined plant is called the scion () while the lower part is called the rootstock. The succ ...
.
Plants are produced using material from a single parent and as such, there is no exchange of genetic material, therefore vegetative propagation methods almost always produce plants that are identical to the parent. Vegetative reproduction uses plant parts such as roots, stems, and leaves.
In some plants, seeds can be produced without fertilization and the seeds contain only the genetic material of the parent plant. Therefore, propagation via asexual seeds or
apomixis
In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cuttin ...
is asexual reproduction but not
vegetative propagation.
Techniques for vegetative propagation include:
*Air or ground
layering
*
Division
*
Grafting
Grafting or graftage is a horticultural technique whereby tissues of plants are joined so as to continue their growth together. The upper part of the combined plant is called the scion () while the lower part is called the rootstock. The succ ...
and
bud grafting, widely used in
fruit tree propagation
*
Micropropagation
*
Stolon
In biology, stolons (from Latin '' stolō'', genitive ''stolōnis'' – "branch"), also known as runners, are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external s ...
s or runners
*
Storage organ
A storage organ is a part of a plant specifically modified for storage of energy
(generally in the form of carbohydrates) or water. Storage organs often grow underground, where they are better protected from attack by herbivores. Plants that have ...
s such as
bulb
In botany, a bulb is structurally a short stem with fleshy leaves or leaf basesBell, A.D. 1997. ''Plant form: an illustrated guide to flowering plant morphology''. Oxford University Press, Oxford, U.K. that function as food storage organs duri ...
s,
corms,
tubers, and
rhizome
In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...
s
*
Striking
Strike may refer to:
People
*Strike (surname)
Physical confrontation or removal
*Strike (attack), attack with an inanimate object or a part of the human body intended to cause harm
*Airstrike, military strike by air forces on either a suspected ...
or cuttings
*
Twin-scaling Twin-scaling is a method of propagating plant bulbs that have a basal plate, such as:
* ''Hippeastrum'', '' Narcissus'', ''Galanthus'' and other members of the ''Amaryllidaceae'';
* some members of the lily family ''Liliaceae'';
* ''Lachenalia'', ' ...
*
Offsets
Heated propagator
A heated propagator is a
horticultural device to maintain a warm and damp environment for
seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...
s and
cuttings to grow in.
This can be in the form of a clear enclosed bin sitting over a hot pad, or even a portable heater pointed at the bin. The key is to keep the moisture in the clear bin, while keeping lighting over the top of it, usually.
Seed propagation mat
An
electric seed-propagation mat is a heated
rubber mat covered by a metal cage that is used in
gardening
Gardening is the practice of growing and cultivating plants as part of horticulture. In gardens, ornamental plants are often grown for their flowers, foliage, or overall appearance; useful plants, such as root vegetables, leaf vegetables, fruits ...
. The mats are made so that planters containing
seedlings can be placed on top of the metal cage without the risk of starting a
fire. In extreme cold, gardeners place a loose plastic cover over the planters/mats which creates a sort of miniature
greenhouse
A greenhouse (also called a glasshouse, or, if with sufficient heating, a hothouse) is a structure with walls and roof made chiefly of Transparent ceramics, transparent material, such as glass, in which plants requiring regulated climatic condit ...
. The constant and predictable heat allows people to garden in the winter months when the weather is generally too cold for
seedlings to survive naturally. When combined with a lighting system, many plants can be grown indoors using these mats.
See also
*
Adventitious
*
Clonal colony
A clonal colony or genet is a group of genetically identical individuals, such as plants, fungi, or bacteria, that have grown in a given location, all originating vegetatively, not sexually, from a single ancestor. In plants, an individual in s ...
*
Fruit tree propagation
*
Orthodox seed
Orthodox seeds are seeds which will survive drying and/or freezing during ex-situ conservation, as opposed to recalcitrant seeds, which will not. According to information from the U.S. Department of Agriculture, there is variation in the ability of ...
*
Recalcitrant seed
*
*
Propagation of grapevines
The propagation of grapevines is an important consideration in commercial viticulture and winemaking. Grapevines, most of which belong to the ''Vitis vinifera'' family, produce one crop of fruit each growing season (vine), growing season with a lim ...
*
Weeping willow (tree) is an ornamental tree (''Salix babylonica'' and related hybrids
*
Propagation of Christmas trees
The Propagation of Christmas trees is the series of procedures carried out to grow new Christmas trees.
Many different species of evergreen trees are used for Christmas trees. The most common of these species are classified in the four genera: ...
*
Hemerochory
*
Escaped plant
References
External links
Reference Guide to plant care handling and merchandising
Bibliography
Charles W. Heuser. The Complete Book of Plant Propagation, Taunton Press, 1997.
{{DEFAULTSORT:Plant Propagation
Propagation
Horticultural techniques
Agronomy
Forest management