propagation

propagation
propagational, adj.
/prop'euh gay"sheuhn/, n.
1. the act of propagating.
2. the fact of being propagated.
3. multiplication by natural reproduction.
4. transmission or dissemination.
[1400-50; late ME propagacyon < L propagation- (s. of propagatio). See PROPAGATE, -ION]
Syn. 4. spreading, dispersion, diffusion.

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▪ of plants
Introduction

      in horticulture, the reproduction of plants by any number of natural or artificial means.

Sexual propagation.
      With crops that produce seed (seed and fruit) freely and come true closely enough for the purposes in view, growing from seed usually is the cheapest and most satisfactory method of plant propagation. Many types of seeds may be sown in open ground and, barring extreme wetness or extreme aridity, germinate well enough for practical purposes. Other kinds, however, are so exacting in their requirements that these are best met in a propagating house where humidity and temperature can be more rigidly controlled. Because of their high oxygen requirement, the medium in which the seeds are sown generally should contain more sand (or other filler or mulch material) than ordinary garden soil does. Greater porosity makes these media more subject to rapid drying, however, and moisture must be carefully monitored. Because many soils harbour fungi destructive to sprouting seed and young seedlings, soil that is used for germinating seed commonly is sterilized by heat or chemicals. Many diseases of plants are caused by fungi and bacteria carried in or on the seed itself, and treatment of the seed with disinfectants is beneficial.

Asexual propagation.
      Some species of plants, in their cultivated forms, do not produce seed—e.g., banana, pineapple, and sugarcane. In a great number of cultivated species, seedlings vary so much that the desired traits are found in only a small proportion. For these and other reasons, horticulturists resort to asexual propagation—i.e., the division or separation and indefinite subdivision of the original plant having the desired traits.

      Many people have held the opinion that asexual propagation is unnatural and that plants thus derived lack the hardiness or the sturdiness of plants grown from seed. Asexual propagation, however, is not unnatural; some of its forms—e.g., layering and grafting—are rather common in nature. The only justification for the generalization that asexually propagated plants lack hardiness or sturdiness is the fact that virus diseases can be transmitted by asexual propagation and that most such diseases cannot be transmitted through seed.

      Methods of asexual propagation include bulb division, layering, cutting, and grafting. Bulbs and other underground rootlike structures, such as tubers and corms, may be divided as they mature. The sections are then placed in a moist medium to root. In layering, the stem of a large plant is notched and wrapped in moist sphagnum moss or bent to the ground and covered with moist soil; when roots appear, growing out of the moss, the stem is cut below the roots and potted. Auxins (auxin) (growth hormones) are often added to the wounds or soil to stimulate rooting. Stem cuttings are rooted in water or a moist potting medium such as sand, peat moss, or vermiculite. When cutting or layering are not feasible, a bud or twig of one plant is grafted (graft) onto the fully developed root system of another.

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Universalium. 2010.

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  • propagation — [ prɔpagasjɔ̃ ] n. f. • h. XIIIe « descendant »; lat. propagatio, de propagare 1 ♦ (1380) Multiplication par voie de génération. La propagation de l espèce. ⇒ reproduction. « l Église, qui ne voit dans le mariage que la propagation de l humanité… …   Encyclopédie Universelle

  • Propagation — can refer to:*Reproduction, and other forms of multiplication or increase **Plant propagation, the production of more plants by seeds, cuttings, grafting or other methods **Propagation of schema, in artificial reproduction *Wave propagation, the… …   Wikipedia

  • Propagation — Prop a*ga tion, n. [L. propagatio: cf. F. propagation.] [1913 Webster] 1. The act of propagating; continuance or multiplication of the kind by generation or successive production; as, the propagation of animals or plants. [1913 Webster] There is… …   The Collaborative International Dictionary of English

  • propagation — PROPAGATION. s. f. Multiplication par voye de generation. La propagation du genre humain. la propagation de l espece. On dit figur. La propagation de la foy; pour dire, l Extension, l accroissement, l augmentation de la foy dans les pays… …   Dictionnaire de l'Académie française

  • propagation — mid 15c., from O.Fr. propagacion (13c.), from L. propagationem (nom. propagatio) a propagation, extension, noun of action from propagare multiply plants by layers, breed, from propago (gen. propaginis) that which propagates, offspring, from pro… …   Etymology dictionary

  • Propagation — oder Propagierung (lat. propagare ‚ausdehnen‘) steht für: das Kundtun einer Meinung, siehe Propaganda in technisch wissenschaftlichem Zusammenhang die Ausbreitung von Information(en), Signalen, Energie, Wirkung, usw., siehe Ausbreitung (Physik)… …   Deutsch Wikipedia

  • propagation — propagation. См. размножение. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Propagation — (v. lat.), Fortpflanzung …   Pierer's Universal-Lexikon

  • Propagation — (lat.), Ausbreitung, Fortpflanzung; propagieren, verbreiten …   Meyers Großes Konversations-Lexikon

  • Propagation — Propagatiōn (lat.), Fortpflanzung, Verbreitung; propagieren, fortpflanzen, verbreiten …   Kleines Konversations-Lexikon

  • propagation — index maternity, publication (disclosure), publicity, report (detailed account), transmittal Burton s Legal Thesaurus …   Law dictionary

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