Seed (agriculture)

See also: Seed

Definition

Seed comes, through Latin, of the Greek sperma = seed, germ. This term also gave the sperm term. By analogy between the man and the farmer on the one hand, the woman and the ground of the other, it took in agriculture the direction of Graine which one plants for a harvest. Just as the man was supposed “to sow” the woman so that it carries a child, the farmer sowed the ground so that it carries a harvest.

In Agriculture, the seeds are Graine S, or by extension of other bodies of reproduction (Bulbe S, Tubercule S…), selected to be sown S. It is the first Intrant of the culture.

Since first half of the twentieth century, the production and the marketing of the seeds are the object of a definition and an administrative control.

Production

Since the beginnings of agriculture (there is more than 10.000 years), the first farmers put aside seeds seedlings answering certain agronomic criteria as well as possible (sizes, facilitated to get rid of the envelope, resistance,…), or social (beauty, craving, identity). They did not consume seeds thus selected and replanted them the following countryside.

The migration of the farming populations, the colonization of new spaces, the parcelling out of the establishments, induced a selection differentiated from one area to another. The people farmers indeed acclimatized the species to the local environment. This acclimatization led to the appearance of local varieties which constitute the Biodiversité domesticates.

Today in the developed countries, the production of the seeds is mainly assured by Semencier S, indicating term of the specialized companies in the selection, the production and the marketing of selected seeds. To multiply the seeds in order to obtain a sufficient quantity from it to provide the market, these companies sign from the contracts with farmers whom one calls multipliers. Then the seeds are sorted, gauged, treated and conditioned in stations of seeds. After controls, they are marketed in the form of certified seeds (for the species of field crop). In France, and in other European countries, this selection is regulated (see chapter regulation).

Quand the farmers continue to select and to make evolve/move the traditional varieties of seeds, without calling upon the seeds selected by the seed-bearer companies, one speaks about country seeds. The restrictive character of decree 81-605 excludes this practice. This is why certain movements (enquiring, associations or movements of farmers ) call it into question (see chapter on the regulation for more details).

One speaks about farm Semence when a farmer resows a harvest resulting from certified seeds bought with seed-bearer. There is not creation of an original variety.

Methods of production

Sexuée multiplication

The sexuée multiplication is the first way of natural multiplication of the plants. The seed comes from fecundation by pollen of the ovule present in the flower of the plant. Two types of reproduction exist:
  • case of the plants which are autofécondent, species known as Autogame S (like corn or pea); it is said that there is autofecondation ()
  • case of the plants whose fecundation is cross, species known as Allogame S (like beet, corn or clover). In this last case, for the production of seeds of certain varieties resulting from crossings (hybrid varieties F1 in particular), it is necessary to take precautions particular of insulation in order to be assured that the “female” flower is fertilized by the pollen of the male flower selected.

Many species (as colza) has intermediate modes of reproduction, or known as mixed (rate of allofecondation ranging between 10 and 90%) and the species known as autogames have a rate of allofecondation in general not no one (0.5% The production of seeds of the species of which the usually collected part is not the seed (sheets and stems for the meadow plants, roots, sheets or stems of the pot species) requires techniques of particular productions (they are often bi-annual or perennial species).

Vegetative multiplication

The vegetative multiplication is a way of multiplication present in nature at many plants. It is in particular the case of the tubers (potato), of the bulbs (onions, tulips) or of let us stolons (strawberry plants). As of antiquity, the man extended it to other plants, in particular the vine and the fruit trees. More recently artificial techniques of vegetative multiplication were developed. One exploits the Totipotence cellular present at the plants in the bud apicalBourgeon Apical: Cluster of cell not differentiated located at the end from the plant by which the growth is carried out. Their animal equivalent are the cells embryonnaires to reproduce with identical the seedling which one selected. For the cultivated species, one speaks about Clones. This technique was developed for the plants Allogame S whose cross fecundation involved a genetic mixing which increased heterogeneity generations after générations.
Different technique from vegetative multiplication
  • Propagation by cutting or grafting
Primarily for the woody plants (trees, shrubs).

See also: Propagation by cutting

See also: Clerc's Office (botanical)

  • Vitro plan

In vitro culture is used today for the production of certain decorative plants, for the multiplication of certain palm trees, the first generations of potato seedlings. It consists with cloner of very many times the plants located like interesting agronomically.

  • artificial Seeds

This technique is not yet at the point today, in particular because of the problems of stabilization of the embryo. The project of the artificial seeds is to directly produce “seeds” and artificially starting from a cell of the plant to be multiplied (cloner). One thus avoids the stage of the multiplication to the field. One uses the cellular Totipotence by cultivating cells of an explant taken on the plant mother. One puts in vitro culture the cal obtained, to obtain a very great number of it. After a dispersion of the cells one starts embryogenesis with a set of vegetable hormones. Each cell will multiply but this time by giving an embryo. Remain to stabilize it and set up a nutritive coating and a suitable protection who MIME the Cotyledons and wraps it natural seeds.

Economy

In France the selection and the production of the seeds represent:
  • more than 70 companies of selection
  • more than 240 production companies
  • more than 20.000 multiplying farmers
  • more than 22.000 distributers (co-operatives, trades, agricultural, garden-centers,…)who sell to the farmers and with nearly fifteen million gardeners amateurs.
  • the first seed-bearer group of French origin is Vilmorin - Limagrain which controls inter alia the companies: Clause, Tézier, Advanta, LG-seeds, Verneuil… The Group is also an important actor of the North-American market, through the AgReliant company. He is located at the 2nd world rank in that of the seeds for the professionals. He has subsidiary companies in the majority of the European countries.
  • the six world leaders are Pioneer Hi-Bred International (2 164 M€ of turnover in the seeds, subsidiary of Dupont de Nemours), Monsanto (1 936 M€, the United States, subsidiary of Pharmacia Corporation), Syngenta AG (1 068 M€, Swiss independent company), Limagrain (1093 M€ (2006), co-operative Frenchwoman), Seminis Inc. (479 M€, American independent company) and Advanta (421 M€, subsidiary of Astra-Zeneca). The worldwide market of the marketed seeds is estimated at 30 billion US$.

Surfaces in multiplication of seeds and seedlings occupy nearly 330.000 ha for a total production of more than 1.300.000 tons.

Regulation

Origin

During the twentieth century, a regulation on the seeds was installation gradually in France and in the majority of the European countries.
  • the decree of December 5th, 1922 (J.O of December 8th, 1922, p. 11167) sets up the first version of the catalog of the crop plants. This catalog relates to only “obtaining a species or a new variety” and the conditions under which the depositor can assert “the exclusive use of the denomination given”.

  • the decree of March 26th, 1925 , (OJ of March 29th, 1925, p. 3189-3191) institutes a register of the selected plants, heading “Repression of the frauds in the trade of the corn seeds”. The concept of repression of the frauds devotes the seed implicitly the seed like a stable product and clearly identifiable.

  • the decree of November 16th, 1932 (repealed) (OJ of November 19th, 1932, p. 12006-12067) institutes” a catalog of the species and varieties of crop plants and a register of the selected plants of field crop”. This decree evokes for the first time the protection of obtainings. It notes:

“Art.12- the mention “species or variety” registered with the register of the selected plants is the exclusive property of the obtentor of the innovation. It will be able to make state of it only after the final inscription. The trade of the seeds, tubers, bulbs, grafts or cuttings of a registered plant is subordinated to the authorization express of the obtentor.”

  • on October 11th, 1941 is created GNIS (Interprofessional National Grouping of the Seeds) by the law n°14194, law supplemented by the law n° 383 of August 2nd, 1943.

  • 1961 , sees creation by the seed-bearer professionals of UPOV (Union for the Protection of Varietal Obtainings).

  • Decree 81-605 of May 18th, 1981 , (OJ Of May 20th, 1981) stipulates that: “The Minister for agriculture holds a catalog comprising the restrictive list of the varieties or varietal types whose seeds and seedlings can be “put on the market” on the national territory. The inscription on the catalog is subordinated to triple condition which the variety is distinct, stable and sufficiently homogeneous.” This decree “is taken for the application of the law of August 1st, 1905 on the frauds and falsifications as regards products and services, with regard to the trade of the seeds and the seedlings”.

Marketing

In Europe, to be marketed, the seeds of the majority of the cultivated species must be controlled and certified (for the species of field crops). In addition, for the great majority of the agricultural and pot species a variety of a seed must be registered either with the official Catalog of the species and varieties national, or with the Community catalog (which is the sum of the catalogs of the various countries of the European Union).

Discussion in progress

Certain aspects of this regulation are in the course of discussion at the European level in order to best adapt to the current concerns. The current legislation aims bringing guarantees to the user, facilitating the exchanges, framing the production of seeds, allowing a financing of research and at structuring the filière.

According to its detractors, this legislation involved an impoverishment of the genetic resources as well as impossibility for the farmers of carrying out their own selection (contrary to what is done in the breeding). Lastly, this regulation, would result in primarily selecting seeds adapted to the practices of industrial agriculture, for example by taking of account the aptitude for the plants to assimilate Ammonitrate (nitrate fertilizer: mix ammonia and nitrates). In causes the criteria selected are of homogeneity, stability as well as the agronomic performances necessary for the recording of the new varieties. These technical specifications would not correspond to the needs for a less intensive agriculture, the organic farming for example.

Intellectual property

In the United States, the plant varieties can be patented. In Europe, the certificate of vegetable obtaining (COV) was designed to apply to a living matter. This system aims at protecting work from the obtentor (undertaken seed-bearer who produced the variety) while maintaining the free access to the genetic resource for the other seed-bearer companies.

Quality standards of the seeds

The regulation fixed four quality standards: analytical purity, varietal purity, germinative faculty and the medical condition.

Analytical purity

It is a question of measuring in the batches the presence of seeds of plants of other species in general adventitious (specific = of the species)
  1. Prélèvement of representative samples of the whole of the batch of seed.
  2. Enumeration and identification of seeds of foreign species (other species cultivated, bad grasses…). This stage is difficult to carry out if the seeds resemble each other, for example between colza and mustard.
  3. the results are expressed as a percentage weight of the pure seeds in the species indicated of a batch concerned. They are compared with the official standards. For example, one should not in the case of find more than 10 foreign seeds to the 500g cereals with straw.
  4. Refusal or acceptance of the batches for the certification of the seed. For example, the corn of prébase and base must have 99% of purity and the corn certified 98%. Starting material G 0 - > Seed of prébase G1 G2 G3 - > basic Seed G 4 - > certified Seed R 1 - > Farmer

Varietal purity

It is a question of measuring within the batch of seeds the seed rate deviating from the model plant of the variety. It cannot be realized by observing the seeds directly at least whenever there are no differences phenotypical (of aspect) between seeds. One can measure it by observing the results of a Semis at the end of one year, while looking in the field with the épiaison (moment or ears is formed) or with flowering, by observing at the same time the port of the plant and his ear or his inflorescence or by carrying out the electrophoresis of the Gliadine S (proteins of reserve of seed) for a plant like corn.

Germinative faculty

It is the number of viable germs obtained within N days (different according to the species) and under conditions of optimal temperature and hygroscopy. A germ is regarded as viable if the seed germinated and that its Phénotype corresponds to a certain standard. For the forest seeds, the test with tétrazolium makes it possible to know if the seed is alive without having to wait until it germinates.

The medical condition

The seeds must be unscathed diseases.

Notes and references of the article

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