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WIEWS - Le Système mondial d'information et d'alerte rapide sur les ressources phytogénétiques pour l'alimentation et l'agriculture

Glossaire

Accession: Un échantillon de semences distinct, identifiable de façon unique représentant un cultivar, une lignée ou une population, qui est maintenu en stockage pour la conservation et l’utilisation.

Agroecological zone: A geographical area with similar characteristics in terms of climate, landform and soils, and/or land cover, and having a specific range of potentials and constraints for land use.

Collection de référence: Sousensemble sélectionné pour contenir le maximum de variation disponible dans un minimum d’entrées.

Collection sub-sets: In the context of Priority Activity 8 of the Second Global Plan of Action, Expanding the characterization, evaluation and further development of specific collection sub-sets to facilitate use, sub-sets refer to any grouping of accessions with respect to similarities expressed as morphological, agronomical, biochemical or molecular traits. Such grouping can help in selecting specific accessions for certain needs such as those governed by e.g. abiotic or biotic stresses.

Farming community: Refers to an indefinite number of individuals whose main livelihood is farming. They cultivate similar crops and apply similar technology(ies), and may form a defined rural unit such as a village, or comprise villages of different sizes.

Fixed line: Denotes a plant genotype that is characterized by homozygosity in most loci, ideally a so-called double haploid.

Genetic enhancement or Pre-breeding: The concepts refer to activities aimed at transferring genes, gene combinations and/or genetic variability from unadapted sources into more usable breeding materials that can be used as parents in breeding programmes. Two distinct approaches can be identified: (A) Introgression of the desired genetic traits into the elite gene pool of adapted material. This is the most common approach to genetic enhancement and used, for example, in transferring major gene disease resistances. Introgression can be achieved by repeated crosses (backcrossing) or by using biotechnological techniques. (B) Incorporation, or base-broadening, which is the large-scale development of locally adapted populations from unimproved germplasm stocks, through a long-term, population oriented approach. It is a less commonly used approach to genetic enhancement.

Genetic heterogeneity: In the context of indicator 35, it refers to the genetic variability at the level of both the crop and the cropping system, or agro-ecosystem.

High risk area: A geographical area characterized by abiotic and biotic stress factors - including those caused by human intervention - to the extent that crops or plant populations run the risk of being genetically impoverished, numerically diminished, or even lost.

Historical varieties: Varieties or cultivars, including locally adapted cultivars, which were once registered on formal (official) variety lists but have since been de-listed and made redundant. The epithet ‘historical’ is not fixed to any certain time period, but is subject to each country’s own perceptions. Often denoted ‘heirloom varieties’.

Instcode de WIEWS: Plus de 17 000 organisations nationales, régionales et internationales concernées par la conservation et l'utilisation durable des RPGAA ont été enregistrés par la FAO et ont reçu le INSTCODE de WIEWS. Le INSTCODE de WIEWS est un identifiant unique des organisations qui conservent le matériel génétique. Il est largement utilisé pour échanger des informations sur le matériel conservé ex situTélécharger la liste complète des INSTCODES de WIEWS. Un nouveau code peut être généré en ligne en communiquant avec le Point focal national dans votre pays ou à wiews@fao.org.

Medium-/Long-term conservation: Denotes the time-perspective in relation to germplasm conservation (c.f. FAO Genebank Standards, 2013).

Numéro d’accession: Un identifiant unique qui est attribué par le conservateur lorsque l’accession est entrée dans une banque de gènes. Cet identifiant ne doit jamais être attribué à une autre accession.

Orthodox seed: A seed that is tolerant to desiccation and can be stored at low temperatures (c.f. FAO Genebank Standards, 2013).

Plantes sous-exploitées: Plantes négligées mais apparemment utiles, sauvages ou domestiquées, qui ont un potentiel économique.

Population dynamics: The pattern of any process, or the interrelationship of factors, which affects growth or changes within a population, including birth and death rates, immigration/emigration, etc.

Population structure: Refers to the manner in which a population is built up, through sub-populations of age classes, allele frequencies, etc. A population without any explicit division into sub-populations is considered continuous. Any deviation from the ideally continuous population, e.g. through inbreeding or selection, results in a structured population.

Primary gene pool: The gene pool of similar or closely related species with which inter-crossing is easy, yielding fully fertile offspring. The most easily accessed genetic variability. The primary gene pool corresponds to the concept of biological species.

Ressources phytogénétiques pour l’alimentation et l’agriculture désigne le matériel génétique d’origine végétale ayant une valeur effective ou potentielle pour l’alimentation et l’agriculture (définition du Traité international sur les RPGAA, 2001).

Ruderal habitat: As mentioned in the context of the MCPD descriptor Collecting/acquisition source, it denotes a habitat that is characterized by frequent surface disturbance, either caused by human activities (e.g. construction sites or road edges) or by natural disturbance (e.g. fire).

Secondary gene pool: The gene pool of related species with which inter-crossing and gene transfer is possible, yielding hybrids and offspring that sometimes are fertile.

Taxon: Refers to a taxonomic category such as family, genus, species and possible infra-specific ranks (e.g. subspecies and botanical variety). 'Taxa' is the plural term of taxon.

Tertiary gene pool: The gene pool of distantly related species, or taxa, with which gene transfer is very difficult and which requires specialized techniques to produce hybrids. Resulting offspring is normally sterile and often lethal.