WIEWS - World Information and Early Warning System on Plant Genetic Resources for Food and Agriculture


Accession: A distinct, uniquely identifiable sample of seeds representing a cultivar, breeding line or a population, which is maintained in storage for conservation and use. 

Accession number: A unique identifier that is assigned by the curator when an accession is entered into a gene bank. This identifier should never be assigned to another accession.

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 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.

Core collection: A subset selected to contain the maximum available variation in a small number of accessions.

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.

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

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

Plant Genetic Resources for Food and Agriculture (PGRFA): Any genetic material of plant origin of actual or potential value for food and agriculture (definition from the International Treaty on PGRFA, 2001).

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.

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.

Under-utilized plants: Neglected but seemingly useful plants, wild or domesticated, that have economic potential.

WIEWS instcode: More than 17,000 national, regional and international institutes and organizations dealing with the conservation and sustainable use of PGRFA have been registered by FAO and assigned a WIEWS INSTCODE. The WIEWS INSTCODE is used worldwide in the exchange of information about germplasm conserved as unique identifier for the germplasm holding organization. Download the complete list of WIEWS INSTCODES. A new WIEWS INSTCODE can  be generated online by contacting your country National Focal Point or [email protected].