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Landrace refers to domesticated animals or plants adapted to the natural and cultural environment in which they live (or originated) and, in some cases, work. They often develop naturally with minimal assistance or guidance from humans using traditional breeding methods. Landraces differ somewhat from what is commonly termed a breed, and usually possess more diverse phenotypes and genotypes. They often form the basis of more highly-bred formalised breeds. Sometimes a formalised breed retains the "landrace" name, despite no longer being a true landrace.
Plants
Several definitions of the term landrace have been used in botanical application.
"Landrace populations are often highly variable in appearance, but they are each identifiable morphologically and have a certain genetic integrity. Farmers usually give them local names. A landrace has particular properties or characteristics. Some are considered early maturing and some late. Each has a reputation for adaptation to particular soil types according to the traditional peasant soil classifications, e.g. heavy or light, warm or cold, dry or wet, strong or weak. They also may be classified according to expected usage; among cereals, different landraces are used for flour, for porridge, for 'bulgur', and for malt to make beer, etc. All components of the population are adapted to local climatic conditions, cultural practices, and disease and pests."[1] But most important, they are genetically diverse (emphasis added). They are balanced populations - variable, in equilibrium with both environment and pathogens and genetically dynamic-.[2]
The term Landraces has additionally been defined as
"An autochthonous landrace is a variety with a high capacity to tolerate biotic and abiotic stress, resulting in a high yield stability and an intermediate yield level under a low input agricultural system."[3]
Evolutionary process
Nomenclature of cultigens based on evolutionary process. [4]
Landraces are grown from seeds (Wild species) which have not been systematically selected and marketed by seed companies or developed by plant breeders. Landraces will refer to all those cultigens that are highly heterogeneous, but with enough characteristics in common to permit their recognition as a group. This will include all cultigens cultivated without any specific nomenclature and value. A landrace identified with a unique feature and selected for uniformity over a period of time for maintenance of the characteristic features of the population can evolve into a farmers- variety or even a modern cultivar as in many crops; for example,Maruti in case of pigeonpea. [5]
Conversely,a modern cultivar grown over a time by the farmers and not maintained as per the principles of maintenance breeding can „evolve“ into a landrace. [6]
A significant proportion of the world-s farmers grow landraces. Data collected for a study of the spread of cereal agriculture into Europe showed that landraces have largely fallen out of use in Europe. European cereal landraces were mainly grown by our ancestors before plantbreeders started to improve the varieties in the 20th century.
But some landraces have survived in Europe having been handed on from one generation of farmers to the next. Elsewhere, landraces and traditional varieties have been revived by enthusiasts who seek to preserve our agricultural and food heritage. Landraces and traditional varieties are valued as the source of ingredients in traditional food and traditional drinks or as raw materials for thatching.[7]
There have been systematic efforts to preserve European cereal landraces either in germplasm collections or in situ. The activities of these collections are coordinated by the Biodiversity International. This organisation coordinates information on conservation activities, including a searchable online database of germplasm collections.
The terms -landrace- and -traditional variety- are sometimes used interchangeably.
External links
Multimedia
Animals
Landrace dogs
For example, landrace dogs are very different depending on their origins and purpose; Border Collies derive from a landrace in Scotland and northern England, where their primary characteristics had to do with how they herded sheep in the borderlands, and Salukis were a landrace breed in the Middle East where they chased game across open tracts of land. A landrace does not imply so much a breed as a type; for example, Border Collies traditionally have had a variation in appearance, from upright prick ears to nearly drop ears, different fullnesses of coat, and so on, although the general appearance was such that they could still be recognized as Border Collies and their performance around sheep most accurately represented their membership in that race.
Often, when people move to create a highly consistent purebred breed, focus is placed more on consistency of appearance rather than on consistency of behavior or adaptability to the environment, and much of what made the animals a landrace is lost. For example, show Border Collies might not be particularly good at herding sheep and might not have a coat that is appropriate for the Scottish borderlands; similarly, Salukis might not be able to chase and catch hares in the desert.
Other animals
Landraces include many local types of domestic animals: for example Shetland sheep, Welsh Mountain sheep, New Forest pony, Coloured Cob and Exmoor pony. Often (as in each of these examples) selections have been made from the landrace population to create formal pedigree breeds as well - for example, the New Forest ponies living semi-wild on the New Forest are mainly non-pedigree, landrace animals, while those kept as fully domesticated animals and bred for showing are a formal breed.
"Landrace" pigs (such as Danish Landrace) are in fact breeds derived from earlier true landraces.
A few horse breeds are claimed by aficionados to be "pure" and virtually unchanged from their original wild prototype or earliest landraces, though the term is rarely used in modern horse breeding. However, both the Arabian horse and the Andalusian horse make claims of great antiquity for the ancestry of their respective breeds.
External links
See also
References
- ^ Harlan, J.R., Crops and Man, American Society of Agronomy and Crop Science Society of America, Madison, Wisconsin, 1975
- ^ Harlan, J. R., Science, 1975, 174, 468-474.
- ^ Zeven, A.C. (1998). "Landraces: A review of definitions and classifications". Euphytica 104 (2): 127-139. doi:10.1023/A:1018683119237.
- ^ CURRENT SCIENCE, VOL. 91, NO. 11, 10 DECEMBER 2006
- ^ Ramanandan, P., Pigeonpea: Genetic Resources,In The Pigeonpea (eds Nene, Y.L.), CAB International, Wallingford, UK,1997, pp. 89-116.
- ^ Friis-Hansen, E. and Sthapit, B., Participatory Approaches to the Conservation and use of Plant Genetic Resources, International Plant Genetic Resources Institute,Rome, Italy, 2000, p. 199.
- ^ http://www.niab.com/research/pgbe/genetics/diversity-genomics-group/research/projects/landraces.html
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