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56-399: The A E Watkins Landrace Wheat Collection is a collection of heritage ( landrace ) varieties of wheat from around the world which are adapted to their local growing environment, the collection was collected in the 1930s and contains materials from 32 countries. The genetic diversity of the wheat in the collection is greater than found in modern varieties, and so this historical collection

112-581: A breed-standard appearance but might have lost other useful characteristics and have developed undesirable traits linked to inbreeding. The ancient landrace dogs of the Fertile Crescent that led to the Saluki breed excels in running down game across open tracts of hot desert, but conformation -bred individuals of the breed are not necessarily able to chase and catch desert hares . Some standardized breeds that are derived from landraces include

168-403: A broader scale, New World populations derived from the founder stock of Colonial Spanish horse . The Yakutian and Mongolian Horses of Asia have "unimproved" characteristics. The standardized swine breeds named "Landrace" are often not actually landraces or derived from landraces. The Danish Landrace pig breed, pedigreed in 1896 from an actual local landrace, is the principal ancestor of

224-405: A certain population, causing many individuals from said population to die due to not being adapted to this new pressure. The individuals that are better adapted to this new pressure will survive and reproduce at a higher rate than those who are at a disadvantage. This occurs over many generations until the population as a whole is better adapted to the pressure. This is natural selection at work, but

280-403: A decline in wingspan of living swallow populations, while also noting a decrease in the number of cliff swallows killed by passing cars. Those cliff swallows that were killed by passing cars showed a larger wingspan than the population as a whole. Confounding effects such as road usage, car size, and population size were shown to have no impact on the study. Evolutionary pressure imposed by humans

336-453: A different species (horizontal gene transmission). Because of this, the drug resistance increases over generations. For example, in hospitals, environments are created where pathogens such as C . difficile have developed a resistance to antibiotics. Antibiotic resistance is made worse by the misuse of antibiotics. Antibiotic resistance is encouraged when antibiotics are used to treat non-bacterial diseases, and when antibiotics are not used for

392-718: A dog landrace with a related standardized breed with a similar name is the collie . The Scotch Collie is a landrace, while the Rough Collie and the Border Collie are standardized breeds. They can be very different in appearance, though the Rough Collie in particular was developed from the Scotch Collie by inbreeding to fix certain highly desired traits. In contrast to the landrace, in the various standardized Collie breeds, purebred individuals closely match

448-415: A farmers' variety or cultivar . Traits from landraces are valuable for incorporation into elite lines . Crop disease resistance genes from landraces can provide eternally-needed resistances to more widely-used, modern varieties. Some standardized animal breeds originate from attempts to make landraces more consistent through selective breeding , and a landrace may become a more formal breed with

504-406: A focus on their production may result in missing out on some benefits afforded to producers of genetically selected and homogenous organisms, including breeders' rights legislation, easier availability of loans and other business services, even the right to share seed or stock with others, depending on how favorable the laws in the area are to high-yield agribusiness interests. As Regine Andersen of

560-457: A group. These characteristics are used by farmers to manage diversity and purity within landraces. In some cultures, the development of new landraces is typically limited to members of specific social groups, such as women or shaman. Maintaining existing landraces, like developing new landraces, requires that farmers be able to identify crop-specific characteristics and that those characteristics are passed on to following generations. Over time,

616-429: A landrace and a cultivar, may also include landraces when referring to plant varieties not subjected to formal breeding programs. A landrace native to, or produced for a long time within the agricultural system in which it is found is referred to as an autochthonous landrace , while a more recently introduced one is termed an allochthonous landrace . Within academic agronomy , the term autochthonous landrace

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672-511: A landrace is a mixture of phenotypic forms despite relative outward uniformity, and a great adaptability to its natural and human environment. The word landrace entered non-academic English in the early 1930s, by way of the Danish Landrace pig , a particular breed of lop-eared swine. Many other languages do not use separate terms, like landrace and breed , but instead rely on extended description to convey such distinctions. Spanish

728-782: A landrace. General features that characterize a landrace may include: Landrace literally means 'country-breed' (German: Landrasse ) and close cognates of it are found in various Germanic languages . The first known reference to the role of landraces as genetic resources was made in 1890 at an agriculture and forestry congress in Vienna , Austria . The term was first defined by Kurt von Rümker in 1908, and more clearly described in 1909 by U. J. Mansholt, who wrote that landraces have more stable characteristics and better resistance to adverse conditions, but have lower production capacity than cultivars, and are apt to change genetically when moved to another environment. H. Kiessling added in 1912 that

784-565: A portfolio of landraces over time that have specific ecological niches and uses. Conversely, modern cultivars can also be developed into a landrace over time when farmers save seed and practice selective breeding . Although landraces are often discussed once they have become endemic to a particular geographical region, landraces have always been moved over long and short distances. Some landraces can adapt to various environments, while others only thrive within specific conditions. Self-fertilizing and vegetatively populated species adapt by changing

840-562: A reduction in biodiversity , because most of the genetic diversity of domesticated plant species lies in landraces and other traditionally used varieties. Some farmers using scientifically improved varieties also continue to raise landraces for agronomic reasons that include better adaptation to the local environment, lower fertilizer requirements, lower cost, and better disease resistance. Cultural and market preferences for landraces include culinary uses and product attributes such as texture, color, or ease of use. Plant landraces have been

896-471: A separate study also showed behavioral differences, with older females displaying the timid behavior that one would expect from this selection. Since the domestication of dogs , they have evolved alongside humans due to pressure from humans and the environment. This began by humans and wolves sharing the same area, with a pressure to coexist eventually leading to their domestication. Evolutionary pressure from humans led to many different breeds that paralleled

952-408: A significant loss of genetic diversity, including resilience traits. The Watkins wheat collection is now being explored for potential genetic resistance to aphids and wheat bulb fly eyespot resistance tan spot, Stagonospora nodorum blotch (SNB) and Fusarium head blight . The collection is also being explored as a source of genetic diversity for traits like Starch Digestibility. The collection

1008-547: A standardized or formal breed. Two approaches have been used to conserve plant landraces: As the amount of agricultural land dedicated to growing landrace crops declines, such as in the example of wheat landraces in the Fertile Crescent , landraces can become extinct in cultivation. Therefore ex situ landrace conservation practices are considered a way to avoid losing the genetic diversity completely. Research published in 2020 suggested that existing ways of cataloging diversity within ex situ genebanks fall short of cataloging

1064-565: A strict programme of genetic isolation and formal artificial selection to achieve a particular phenotype." In various domestic species (including pigs, goats, sheep and geese) some standardized breeds include "Landrace" in their names, but do not meet widely used definitions of landraces. For example, the British Landrace pig is a standardized breed, derived from earlier breeds with "Landrace" names. Farmers' variety , usually applied to local cultivars, or seen as intermediate between

1120-538: A threat to patients in hospitals, who are immunocompromised from illness or antibiotic treatment. Virulence factors are the characteristics that the evolved bacteria have developed to increase pathogenicity. One of the virulence factors of C . difficile that largely constitutes its resistance to antibiotics is its toxins: enterotoxin TcdA and cytotoxin TcdB. Toxins produce spores that are difficult to inactivate and remove from

1176-477: A variety of topics, including The Origin of Cultivated Plants , Heredity and Evolution, and The Wheat Species; a Critique by A.E. Watkins . Landrace A significant proportion of farmers around the world grow landrace crops , and most plant landraces are associated with traditional agricultural systems. Landraces of many crops have probably been grown for millennia. Increasing reliance upon modern plant cultivars that are bred to be uniform has led to

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1232-431: Is a constant battle for evolutionary advantages in outcompeting each other. The evolutionary arms race between the rapidly evolving virulence factors of the bacteria and the treatment practices of modern medicine requires evolutionary biologists to understand the mechanisms of resistance in these pathogenic bacteria, especially considering the growing number of infected hospitalized patients. The evolved virulence factors pose

1288-442: Is a major cause of death by nosocomial infections. When symbiotic gut flora populations are disrupted (e.g., by antibiotics ), one becomes more vulnerable to pathogens. The rapid evolution of antibiotic resistance places an enormous selective pressure on the advantageous alleles of resistance passed down to future generations. The Red Queen hypothesis shows that the evolutionary arms race between pathogenic bacteria and humans

1344-414: Is a major health concern, because the condition grants some resistance to this infectious disease. Just as with the development of antibiotic resistance in bacteria, resistance to pesticides and herbicides has begun to appear with commonly used agricultural chemicals . For example: Human activity can lead to unintended changes in the environment. The human activity will have a possible negative effect on

1400-506: Is also seen in elk populations. These studies do not look at morphological differences, but behavioral differences. Faster and more mobile male elk were shown to be more likely to fall prey to hunters. The hunters create an environment where the more active animals are more likely to succumb to predation than less active animals. Female elk who survived past two years, would decrease their activity as each year passed, leaving more shy female elk that were more likely to survive. Female elk in

1456-821: Is at the heart of the International Treaty on Plant Genetic Resources for Food and Agriculture (the "Plant Treaty" for short), under the Food and Agriculture Organization of the United Nations (FAO), though its concerns are not exclusively limited to landraces. Landraces played a basic role in the development of the standardized breeds but are today threatened by the market success of the standardized breeds. In developing countries, landraces still play an important role, especially in traditional production systems. Specimens within an animal landrace tend to be genetically similar, though more diverse than members of

1512-679: Is being explored as a source of genetic diversity for key traits, such as disease resistance. The collection is now stored within the Germplasm Resources Unit at the John Innes Centre in Norwich . The Watkins Landrace Wheat Collection is a unique resource due to the historical nature of being collected in the 1930’s before widespread globalisation of trade, and before intensive selective breeding in wheat to develop high-yielding elite varieties , which resulted in

1568-500: Is commonly attributed to selective pressure by humans, who often kill the snakes when they are discovered. Non-rattling snakes are more likely to go unnoticed, so survive to reproduce offspring that, like themselves, are less likely to rattle. Populations of cliff swallows in Nebraska have displayed morphological changes in their wings after many years of living next to roads. Collecting data for over 30 years, researchers noticed

1624-518: Is due to the transcriptional co-regulation of two adjacent genes in Eukaryota . Drug resistance in bacteria is an example of an outcome of natural selection . When a drug is used on a species of bacteria, those that cannot resist die and do not produce offspring, while those that survive potentially pass on the resistance gene to the next generation (vertical gene transmission). The resistance gene can also be passed on to one bacterium by another of

1680-609: Is exerted by factors that reduce or increase reproductive success in a portion of a population, driving natural selection . It is a quantitative description of the amount of change occurring in processes investigated by evolutionary biology , but the formal concept is often extended to other areas of research. In population genetics , selective pressure is usually expressed as a selection coefficient . It has been shown that putting an amino acid bio-synthesizing gene like HIS4 gene under amino acid selective pressure in yeast causes enhancement of expression of adjacent genes which

1736-539: Is named after the botanist Arthur Ernest Watkins , who was the first scientist to determine the number of chromosomes in wheat, but also spearheaded the collection efforts and recognised the importance of having genetic material from all around the world. Arthur Ernest Watkins (April 23rd 1898 - January 3rd 1967), was awarded a Diploma in Agriculture from the University of Cambridge in 1922. In 1924, he joined

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1792-607: Is one such language. Geneticist D. Phillip Sponenberg described animal breeds within these classes: the landrace, the standardized breed, modern "type" breeds, industrial strains, and feral populations. He describes landraces as an early stage of breed development, created by a combination of founder effect , isolation, and environmental pressures. Human selection for production goals is also typical of landraces. As discussed in more detail in breed , that term itself has several definitions from various scientific and animal husbandry perspectives. Some of those senses of breed relate to

1848-698: Is sometimes used with a more technical, productivity-related definition, synthesized by A. C. Zeven from previous definitions beginning with Mansholt's: "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." The terms autochthonous and allochthonous are most often applied to plants, with animals more often being referred to as indigenous or native . Examples of references in sources to long-term local landraces of livestock include constructions such as "indigenous landraces of sheep", and "Leicester Longwool sheep were bred to

1904-667: The American Landrace (1930s). In this way, the Swedish Landrace is derived from the Danish and from other Scandinavian breeds, as is the British Landrace breed. Many standardized goose breeds named "Landrace", e.g. the Twente Landrace goose , are not actually true landraces, but may be derived from them. Evolutionary pressure Evolutionary pressure , selective pressure or selection pressure

1960-805: The Dutch Landrace , Swedish Landrace and Finnish Landrace goats . The Danish Landrace is a modern mix of three different breeds, one of which was a "Landrace"-named breed. The wild progenitor of the domestic horse is extinct. It is rare for landraces among domestic horses to remain isolated, due to human use of horses for transportation, thus causing horses to move from one local population to another. The heavy 'draft' type of domestic horse, developed in Europe, has differentiated into many separate landraces or breeds. Examples of horse landraces also include insular populations in Greece and Indonesia, and, on

2016-602: The National Institute of Agricultural Botany (NIAB, UK). However, more may need to be done, because plant genetic variety, the source of crop health and seed quality, depends on a diversity of landraces and other traditionally used varieties. Efforts (as of 2008 ) were mostly focused on Iberia , the Balkans , and European Russia , and dominated by species from mountainous areas. Despite their incompleteness, these efforts have been described as "crucial in preventing

2072-763: The Plant Breeding Institute , and in 1931 was appointed as a lecturer in Cytology at the University of Cambridge’s Faculty of Agriculture and was a member of the Genetical Society . A E Watkins worked alongside Dr Harold Howard , who would later lead a research group to develop the Maris Piper variety of potato, which was the first potato bred to be resistant to potato cyst nematodes . Watkins also wrote multiple books and papers on

2128-598: The Turkish Angora and Turkish Van breeds and their possible derivation from the Van cat landrace, the relationships are not entirely clear. Dog landraces and the selectively bred dog breeds that follow breed standards vary widely depending on their origins and purpose. Landraces are distinguished from dog breeds which have breed standards, breed clubs and registries. Landrace dogs have more variety in their appearance than do standardized dog breeds. An example of

2184-565: The Fridtjof Nansen Institute (Norway) and the Farmers' Rights Project puts it, "Agricultural biodiversity is being eroded. This trend is putting at risk the ability of future generations to feed themselves. In order to reverse the trend, new policies must be implemented worldwide. The irony of the matter is that the poorest farmers are the stewards of genetic diversity." Protecting farmer interests and protecting biodiversity

2240-560: The International Agricultural Congress, organized by the predecessor of the FAO, an extensive discussion was held on the need to conserve landraces. A recommendation that members organize nation-by-nation landrace conservation did not succeed in leading to widespread conservation efforts. Landraces are often free from many intellectual property and other regulatory encumbrances. However, in some jurisdictions,

2296-498: The appropriate information for landrace crops. An in situ conservation effort to save the Berrettina di Lungavilla squash landrace made use of participatory plant breeding practices in order to incorporate the local community into the work. Preservation efforts for cereal strains are ongoing including in situ and in online-searchable germplasm collections ( seed banks ), coordinated by Biodiversity International and

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2352-410: The concept of landraces. A Food and Agriculture Organization of the United Nations (FAO) guideline defines landrace and landrace breed as "a breed that has largely developed through adaptation to the natural environment and traditional production system in which it has been raised." This is in contrast to its definition of a standardized breed : "a breed of livestock that was developed according to

2408-742: The creation of a breed registry or publication of a breed standard . In such a case, one may think of the landrace as a "stage" in breed development. However, in other cases, formalizing a landrace may result in the genetic resource of a landrace being lost through crossbreeding . While many landrace animals are associated with farming, other domestic animals have been put to use as modes of transportation, as companion animals , for sporting purposes, and for other non-farming uses, so their geographic distribution may differ. For example, horse landraces are less common because human use of them for transport has meant that they have moved with people more commonly and constantly than most other domestic animals, reducing

2464-470: The environment are necessary practices in health facilities. The virulence of this pathogen is remarkable and may take a radical change at sanitation approaches used in hospitals to control CDI outbreaks. The malaria parasite can exert a selective pressure on human populations. This pressure has led to natural selection for erythrocytes carrying the sickle cell hemoglobin gene mutation ( Hb S)—causing sickle cell anaemia —in areas where malaria

2520-509: The environment. This is especially true in hospitals where an infected patient's room may contain spores for up to 20 weeks. Combating the threat of the rapid spread of CDIs is therefore dependent on hospital sanitation practices removing spores from the environment. A study published in the American Journal of Gastroenterology found that to control the spread of CDIs glove use, hand hygiene, disposable thermometers and disinfection of

2576-424: The extinction of many of these local ecotypes". An agricultural study published in 2008 showed that landrace cereal crops began to decline in Europe in the 19th century such that cereal landraces "have largely fallen out of use" in Europe. Landrace cultivation in central and northwest Europe was almost eradicated by the early 20th century, due to economic pressure to grow improved, modern cultivars. While many in

2632-418: The frequencies of phenotypes. Outbreeding crops absorb new genotypes through intentional and unintentional hybridization, or through mutation. A clear example of vegetal landrace would consist in the diverse adaptations of wheat to differential artificial selection constraints. Members of a landrace variety, selected for uniformity with regards to a unique feature over a period of time, can be developed into

2688-400: The incidence of populations locally genetically isolated for extensive periods of time. Many standardized breeds have rather recently (within a century or less) been derived from landraces. Examples, often called natural breeds , include Arabian Mau , Egyptian Mau , Korat , Kurilian Bobtail , Maine Coon , Manx , Norwegian Forest Cat , Siberian , and Siamese . In some cases, such as

2744-644: The native landraces of the region". Some usage of autochthonous does occur in reference to livestock, e.g. "autochthonous races of cattle such as the Asturian mountain cattle – Ratina and Casina – and Tudanca cattle." A significant proportion of farmers around the world grow landrace crops . However, as industrialized agriculture spreads, cultivars , which are selectively bred for high yield, rapid growth, disease and drought resistance, and other commercial production values, are supplanting landraces, putting more and more of them at risk of extinction . In 1927 at

2800-433: The needs of the time, whether it was a need for protecting livestock or assisting in the hunt. Hunting and herding were a couple of the first reasons for humans artificially selecting for traits they deemed beneficial. This selective breeding does not stop there, but extends to humans selecting for certain traits deemed desirable in their domesticated dogs, such as size and color, even if they are not necessarily beneficial to

2856-413: The prescribed amount of time or in the prescribed dose. Antibiotic resistance may arise out of standing genetic variation in a population or de novo mutations in the population. Either pathway could lead to antibiotic resistance, which may be a form of evolutionary rescue . Clostridioides difficile , gram-positive bacteria species that inhabits the gut of mammals, exemplifies one type of bacteria that

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2912-507: The pressure is coming from man-made activity such as building roads or hunting. This is seen in the below examples of cliff swallows and elk. However, not all human activity that causes an evolutionary pressure happens unintentionally. This is demonstrated in dog domestication and the subsequent selective breeding that resulted in the various breeds known today. In more heavily (human) populated and trafficked areas, reports have been increasing of rattlesnakes that do not rattle. This phenomenon

2968-402: The process of identifying the distinguishing characteristic or features of a new landrace is reinforced by cultivation processes; for example, descendants of a plant that is notably drought tolerant may become iteratively more so through selective breeding as farmers regard it as better for dry areas and prioritize planting it in those locations. This is one way in which farming systems can develop

3024-509: The region are already extinct, some have survived by being passed from generation to generation, and have also been revived by enthusiasts outside Europe to preserve European agriculture and food culture elsewhere. These survivals are usually for specific uses, such as thatch , and traditional European cuisine and craft beer brewing. The label landrace includes regional cultigens that are genetically heterogeneous , but with enough characteristics in common to permit their recognition as

3080-477: The specific criteria which describe landraces, although there is broad consensus about the existence and utility of the classification. Individual criteria may be weighted differently depending on a given source's focus (e.g., governmental regulation , biological sciences , agribusiness , anthropology and culture, environmental conservation , pet -keeping and -breeding , etc.). Additionally, not all cultivars agreed to be landraces exhibit every characteristic of

3136-662: The subject of more academic research, and the majority of academic literature about landraces is focused on botany in agriculture , not animal husbandry . Animal landraces are distinct from ancestral wild species of modern animal stock, and are also distinct from separate species or subspecies derived from the same ancestor as modern domestic stock. Not all landraces derive from wild or ancient animal stock; in some cases, notably dogs and horses, domestic animals have escaped in sufficient numbers in an area to breed feral populations that form new landraces through evolutionary pressure . There are differences between authoritative sources on

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