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110-610: In the beginning the Tallán lived in behetrias , which were simple settlements without a head or an organization, in which all its members were engaged in the same and unique activity, mainly agriculture and fishing . Then through barter with the neighboring partialities they obtained what was necessary to live. This need for others to subsist allowed the Chimúes first and then the Incas to impose their dominion over them. Although due to

220-810: A lord of the manor with a Roman Catholic church and priest. Thanks to the exchange with the Al-Andalus where the Arab Agricultural Revolution was underway, European agriculture transformed, with improved techniques and the diffusion of crop plants, including the introduction of sugar, rice, cotton and fruit trees (such as the orange). After 1492, the Columbian exchange brought New World crops such as maize, potatoes, tomatoes, sweet potatoes , and manioc to Europe, and Old World crops such as wheat, barley, rice, and turnips , and livestock (including horses, cattle, sheep and goats) to

330-568: A better cost/benefit ratio than non-participatory approaches, and suggested incorporating participatory plant breeding with evolutionary plant breeding. Evolutionary plant breeding describes practices which use mass populations with diverse genotypes grown under competitive natural selection. Survival in common crop cultivation environments is the predominant method of selection, rather than direct selection by growers and breeders. Individual plants that are favored under prevailing growing conditions, such as environment and inputs, contribute more seed to

440-470: A combination of labor supply and labor demand trends have driven down the share of population employed in agriculture. During the 16th century in Europe, between 55 and 75% of the population was engaged in agriculture; by the 19th century, this had dropped to between 35 and 65%. In the same countries today, the figure is less than 10%. At the start of the 21st century, some one billion people, or over 1/3 of

550-407: A cross of related species or genera that do not normally sexually reproduce with each other. These crosses are referred to as Wide crosses . For example, the cereal triticale is a wheat and rye hybrid. The cells in the plants derived from the first generation created from the cross contained an uneven number of chromosomes and as a result was sterile. The cell division inhibitor colchicine

660-555: A fertilizer for crops. Plant breeding Plant breeding is the science of changing the traits of plants in order to produce desired characteristics. It is used to improve the quality of plant products for use by humans and animals. The goals of plant breeding are to produce crop varieties that boast unique and superior traits for a variety of applications. The most frequently addressed agricultural traits are those related to biotic and abiotic stress tolerance, grain or biomass yield, end-use quality characteristics such as taste or

770-462: A few varieties that became dominant in some locations almost disappeared in others; poorly-adapted varieties disappeared everywhere. Evolutionary breeding populations have been used to establish self-regulating plant–pathogen systems. Examples include barley, where breeders were able to improve resistance to Rynchosporium secalis scald over 45 generations. An evolutionary breeding project grew F5 hybrid bulk soybean populations on soil infested by

880-469: A growing European mutiny over genetically modified crops by banning the planting of a widely grown pest-resistant corn variety. " The debate encompasses the ecological impact of genetically modified plants , the safety of genetically modified food and concepts used for safety evaluation like substantial equivalence . Such concerns are not new to plant breeding. Most countries have regulatory processes in place to help ensure that new crop varieties entering

990-664: A hazardous industry, and farmers worldwide remain at high risk of work-related injuries, lung disease, noise-induced hearing loss , skin diseases, as well as certain cancers related to chemical use and prolonged sun exposure. On industrialized farms , injuries frequently involve the use of agricultural machinery , and a common cause of fatal agricultural injuries in developed countries is tractor rollovers . Pesticides and other chemicals used in farming can be hazardous to worker health , and workers exposed to pesticides may experience illness or have children with birth defects. As an industry in which families commonly share in work and live on

1100-444: A high use of inputs (water, fertilizer, pesticide and automation). It is practiced mainly in developed countries. From the twentieth century onwards, intensive agriculture increased crop productivity. It substituted synthetic fertilizers and pesticides for labor, but caused increased water pollution, and often involved farm subsidies. Soil degradation and diseases such as stem rust are major concerns globally; approximately 40% of

1210-605: A plant are what determine what type of qualitative or quantitative traits it will have. Plant breeders strive to create a specific outcome of plants and potentially new plant varieties, and in the course of doing so, narrow down the genetic diversity of that variety to a specific few biotypes. It is practiced worldwide by individuals such as gardeners and farmers, and by professional plant breeders employed by organizations such as government institutions, universities, crop-specific industry associations or research centers. International development agencies believe that breeding new crops

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1320-444: A plant with the desired trait or traits faster than classical breeding because the majority of the plant's genome is not altered. To genetically modify a plant, a genetic construct must be designed so that the gene to be added or removed will be expressed by the plant. To do this, a promoter to drive transcription and a termination sequence to stop transcription of the new gene, and the gene or genes of interest must be introduced to

1430-447: A positive note, the gender gap in access to mobile internet in low- and middle-income countries fell from 25 percent to 16 percent between 2017 and 2021, and the gender gap in access to bank accounts narrowed from 9 to 6 percentage points. Women are as likely as men to adopt new technologies when the necessary enabling factors are put in place and they have equal access to complementary resources. Agriculture, specifically farming, remains

1540-404: A significant decrease in genetic diversity and resources among livestock breeds, leading to a corresponding decrease in disease resistance and local adaptations previously found among traditional breeds. Grassland based livestock production relies upon plant material such as shrubland , rangeland , and pastures for feeding ruminant animals. Outside nutrient inputs may be used, however manure

1650-492: A small area of forest is cleared by cutting and burning the trees. The cleared land is used for growing crops for a few years until the soil becomes too infertile, and the area is abandoned. Another patch of land is selected and the process is repeated. This type of farming is practiced mainly in areas with abundant rainfall where the forest regenerates quickly. This practice is used in Northeast India, Southeast Asia, and

1760-406: A technique called chromosome engineering may also be used. When a desirable trait has been bred into a species, a number of crosses to the favored parent are made to make the new plant as similar to the favored parent as possible. Returning to the example of the mildew resistant pea being crossed with a high- yielding but susceptible pea, to make the mildew resistant progeny of the cross most like

1870-566: A whole plant. Such a method is referred to as embryo rescue . This technique has been used to produce new rice for Africa , an interspecific cross of Asian rice Oryza sativa and African rice O. glaberrima . Hybrids may also be produced by a technique called protoplast fusion. In this case protoplasts are fused, usually in an electric field. Viable recombinants can be regenerated in culture. Chemical mutagens like ethyl methanesulfonate (EMS) and dimethyl sulfate (DMS), radiation , and transposons are used for mutagenesis . Mutagenesis

1980-552: A year, or requiring irrigation. In all of these environments perennial crops are grown (coffee, chocolate) and systems are practiced such as agroforestry . In temperate environments, where ecosystems were predominantly grassland or prairie , highly productive annual farming is the dominant agricultural system. Important categories of food crops include cereals, legumes, forage, fruits and vegetables. Natural fibers include cotton, wool , hemp , silk and flax . Specific crops are cultivated in distinct growing regions throughout

2090-473: A yearly summit to discuss safety. Overall production varies by country as listed. The twenty largest countries by agricultural output (in nominal terms) at peak level as of 2018, according to the IMF and CIA World Factbook . Cropping systems vary among farms depending on the available resources and constraints; geography and climate of the farm; government policy; economic, social and political pressures; and

2200-584: Is a hybrid of a Chilean and a North American species, developed by breeding in Europe and North America. The indigenous people of the Southwest and the Pacific Northwest practiced forest gardening and fire-stick farming . The natives controlled fire on a regional scale to create a low-intensity fire ecology that sustained a low-density agriculture in loose rotation; a sort of "wild" permaculture . A system of companion planting called

2310-425: Is achieved by adding a specific gene or genes to a plant, or by knocking down a gene with RNAi , to produce a desirable phenotype . The plants resulting from adding a gene are often referred to as transgenic plants . If for genetic modification genes of the species or of a crossable plant are used under control of their native promoter, then they are called cisgenic plants . Sometimes genetic modification can produce

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2420-453: Is also known as molecular breeding . Sometimes many different genes can influence a desirable trait in plant breeding. The use of tools such as molecular markers or DNA fingerprinting can map thousands of genes. This allows plant breeders to screen large populations of plants for those that possess the trait of interest. The screening is based on the presence or absence of a certain gene as determined by laboratory procedures, rather than on

2530-582: Is an important and controversial issue. Production of new varieties is dominated by commercial plant breeders, who seek to protect their work and collect royalties through national and international agreements based in intellectual property rights . The range of related issues is complex. In the simplest terms, critics of the increasingly restrictive regulations argue that, through a combination of technical and economic pressures, commercial breeders are reducing biodiversity and significantly constraining individuals (such as farmers) from developing and trading seed on

2640-626: Is both a cause of and sensitive to environmental degradation , such as biodiversity loss , desertification , soil degradation , and climate change , all of which can cause decreases in crop yield. Genetically modified organisms are widely used, although some countries ban them . The word agriculture is a late Middle English adaptation of Latin agricultūra , from ager 'field' and cultūra ' cultivation ' or 'growing'. While agriculture usually refers to human activities, certain species of ant , termite and beetle have been cultivating crops for up to 60 million years. Agriculture

2750-423: Is broader, covering molecular biology , cytology , systematics , physiology , pathology , entomology , chemistry , and statistics ( biometrics ). It has also developed its own technology. One major technique of plant breeding is selection , the process of selectively propagating plants with desirable characteristics and eliminating or "culling" those with less desirable characteristics. Another technique

2860-444: Is defined with varying scopes, in its broadest sense using natural resources to "produce commodities which maintain life, including food, fiber, forest products, horticultural crops, and their related services". Thus defined, it includes arable farming , horticulture, animal husbandry and forestry , but horticulture and forestry are in practice often excluded. It may also be broadly decomposed into plant agriculture , which concerns

2970-684: Is important for ensuring food security by developing new varieties that are higher yielding, disease resistant, drought tolerant or regionally adapted to different environments and growing conditions. A recent study shows that without plant breeding, Europe would have produced 20% fewer arable crops over the last 20 years, consuming an additional 21.6 million hectares (53 million acres) of land and emitting 4 billion tonnes (3.9 × 10 long tons; 4.4 × 10 short tons) of carbon. Wheat species created for Morocco are currently being crossed with plants to create new varieties for northern France. Soy beans, which were previously grown predominantly in

3080-416: Is one common cause of yield loss Genetic modification of plants that can produce pharmaceuticals (and industrial chemicals), sometimes called pharming , is a rather radical new area of plant breeding. The debate surrounding genetically modified food during the 1990s peaked in 1999 in terms of media coverage and risk perception, and continues today – for example, " Germany has thrown its weight behind

3190-438: Is returned directly to the grassland as a major nutrient source. This system is particularly important in areas where crop production is not feasible because of climate or soil, representing 30–40 million pastoralists. Mixed production systems use grassland, fodder crops and grain feed crops as feed for ruminant and monogastric (one stomach; mainly chickens and pigs) livestock. Manure is typically recycled in mixed systems as

3300-423: Is that the virus is not usually passed on to the progeny, so every plant has to be inoculated. The majority of commercially released transgenic plants are currently limited to plants that have introduced resistance to insect pests and herbicides . Insect resistance is achieved through incorporation of a gene from Bacillus thuringiensis (Bt) that encodes a protein that is toxic to some insects. For example,

3410-430: Is the deliberate interbreeding (crossing) of closely or distantly related individuals to produce new crop varieties or lines with desirable properties. Plants are crossbred to introduce traits / genes from one variety or line into a new genetic background. For example, a mildew -resistant pea may be crossed with a high-yielding but susceptible pea, the goal of the cross being to introduce mildew resistance without losing

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3520-440: Is the generation of mutants. The breeder hopes for desirable traits to be bred with other cultivars – a process known as mutation breeding . Classical plant breeders also generate genetic diversity within a species by exploiting a process called somaclonal variation , which occurs in plants produced from tissue culture, particularly plants derived from callus . Induced polyploidy , and the addition or removal of chromosomes using

3630-433: Is when farmers are involved in a crop improvement programme with opportunities to make decisions and contribute to the research process at different stages. Participatory approaches to crop improvement can also be applied when plant biotechnologies are being used for crop improvement. Local agricultural systems and genetic diversity are strengthened by participatory programs, and outcomes are enhanced by farmers knowledge of

3740-556: The Green Revolution increased crop production in the developing world in the 1960s. Following World War II a number of techniques were developed that allowed plant breeders to hybridize distantly related species, and artificially induce genetic diversity. When distantly related species are crossed, plant breeders make use of a number of plant tissue culture techniques to produce progeny from otherwise fruitless mating. Interspecific and intergeneric hybrids are produced from

3850-500: The Indus Valley civilization . In China, from the 5th century BC, there was a nationwide granary system and widespread silk farming . Water-powered grain mills were in use by the 1st century BC, followed by irrigation. By the late 2nd century, heavy ploughs had been developed with iron ploughshares and mouldboards . These spread westwards across Eurasia. Asian rice was domesticated 8,200–13,500 years ago – depending on

3960-583: The Paleolithic , after 10,000 BC. Staple food crops were grains such as wheat and barley, alongside industrial crops such as flax and papyrus . In India , wheat, barley and jujube were domesticated by 9,000 BC, soon followed by sheep and goats. Cattle, sheep and goats were domesticated in Mehrgarh culture by 8,000–6,000 BC. Cotton was cultivated by the 5th–4th millennium BC. Archeological evidence indicates an animal-drawn plough from 2,500 BC in

4070-514: The Tigris and Euphrates rivers and a canal system for irrigation. Ploughs appear in pictographs around 3,000 BC; seed-ploughs around 2,300 BC. Farmers grew wheat, barley, vegetables such as lentils and onions, and fruits including dates, grapes, and figs. Ancient Egyptian agriculture relied on the Nile River and its seasonal flooding. Farming started in the predynastic period at the end of

4180-400: The cotton bollworm , a common cotton pest, feeds on Bt cotton it will ingest the toxin and die. Herbicides usually work by binding to certain plant enzymes and inhibiting their action. The enzymes that the herbicide inhibits are known as the herbicide's " target site ". Herbicide resistance can be engineered into crops by expressing a version of target site protein that is not inhibited by

4290-630: The molecular clock estimate that is used – on the Pearl River in southern China with a single genetic origin from the wild rice Oryza rufipogon . In Greece and Rome , the major cereals were wheat, emmer, and barley, alongside vegetables including peas, beans, and olives. Sheep and goats were kept mainly for dairy products. In the Americas, crops domesticated in Mesoamerica (apart from teosinte) include squash, beans, and cacao . Cocoa

4400-548: The organic movement . Unsustainable farming practices in North America led to the Dust Bowl of the 1930s. Pastoralism involves managing domesticated animals. In nomadic pastoralism , herds of livestock are moved from place to place in search of pasture, fodder, and water. This type of farming is practiced in arid and semi-arid regions of Sahara , Central Asia and some parts of India. In shifting cultivation ,

4510-492: The soybean cyst nematode and was able to increase the proportion of resistant plants from 5% to 40%. The International Center for Agricultural Research in the Dry Areas (ICARDA) evolutionary plant breeding is combined with participatory plant breeding in order to allow farmers to choose which varieties suit their needs in their local environment. An influential 1956 effort by Coit A. Suneson to codify this approach coined

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4620-540: The Amazon Basin. Subsistence farming is practiced to satisfy family or local needs alone, with little left over for transport elsewhere. It is intensively practiced in Monsoon Asia and South-East Asia. An estimated 2.5 billion subsistence farmers worked in 2018, cultivating about 60% of the earth's arable land . Intensive farming is cultivation to maximize productivity, with a low fallow ratio and

4730-560: The Americas. Irrigation , crop rotation , and fertilizers advanced from the 17th century with the British Agricultural Revolution , allowing global population to rise significantly. Since 1900, agriculture in developed nations, and to a lesser extent in the developing world, has seen large rises in productivity as mechanization replaces human labor, and assisted by synthetic fertilizers , pesticides, and selective breeding . The Haber-Bosch method allowed

4840-586: The Paleolithic Levant, 23,000 years ago, cereals cultivation of emmer , barley , and oats has been observed near the sea of Galilee. Rice was domesticated in China between 11,500 and 6,200 BC with the earliest known cultivation from 5,700 BC, followed by mung , soy and azuki beans. Sheep were domesticated in Mesopotamia between 13,000 and 11,000 years ago. Cattle were domesticated from

4950-486: The Three Sisters was developed in North America. The three crops were winter squash , maize, and climbing beans. Indigenous Australians , long supposed to have been nomadic hunter-gatherers , practiced systematic burning, possibly to enhance natural productivity in fire-stick farming. Scholars have pointed out that hunter-gatherers need a productive environment to support gathering without cultivation. Because

5060-793: The United Nations (FAO) posits that the roles and responsibilities of women in agriculture may be changing – for example, from subsistence farming to wage employment, and from contributing household members to primary producers in the context of male-out-migration. In general, women account for a greater share of agricultural employment at lower levels of economic development, as inadequate education, limited access to basic infrastructure and markets, high unpaid work burden and poor rural employment opportunities outside agriculture severely limit women's opportunities for off-farm work. Women who work in agricultural production tend to do so under highly unfavorable conditions. They tend to be concentrated in

5170-524: The United States is roughly 1.7 times more productive than it was in 1948. Agriculture employed 873 million people in 2021, or 27% of the global workforce, compared with 1 027 million (or 40%) in 2000. The share of agriculture in global GDP was stable at around 4% since 2000–2023. Despite increases in agricultural production and productivity, between 702 and 828 million people were affected by hunger in 2021. Food insecurity and malnutrition can be

5280-544: The annual work-related death toll among agricultural employees is at least 170,000, twice the average rate of other jobs. In addition, incidences of death, injury and illness related to agricultural activities often go unreported. The organization has developed the Safety and Health in Agriculture Convention, 2001 , which covers the range of risks in the agriculture occupation, the prevention of these risks and

5390-553: The available work force, were employed in agriculture. This constitutes approximately 70% of the global employment of children, and in many countries constitutes the largest percentage of women of any industry. The service sector overtook the agricultural sector as the largest global employer in 2007. In many developed countries, immigrants help fill labor shortages in high-value agriculture activities that are difficult to mechanize. Foreign farm workers from mostly Eastern Europe, North Africa and South Asia constituted around one-third of

5500-597: The central west coast and eastern central, early farmers cultivated yams, native millet, and bush onions, possibly in permanent settlements. In the Middle Ages , compared to the Roman period , agriculture in Western Europe became more focused on self-sufficiency . The agricultural population under feudalism was typically organized into manors consisting of several hundred or more acres of land presided over by

5610-430: The concentrations of specific biological molecules (proteins, sugars, lipids, vitamins, fibers) and ease of processing (harvesting, milling, baking, malting, blending, etc.). Plant breeding can be performed using many different techniques, ranging from the selection of the most desirable plants for propagation, to methods that make use of knowledge of genetics and chromosomes, to more complex molecular techniques. Genes in

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5720-468: The cultivation of useful plants, and animal agriculture , the production of agricultural animals. The development of agriculture enabled the human population to grow many times larger than could be sustained by hunting and gathering . Agriculture began independently in different parts of the globe, and included a diverse range of taxa , in at least 11 separate centers of origin . Wild grains were collected and eaten from at least 105,000 years ago. In

5830-421: The desired traits. Furthermore, two different homozygous plants created in that way can be used to produce a generation of F1 hybrid plants which have the advantages of heterozygosity and a greater range of possible traits. Thus, an individual heterozygous plant chosen for its desirable characteristics can be converted into a heterozygous variety (F1 hybrid) without the necessity of vegetative reproduction but as

5940-668: The domestication of squash (Cucurbita) and other plants. Coca was domesticated in the Andes, as were the peanut, tomato, tobacco, and pineapple . Cotton was domesticated in Peru by 3,600 BC. Animals including llamas , alpacas , and guinea pigs were domesticated there. In North America , the indigenous people of the East domesticated crops such as sunflower , tobacco, squash and Chenopodium . Wild foods including wild rice and maple sugar were harvested. The domesticated strawberry

6050-443: The early 20th century, plant breeders realized that Gregor Mendel 's findings on the non-random nature of inheritance could be applied to seedling populations produced through deliberate pollinations to predict the frequencies of different types. Wheat hybrids were bred to increase the crop production of Italy during the so-called " Battle for Grain " (1925–1940). Heterosis was explained by George Harrison Shull . It describes

6160-432: The farm itself, entire families can be at risk for injuries, illness, and death. Ages 0–6 may be an especially vulnerable population in agriculture; common causes of fatal injuries among young farm workers include drowning, machinery and motor accidents, including with all-terrain vehicles. The International Labor Organization considers agriculture "one of the most hazardous of all economic sectors". It estimates that

6270-430: The forests of New Guinea have few food plants, early humans may have used "selective burning" to increase the productivity of the wild karuka fruit trees to support the hunter-gatherer way of life. The Gunditjmara and other groups developed eel farming and fish trapping systems from some 5,000 years ago. There is evidence of 'intensification' across the whole continent over that period. In two regions of Australia,

6380-419: The future include the lack of arable land, increasingly harsh cropping conditions and the need to maintain food security, which involves being able to provide the world population with sufficient nutrition. Crops need to be able to mature in multiple environments to allow worldwide access, which involves solving problems including drought tolerance. It has been suggested that global solutions are achievable through

6490-580: The general usability of the process across multiple target plant species. These methods will work even better with large, publicly available open data sets . Speed breeding is introduced by Watson et al. 2018. Classical (human performed) phenotyping during speed breeding is also possible, using a procedure developed by Richard et al. 2015. As of 2020 it is highly anticipated that SB and automated phenotyping will, combined, produce greatly improved outcomes – see § Phenotyping and artificial intelligence above. The NGS platform has substantially declined

6600-422: The greater use of pesticides and fertilizers. Multiple cropping , in which several crops are grown sequentially in one year, and intercropping , when several crops are grown at the same time, are other kinds of annual cropping systems known as polycultures . In subtropical and arid environments, the timing and extent of agriculture may be limited by rainfall, either not allowing multiple annual crops in

6710-515: The herbicide. This is the method used to produce glyphosate resistant (" Roundup Ready ") crop plants. Genetic modification can further increase yields by increasing stress tolerance to a given environment. Stresses such as temperature variation, are signalled to the plant via a cascade of signalling molecules which will activate a transcription factor to regulate gene expression . Overexpression of particular genes involved in cold acclimation has been shown to produce more resistance to freezing, which

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6820-493: The high-yield characteristics. Progeny from the cross would then be crossed with the high-yielding parent to ensure that the progeny were most like the high-yielding parent, ( backcrossing ). The progeny from that cross would then be tested for yield (selection, as described above) and mildew resistance and high-yielding resistant plants would be further developed. Plants may also be crossed with themselves to produce inbred varieties for breeding. Pollinators may be excluded through

6930-484: The high-yielding parent, the progeny will be crossed back to that parent for several generations (See backcrossing ). This process removes most of the genetic contribution of the mildew resistant parent. Classical breeding is therefore a cyclical process. With classical breeding techniques, the breeder does not know exactly what genes have been introduced to the new cultivars. Some scientists therefore argue that plants produced by classical breeding methods should undergo

7040-441: The input of nutrients (fertilizer or manure ) and some manual pest control . Annual cultivation is the next phase of intensity in which there is no fallow period. This requires even greater nutrient and pest control inputs. Further industrialization led to the use of monocultures , when one cultivar is planted on a large acreage. Because of the low biodiversity , nutrient use is uniform and pests tend to build up, necessitating

7150-548: The late 19th century. Gartons Agricultural Plant Breeders in England was established in the 1890s by John Garton, who was one of the first to commercialize new varieties of agricultural crops created through cross-pollination. The firm's first introduction was the Abundance Oat , an oat variety. It is one of the first agricultural grain varieties bred from a controlled cross, introduced to commerce in 1892. In

7260-476: The lower yield associated with organic farming and its impact on global food security . Recent mainstream technological developments include genetically modified food . By 2015, the agricultural output of China was the largest in the world, followed by the European Union, India and the United States. Economists measure the total factor productivity of agriculture, according to which agriculture in

7370-663: The marketplace are both safe and meet farmers' needs. Examples include variety registration, seed schemes, regulatory authorizations for GM plants, etc. Industrial breeding of plants has unintentionally altered how agricultural cultivars associate with their microbiome. In maize, for example, breeding has altered the nitrogen cycling taxa required to the rhizosphere, with more modern lines recruiting less nitrogen fixing taxa and more nitrifiers and denitrifiers . Microbiomes of breeding lines showed that hybrid plants share much of their bacterial community with their parents, such as Cucurbita seeds and apple shoot endophytes. In addition,

7480-466: The marketplace. Even with the very latest in biotech -assisted conventional breeding, incorporation of a trait takes an average of seven generations for clonally propagated crops, nine for self-fertilising , and seventeen for cross-pollinating . Modern plant breeding may use techniques of molecular biology to select, or in the case of genetic modification, to insert, desirable traits into plants. Application of biotechnology or molecular biology

7590-416: The need for breeding multiple generations of plants to get a generation that is homogeneous for the desired traits, thereby saving much time over the natural version of the same process. There are many plant tissue culturing techniques that can be used to achieve haploid plants, but microspore culturing is currently the most promising for producing the largest numbers of them. Genetic modification of plants

7700-821: The next generation than less-adapted individuals. Evolutionary plant breeding has been successfully used by the Nepal National Gene Bank to preserve landrace diversity within Jumli Marshi rice while reducing its susceptibility to blast disease. These practices have also been used in Nepal with bean landraces. In 1929, Harlan and Martini proposed a method of plant breeding with heterogeneous populations by pooling an equal number of F2 seeds obtained from 378 crosses among 28 geographically diverse barley cultivars. In 1938, Harlan and Martini demonstrated evolution by natural selection in mixed dynamic populations as

7810-437: The philosophy and culture of the farmer. Shifting cultivation (or slash and burn ) is a system in which forests are burnt, releasing nutrients to support cultivation of annual and then perennial crops for a period of several years. Then the plot is left fallow to regrow forest, and the farmer moves to a new plot, returning after many more years (10–20). This fallow period is shortened if population density grows, requiring

7920-454: The plant genome by genetic recombination using the bacteria Agrobacterium tumefaciens or A. rhizogenes , or by direct methods like the gene gun or microinjection . Using plant viruses to insert genetic constructs into plants is also a possibility, but the technique is limited by the host range of the virus. For example, Cauliflower mosaic virus (CaMV) only infects cauliflower and related species. Another limitation of viral vectors

8030-443: The plant. A marker for the selection of transformed plants is also included. In the laboratory , antibiotic resistance is a commonly used marker: Plants that have been successfully transformed will grow on media containing antibiotics; plants that have not been transformed will die. In some instances markers for selection are removed by backcrossing with the parent plant prior to commercial release. The construct can be inserted in

8140-414: The poorest countries, where alternative livelihoods are not available, and they maintain the intensity of their work in conditions of climate-induced weather shocks and in situations of conflict. Women are less likely to participate as entrepreneurs and independent farmers and are engaged in the production of less lucrative crops. The gender gap in land productivity between female- and male managed farms of

8250-577: The process of plant breeding, with its ability to select specific genes allowing crops to perform at a level which yields the desired results. One issue facing agriculture is the loss of landraces and other local varieties which have diversity that may have useful genes for climate adaptation in the future. Conventional breeding intentionally limits phenotype plasticity within genotypes and limits variability between genotypes. Uniformity does not allow crops to adapt to climate change and other biotic stresses and abiotic stresses . Plant breeders' rights

8360-440: The production of fish for human consumption in confined operations, is one of the fastest growing sectors of food production, growing at an average of 9% a year between 1975 and 2007. During the second half of the 20th century, producers using selective breeding focused on creating livestock breeds and crossbreeds that increased production, while mostly disregarding the need to preserve genetic diversity . This trend has led to

8470-595: The proportional contribution of the microbiome from parents to offspring corresponds to the amount of genetic material contributed by each parent during breeding and domestication. As of 2020 machine learning – and especially deep machine learning – has recently become more commonly used in phenotyping . Computer vision using ML has made great strides and is now being applied to leaf phenotyping and other phenotyping jobs typically performed by human eyes. Pound et al. 2017 and Singh et al. 2016 are especially salient examples of early successful application and demonstration of

8580-415: The quality required and evaluation of the target environment. A 2019 review of participatory plant breeding indicated that it had not gained widespread acceptance despite its record of successfully developing varieties with improved diversity and nutritional quality, as well as greater likelihood of these improved varieties being adopted by farmers. This review also found participatory plant breeding to have

8690-477: The result of conflict, climate extremes and variability and economic swings. It can also be caused by a country's structural characteristics such as income status and natural resource endowments as well as its political economy. Pesticide use in agriculture went up 62% between 2000 and 2021, with the Americas accounting for half the use in 2021. The International Fund for Agricultural Development posits that an increase in smallholder agriculture may be part of

8800-435: The result of the cross of two homozygous/doubled haploid lines derived from the originally selected plant. This shortcut has been dubbed 'reverse breeding'. Plant tissue culturing can produce haploid or double haploid plant lines and generations. This cuts down the genetic diversity taken from that plant species in order to select for desirable traits that will increase the fitness of the individuals. Using this method decreases

8910-874: The role that individuals and organizations engaged in agriculture should play. In the United States, agriculture has been identified by the National Institute for Occupational Safety and Health as a priority industry sector in the National Occupational Research Agenda to identify and provide intervention strategies for occupational health and safety issues. In the European Union, the European Agency for Safety and Health at Work has issued guidelines on implementing health and safety directives in agriculture, livestock farming, horticulture, and forestry. The Agricultural Safety and Health Council of America (ASHCA) also holds

9020-478: The salaried agricultural workforce in Spain, Italy, Greece and Portugal in 2013. In the United States of America, more than half of all hired farmworkers (roughly 450,000 workers) were immigrants in 2019, although the number of new immigrants arriving in the country to work in agriculture has fallen by 75 percent in recent years and rising wages indicate this has led to a major labor shortage on U.S. farms. Around

9130-405: The same safety testing regime as genetically modified plants. There have been instances where plants bred using classical techniques have been unsuitable for human consumption, for example the poison solanine was unintentionally increased to unacceptable levels in certain varieties of potato through plant breeding. New potato varieties are often screened for solanine levels before reaching

9240-439: The same size is 24 percent. On average, women earn 18.4 percent less than men in wage employment in agriculture; this means that women receive 82 cents for every dollar earned by men. Progress has been slow in closing gaps in women's access to irrigation and in ownership of livestock, too. Women in agriculture still have significantly less access than men to inputs, including improved seeds, fertilizers and mechanized equipment. On

9350-434: The same. If a gene's location and function is identified in one plant species, a very similar gene likely can also be found in a similar location in another related species genome. Homozygous plants with desirable traits can be produced from heterozygous starting plants, if a haploid cell with the alleles for those traits can be produced, and then used to make a doubled haploid . The doubled haploid will be homozygous for

9460-568: The short time that elapsed between the Inca conquest (c. 1470) and the arrival of the Spanish (1532) they were not completely assimilated into the empire. Narihualá (17 km south of Piura ) is considered the capital of the Tallán Nation and is the most important architectural evidence of a great monument, both in its size and the prominent platforms of two pyramids. The Narihualá Temple

9570-488: The solution to concerns about food prices and overall food security , given the favorable experience of Vietnam. Agriculture provides about one-quarter of all global employment, more than half in sub-Saharan Africa and almost 60 percent in low-income countries. As countries develop, other jobs have historically pulled workers away from agriculture, and labor-saving innovations increase agricultural productivity by reducing labor requirements per unit of output. Over time,

9680-561: The south of France , are now grown in southern Germany. Plant breeding started with sedentary agriculture and particularly the domestication of the first agricultural plants, a practice which is estimated to date back 9,000 to 11,000 years. Initially early farmers simply selected food plants with particular desirable characteristics, and employed these as progenitors for subsequent generations, resulting in an accumulation of valuable traits over time. Grafting technology had been practiced in China before 2000 BCE. By 500 BCE grafting

9790-400: The synthesis of ammonium nitrate fertilizer on an industrial scale, greatly increasing crop yields and sustaining a further increase in global population. Modern agriculture has raised or encountered ecological, political, and economic issues including water pollution , biofuels , genetically modified organisms , tariffs and farm subsidies , leading to alternative approaches such as

9900-570: The tendency of the progeny of a specific cross to outperform both parents. The detection of the usefulness of heterosis for plant breeding has led to the development of inbred lines that reveal a heterotic yield advantage when they are crossed. Maize was the first species where heterosis was widely used to produce hybrids. Statistical methods were also developed to analyze gene action and distinguish heritable variation from variation caused by environment. In 1933 another important breeding technique, cytoplasmic male sterility (CMS), developed in maize,

10010-590: The term evolutionary plant breeding and concluded that 15 generations of natural selection are desirable to produce results that are competitive with conventional breeding. Evolutionary breeding allows working with much larger plant population sizes than conventional breeding. It has also been used in tandem with conventional practices in order to develop both heterogeneous and homogeneous crop lines for low input agricultural systems that have unpredictable stress conditions. Evolutionary plant breeding has been delineated into four stages: Issues facing plant breeding in

10120-478: The time and cost required for sequencing and facilitated SNP discovery in model and non-model plants. This in turn has led to employing large-scale SNP markers in genomic selection approaches which aim at predicting genomic breeding values/GEBVs of genotypes in a given population. This method can increase the selection accuracy and decrease the time of each breeding cycle. It has been used in different crops such as maize, wheat, etc. Participatory plant breeding (PPB)

10230-679: The transition from hunter-gatherer to agricultural societies indicate an initial period of intensification and increasing sedentism ; examples are the Natufian culture in the Levant , and the Early Chinese Neolithic in China. Then, wild stands that had previously been harvested started to be planted, and gradually came to be domesticated. In Eurasia, the Sumerians started to live in villages from about 8,000 BC, relying on

10340-529: The use of pollination bags . Classical breeding relies largely on homologous recombination between chromosomes to generate genetic diversity . The classical plant breeder may also make use of a number of in vitro techniques such as protoplast fusion , embryo rescue or mutagenesis (see below) to generate diversity and produce hybrid plants that would not exist in nature . Traits that breeders have tried to incorporate into crop plants include: Successful commercial plant breeding concerns were founded from

10450-405: The visual identification of the expressed trait in the plant. The purpose of marker assisted selection, or plant genome analysis, is to identify the location and function ( phenotype ) of various genes within the genome. If all of the genes are identified it leads to genome sequence . All plants have varying sizes and lengths of genomes with genes that code for different proteins, but many are also

10560-671: The wild aurochs in the areas of modern Turkey and Pakistan some 10,500 years ago. Pig production emerged in Eurasia, including Europe, East Asia and Southwest Asia, where wild boar were first domesticated about 10,500 years ago. In the Andes of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, coca , llamas , alpacas , and guinea pigs . Sugarcane and some root vegetables were domesticated in New Guinea around 9,000 years ago. Sorghum

10670-744: The world consist of fewer than 2 hectares (4.9 acres), and take up only around 12% of all agricultural land. Farms and farming greatly influence rural economics and greatly shape rural society , affecting both the direct agricultural workforce and broader businesses that support the farms and farming populations. The major agricultural products can be broadly grouped into foods , fibers , fuels , and raw materials (such as rubber ). Food classes include cereals ( grains ), vegetables , fruits , cooking oils , meat , milk , eggs , and fungi . Global agricultural production amounts to approximately 11 billion tonnes of food, 32 million tonnes of natural fibers and 4 billion m of wood. However, around 14% of

10780-781: The world's agricultural land is seriously degraded. In recent years there has been a backlash against the environmental effects of conventional agriculture, resulting in the organic , regenerative , and sustainable agriculture movements. One of the major forces behind this movement has been the European Union , which first certified organic food in 1991 and began reform of its Common Agricultural Policy (CAP) in 2005 to phase out commodity-linked farm subsidies, also known as decoupling . The growth of organic farming has renewed research in alternative technologies such as integrated pest management , selective breeding, and controlled-environment agriculture . There are concerns about

10890-664: The world's food is lost from production before reaching the retail level. Modern agronomy , plant breeding , agrochemicals such as pesticides and fertilizers , and technological developments have sharply increased crop yields , but also contributed to ecological and environmental damage . Selective breeding and modern practices in animal husbandry have similarly increased the output of meat, but have raised concerns about animal welfare and environmental damage. Environmental issues include contributions to climate change , depletion of aquifers , deforestation , antibiotic resistance , and other agricultural pollution . Agriculture

11000-485: The world, women make up a large share of the population employed in agriculture. This share is growing in all developing regions except East and Southeast Asia where women already make up about 50 percent of the agricultural workforce. Women make up 47 percent of the agricultural workforce in sub-Saharan Africa, a rate that has not changed significantly in the past few decades. However, the Food and Agriculture Organization of

11110-495: The world. In the 20th century, industrial agriculture based on large-scale monocultures came to dominate agricultural output. As of 2021 , small farms produce about one-third of the world's food, but large farms are prevalent. The largest 1% of farms in the world are greater than 50 hectares (120 acres) and operate more than 70% of the world's farmland. Nearly 40% of agricultural land is found on farms larger than 1,000 hectares (2,500 acres). However, five of every six farms in

11220-621: The world. Production is listed in millions of metric tons, based on FAO estimates. Animal husbandry is the breeding and raising of animals for meat, milk, eggs , or wool , and for work and transport. Working animals , including horses, mules , oxen , water buffalo , camels, llamas, alpacas, donkeys, and dogs, have for centuries been used to help cultivate fields, harvest crops, wrangle other animals, and transport farm products to buyers. Livestock production systems can be defined based on feed source, as grassland-based, mixed, and landless. As of 2010 , 30% of Earth's ice- and water-free area

11330-444: Was a key factor in the rise of sedentary human civilization , whereby farming of domesticated species created food surpluses that enabled people to live in the cities. While humans started gathering grains at least 105,000 years ago, nascent farmers only began planting them around 11,500 years ago. Sheep, goats, pigs, and cattle were domesticated around 10,000 years ago. Plants were independently cultivated in at least 11 regions of

11440-754: Was built as a sanctuary in the honour of the Tacllán god Walac . Huaca El Loro , near Chiclayo, Peru is a Tallán archaeological site, where a 1000-year-old mummy of a nobleman was discovered. This article relating to archaeology in Peru is a stub . You can help Misplaced Pages by expanding it . This article related to an ethnic group in South America is a stub . You can help Misplaced Pages by expanding it . Agriculture Agriculture encompasses crop and livestock production, aquaculture , and forestry for food and non-food products. Agriculture

11550-474: Was described by Marcus Morton Rhoades . CMS is a maternally inherited trait that makes the plant produce sterile pollen . This enables the production of hybrids without the need for labor-intensive detasseling . These early breeding techniques resulted in large yield increase in the United States in the early 20th century. Similar yield increases were not produced elsewhere until after World War II ,

11660-640: Was domesticated by the Mayo Chinchipe of the upper Amazon around 3,000 BC. The turkey was probably domesticated in Mexico or the American Southwest. The Aztecs developed irrigation systems, formed terraced hillsides, fertilized their soil, and developed chinampas or artificial islands. The Mayas used extensive canal and raised field systems to farm swampland from 400 BC. In South America agriculture may have begun about 9000 BC with

11770-560: Was domesticated in the Sahel region of Africa by 7,000 years ago. Cotton was domesticated in Peru by 5,600 years ago, and was independently domesticated in Eurasia. In Mesoamerica , wild teosinte was bred into maize (corn) from 10,000 to 6,000 years ago. The horse was domesticated in the Eurasian Steppes around 3500 BC. Scholars have offered multiple hypotheses to explain the historical origins of agriculture. Studies of

11880-584: Was used for producing livestock, with the sector employing approximately 1.3 billion people. Between the 1960s and the 2000s, there was a significant increase in livestock production, both by numbers and by carcass weight, especially among beef, pigs and chickens, the latter of which had production increased by almost a factor of 10. Non-meat animals, such as milk cows and egg-producing chickens, also showed significant production increases. Global cattle, sheep and goat populations are expected to continue to increase sharply through 2050. Aquaculture or fish farming,

11990-441: Was used to double the number of chromosomes in the cell and thus allow the production of a fertile line. Failure to produce a hybrid may be due to pre- or post- fertilization incompatibility. If fertilization is possible between two species or genera, the hybrid embryo may abort before maturation. If this does occur the embryo resulting from an interspecific or intergeneric cross can sometimes be rescued and cultured to produce

12100-437: Was well established and practiced. Gregor Mendel (1822–84) is considered the "father of genetics ". His experiments with plant hybridization led to his establishing laws of inheritance . Genetics stimulated research to improve crop production through plant breeding. Selective breeding played a crucial role in the Green Revolution of the 20th century. Modern plant breeding is applied genetics, but its scientific basis

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