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Features that breeders have tried to incorporate into plant species include the following. Improved quality, such as increased nutrition, improved taste, or greater beauty Give the crop an enlarged path increased tolerance environmental pressure (salinity, extreme temperature, drought) Resistance to viruses, fungi and bacteria Increase tolerance to insect pests Tolerance herbicides the shelf life of the harvested crop is longer
before World War Garton's 1902 catalogSuccessful commercial plant care concerts have been around since the late 19th century. .commercialized new varieties of agricultural crops created by pollination. The firm's first presentation was the Abundance Cross, one of the first agricultural grain varieties grown from oats, introduced in 1892.
In the early 20th century, plant breeders realized that Mendel's findings on non-random nature could be used to inherit intentionally generated populations of seedlings to predict frequencies of different types of pollination
In the early 20th century, plant breeders realized that Mendel's findings on non-random nature could be used to inherit intentionally generated populations of seedlings to predict frequencies of different types of pollination. The hybrids of wheat were grown to increase yields in Italy during the so-called "Battle for Don" (1925–1940). Heterosis was explained by George Harrison Shull. This describes the tendency of a particular cross generation to be superior to both parents. determining the usefulness of heterosis for plant propagation has led to the development of breeding lines that show the predominance of heterotic yields in crossing them. Corn was the first species to make extensive use of heterosis to produce hybrids. statistical methods have also been developed to analyze the effects of genes and to distinguish genetic changes from those caused by the environment. In 1933, another important breeding technique, cytoplasmic male sterility (CMS), was produced in corn, bydescribed Marcus Morton Rhoades.cMS is a trait inherited from the mother that leads to the sterile formation of the plant. This allows the production of hybrids without much labor detasseling. As a result of these early breeding techniques led to a huge increase in yield in the United States in the early 20th century. similar productivity growth was not produced elsewhere later in World War II, when the Green Revolution increased crop production in the developing world in the 1960s.
agricultural research on potato crops
When the desired trait is converted to a species, several crosses are made to the optimal parent to make the new plant as similar to the preferred parent as possible. going back to the example where the mold-resistant pea is crossed with a high-yielding but sensitive pea, the offspring is returned to the parent for several generations to make the cross-resistant pea resemble a high-yielding parent (see go back). this process removes the genetic contribution of the mold-resistant parent. Classical breeding is therefore a cyclical process.
With the classical breeding technique, the breeder does not know exactly what genes were introduced into the new varieties. some scientists therefore genetically modified plants that need to be switched to safety testing mode for plants produced by classical breeding methods. There have been cases where plants grown using classical methods have become unfit for human consumption, for example the poison has risen to unacceptable levels in some varieties of solanine by propagating potato plants. new varieties of potatoes are often tested for solanine content before reaching the market.
Growing modern plants
modern plant cultivation can use molecular biology methods in selection or genetic modification to add desired properties to plants. Application of biotechnology or molecular biology, as well as known molecular breeding.
modern constructions in molecular biology are now used in plant propagation.

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Marker helped with the selection
Main article: Marker helped with the selection
sometimes different genes can influence a desired trait in plant cultivation. Using tools such as molecular markers or DNA fingerprints can map thousands of genes. this allows plant breeders to select large populations of plants for those with an interest trait. .screening is based not on the visual identification of an expressed trait in a plant, but on the presence or absence of a specific gene identified by laboratory procedures. The purpose of selection or analysis of a plant genome using a marker is to determine the location and function (phenotype) of different genes within the genome. if all genes are identified, the cause is a genome sequence. [quote] [should be explained] All plants have different genomes and lengths with genes encoding different proteins, but many are the same. if the location and function of a gene in one plant species are determined, it is likely that a very similar gene can be found in a similar location in the genome of another genome. [11]
Reverse breeding and doubling haploids (DH)
Main article: Twice haploidy
[should be explained] Homozygous plants with the desired properties can be produced heterozygous primary plants, if for these properties an allelic haploid cell is formed, and then doubled haploid. the doubled haploid is homogeneous for the desired characteristics.moreover, F1 hybrid heterozygosity, which can be used to create offspring from two different homozygous plants created in this way, is a plant with a wide range of advantages and possible characteristics. thus, an individual heterozygous plant selected according to its desired characteristics can become a heterozygous variety (F1 hybrid). vegetative reproduction but as a result of a cross of two homozygous / twice as many haploid lines derived from the originally selected plant. [12] When cultivating plant tissue, haploid or double haploid plant lines and offspring may appear. This reduces the genetic diversity derived from these plant species to select the desired traits that increase the physical fitness of individuals. the use of this method reduces the need to cultivate
several generations of plants to obtain a homogeneous generation for the desired characteristics, and thus saves a great deal of time in the natural version of the same process. there are many plant tissue cultivation techniques that can be used to grow haploid plants, but microspore cultivation is currently the most promising to produce the largest number of them.
Genetic modification
main article: Transgenic plants
Genetic modification is achieved by adding a specific gene or genes to a plant or by knocking out a gene RNAi, a phenotype that produces what is needed. Plants formed as a result of gene addition are often called transgenic plants. If the genes of a species or plant to be genetically modified are used under the control of a local promoter, then they are called sisgen plants. sometimes genetic modification can result in the emergence of a plant that has the desired trait or characteristics rather than the classical lineage, as most of the plant genome has not changed.
a genetic construct must be designed to genetically modify a plant so that the gene to be added or removed is expressed by the plant. for this, a termination sequence and a gene or genes of interest must be introduced into the plant to stop a propagator driving transcription and the transcription of a new gene. A marker is also included to select altered plants. in the laboratory, antibiotic resistance is a commonly used marker: Successfully transformed plants grow in an environment containing antibiotics; unaltered plants die. In some cases the markers for selection are deleted by the parent factory before the commercial release.
the use of genetically recombination bacteria that can be incorporated into the plant genome Agrobacterium tumefaciens or A. rhizogenlari or gene weapon or microinjection by direct methods. plant use viruses can also introduce genetic constructs into plants, but this method is limited to the main scope of the virus. For example, cauliflower mosaic virus (CaMV) infects only cauliflower and related species. another limitation of viral vectors is that the virus usually does not pass on to offspring, so every plant needs to be vaccinated.
Most of the commercially available transgenic plants are currently limited to plants that are resistant to insect pests and herbicides. The insect resistance gene is achieved by attaching a gene (Bt) protein encoding Bacillus thuringiensis A that is toxic to some insects. For example, cotton worm, a common cotton pest, feeds on Bt cotton it swallows the toxin and dies. herbicides usually work by binding to certain plant enzymes and inhibiting their effects. [13] Enzymes that inhibit herbicides are called herbicides target site. A protein that is not inhibited by the target site herbicide can be introduced into crops by expressing a version of herbicide resistance. This is the method used to produce glyphosate-resistant (“Ready to Assemble”) herbaceous plants.
genetic modification can further increase yields by increasing tolerance to a particular environment. Stresses such as temperature changes signal the plant through cascades of signaling molecules and they activate the transcription factor regulating gene expression. overproduction of certain genes involved in cold climates has been shown to be more resistant to freezing, which is one of the common causes of loss of productivity [14].
Genetic modification of plants that can produce pharmaceuticals (and industrial chemicals), sometimes called pharmacies, is a radically new direction in plant cultivation. [15]
Problems and concerns
the cultivation of modern plants through classical or genetic engineering is associated with problems, especially those related to food crops. The question of whether breeding can have a negative impact on nutritional value is central in this regard. although relatively little direct research has been done in this area, there are scientific indications that other aspects may be left behind by approving certain aspects of plant development. The study, published in the Journal of the American College of Nutrition in 2004, compared the nutritional analysis of USDA food composition data for 43 horticultural crops from 1950 to 1999. andSignificant reductions were found in six of the measured nutrients, including 6% protein and 38% riboflavin. The reduction was found in calcium, phosphorus, iron and ascorbic acid.a study by the Institute of Biochemistry, University of Texas at Austin, summarizes: l.give and nutrient content."[16]In the 1990s
the debate over genetically modified food peaked in 1999 in terms of media coverage and risk perception, [17] and continues to this day - for example, “Germany is gaining weight. In Europeby banning the planting of a genetically modified crop of resistant pest-resistant maize, which was thrown behind the uprising. "[18] The discussion includes the environmental impact of genetically modified plants, the significant equivalence of the concepts used to assess the safety of genetically modified foods and the like. such concerns are not new to plant reproduction. In many countries, there are regulatory processes that help ensure that new crop varieties entering the market are safe and meet the needs of farmers. this includes varietal registration, seed schemes, normative permits for GM plants, and more.
The rights of plant breeders are also a big and controversial issue. today, in the production of new varieties, commercial plant breeders dominate, collecting on the basis of national and international agreements based on the protection of their work and the collection of royalties. intellectual property rights. The scope of issues is complex.in simple terms, critics of increasingly restrictive rules argue that commercial breeders are declining through a combination of technical and economic pressures. biodiversity and seed production at the regional level (e.g., farmers) andsignificantly restricting those involved in sales. [19] For example, work is underway to strengthen the rights of breeders by extending the protection period of varieties. [Quote]
When new plant breeds or varieties are propagated, they need to be cared for and propagated. some plants reproduce asexually, while others reproduce by seeds. Propagated seed varieties require precise control over seed source and production procedures to maintain the integrity of plant seed results. isolation is necessary to prevent cross-contamination with appropriate plants or mixing of seeds after harvest. insulation is usually done at planting distance, but in some crops the plants are covered in greenhouses or cages (often used in the production of F1 hybrids).
The role of plant cultivation in organic agriculture
critics say organic farming has a very low yield to be an alternative to this traditional agriculture. However, part of this poor performance may be the result of cultivating poorly adapted varieties. [20] [21] More than 95% of organic agriculture is considered to be based on traditionally adapted varieties, although the production environment available in organic and traditional farming systems is very poor due to their specific management methods. is different. [21] It is noteworthy that organic farmers have less information than conventional producers to control their production environments. breeding varieties adapted to the specific conditions of organic agriculture are very important for the industry to fully realize its potential. To do this, select the following features: [21]
Water use efficiency
nutrient utilization efficiency (especially nitrogen and phosphorus)
Competitiveness of weeds
Tolerance mechanical weeding
Resistance to pests / diseases
Early maturity (as a mechanism to avoid certain stresses)
resistance to abiotic stress (i.e. drought, salinity, etc. ...)at present, few breeding programs are focused on organic agriculture, and until recently, those who tackled this field have generally relied on indirect selection (i.e., traits that are considered important for organic farming in a traditional environment). however, because the difference between an organic and a conventional environment is large, a given genotype can work very differently in each environment due to the interaction between genes and the environment (see) siri). if this interaction is severe enough, an important feature required for an organic environment in a traditional environment may not be identified, which may lead to the selection of poorly adapted individuals. [20] To ensure the identification of the most suitable varieties, proponents of organic breeding are now advocating the use of direct selection (i.e., selection in the target environment) for many agrotechnical characteristics.
genetically modified organisms that have many classical and modern breeding techniques that can be used to improve yields, despite being banned in organic agriculture. for example, controlled crosses between individuals allow the desired genetic modification to be combined and passed on to the offspring through natural processes. The marker helped in the selection and can also be used as a diagnostic tool to facilitate the selection of the breed with the desired feature (s) and to significantly speed up the breeding
process. This method has proven to be very useful, especially for the entry of resistance genes into new backgrounds and for the effective selection of multiple resistance genes pyramidated into a single individual. unfortunately, molecular markers are currently not available for many important traits, especially for complex properties controlled by many genes.
Breeding and food safety
for future agricultural development, changes need to be made to address emerging global challenges. these issues include the lack of arable land, increasingly difficult planting conditions, and the need to ensure food security, which includes the ability to provide adequate nutrition to the world’s population. crops need to ripen in multiple environments to allow access to the whole world, which includes drought tolerance, including problem solving. global solutions can be achieved in the process of plant propagation, which has the ability to select specific genes that allow crops to function to the extent that they produce the desired results.
Give Way
as the population grows, food production should increase with it. It is estimated that by 2050, food production will need to increase by 70 per cent to meet the declaration of the World Summit on Food Security. but with the degradation of agricultural lands, simply planting more crops is no longer a viable option. New varieties of plants can in some cases be created by propagating plants that increase yields without believing in an increase in land area. An example of this can be seen in Asia, where per capita food production has doubled. This was achieved not only through the use of fertilizers, but also through the use of better crops specifically designed for the area.
Nutritional value
plant cultivation can contribute to global food security as it is a cost-effective tool to increase the nutritional value of nutrients and crops. improvements in nutritional value for fodder crops using analytical chemistry and rum fermentation technology have been noted since the 1960s; this science and technology has allowed breeders to sort thousands of specimens in a short period of time, i.e. breederscould identify a high-quality hybrid faster.genetic improvement was mainly in vitro dry matter digestibility (IVDMD) resulting in an increase of 0.7–2.5%, while IVDMD increased by only 1%, a single Bos Taurus, as well as meaty daily income, known as cattle, increased by 3.2%. this improvement indicates that plant cultivation is an important tool in the future at a higher level of agricultural performance.
Factors affecting the environment
plant cultivation of hybrid crops has become extremely popular all over the world in order to combat harsh environments. long-term drought and water scarcity or nitrogen resistance have become an important part of agriculture. One way to achieve this is to reduce itfinding crop strains resistant to nitrogen drought conditions.it is clear that plant cultivation is critical to maintaining agriculture in the future as it allows farmers to grow stress-resistant crops and thereby improve food security. In countries that have experienced severe winters, such as Iceland, Germany, and eastern Europe, plant breeders breed for cold tolerance, constant snow cover, cold-drought (drying from wind and sunlight under cold), and high humidityare engaged. in the soil in winter.
Propagation of plants by participation
Plant Breeding (PPB) is the participation of farmers in a crop improvement program that enables them to make decisions at different stages and contribute to the research process. When plant biotechnologies are used to improve crops, joint approaches to crop improvement can also be applied. Local agricultural systems and genetic diversity are developed and strengthened through crop improvement, which plays a major role in co-crop improvement (PCI). pPB farmers improve their knowledge of the target environment required to influence the quality and effectiveness of PPB.
List of well-known plant breeders
Thomas Andrew Knight
Keith Downey
Luther Burbank
Nazareno Strampelli
Nilz Ebbesen Xansen
Nerman Borlaug
See also
Bioactive accumulation
Sisgenez
Growing plants in Nepal
Taxonomy of cultivated plants
Two pairs of pairs
EUCARPIA
Family QTL map
The genomics of home-making
International Nomenclature Code for Cultivated Plants
Marker selection (MAS)
orthodox seed
QTL map
Naked Seed
Selection methods in the selection of plants based on the method of reproduction
Intelligent breeding
Composite cross population
Bioprospecting / biopiracy / Access and Distribution Agreement
plant agreement / Convention on Biological Diversity and Nagoya Protocol
UPOV Convention on New Varieties of Plants
Farmers 'Rights / Farmers' Rights
Genetic resources (separation)
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