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SELECTIVE BREEDING VS GENETICALLY MODIFIED FOODS BY: MR. NIEMIECKI SELECTIVE BREEDING Selective breeding is the process of breeding plants and animals for particular genetic traits. Typically the strains which are selectively bred are domesticated, and done by a professional breeder. Bred animals are known as breeds, while bred plants are known as varieties. PURE BREEDS Animals with the same appearance, behaviour, and other characteristics are known as particular breeds bred through culling particular traits and selecting for others. Purebred animals have a single, recognizable breed CROSS BREEDS The cross of animals results in what is called a crossbreed and crossbred plants are called hybrids. Crossbreeds are a mix of two purebreds, while mixed breeds are a mix of several breeds Involves culling and selection for "superior" qualities to develop a breed superior in certain respects to the original. ANIMAL BREEDING Breeders look for valuable traits in purebred animals for a certain purpose Crossbreed to produce a new type of animal with different, and probably superior traits E.g. To breed chickens, a typical breeder wants the most eggs and meat from chickens The breeder analyses the breeds of chickens to understand what traits can be expected from breeding a 2 chickens "breeding the best to the best” PLANT BREEDING Researchers at the USDA have selectively bred carrots with a variety of colours. Plant breeding has been used for thousands of years Began with the domestication of wild plants into predictable breeds Such as high-yielding varieties or fruit trees have been particularly important in agriculture. PLANT CROSS BREEDING Crossbreeding crops to produce new crop varieties with desirable properties. To introduce traits/genes from other plants to bred a new plant E.g. A fungus-resistant pea may be crossed with a highyielding pea, the goal of the cross being to introduce fungus resistance without losing the high-yield characteristics. The process isnt 100% and involves a lot of trial and error DESIRBALE TRAITS FOR PLANTS Traits that breeders have tried to incorporate into crop plants and animals in the last 100 years include: Increased quality and yield of the crop Increased tolerance of environmental pressures (salinity, extreme temperature, drought) Resistance to viruses, fungi and bacteria Increased tolerance to insect pests SOME PROBLEMS With selective breeding techniques, the breeder does not know exactly what genes have been introduced to the new breeds of plants or animals Some scientists therefore argue that plants produced by classical breeding methods should undergo the same safety testing regime as genetically modified plants. There have been instances where plants bred 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. (GM) GENETICALLY MODIFIED Genetic modification of plants/ animals by adding a specific gene or by knocking out a gene to produce a desirable phenotype. To produce a transgenic plants or animals Genetic modification can produce a plant with the desired trait or traits faster than selective breeding because the majority of the plant's genome is not altered. GM USES Transgenic plants are currently have introduced resistance to insect pests and herbicides. Genetic modification of plants/ animals that can produce industrial chemicals, vaccines for diseases, medicines and cure world hunger!! Add genes from other animal kingdoms which cant be done with selective breeding Eg. - The tall rooster (giraffe genes) - Dog with genes from a cheetah - Bananas with HIV vaccines - Strawberries that have bacteria genes to survive the cold ISSUES AND CONCERNS Breeding can have a negative effect on nutritional value Compared nutrition of vegetables done in 1950 and in 1999 found decreases in six of 13 nutrients measured, including 6% of protein and reductions in calcium, phosphorus and iron The ecological impact of genetically modified organisms, the safety of genetically modified food and concepts used for safety evaluation Plant breeders' rights as production of new varieties is dominated by commercial plant breeders, who seek to protect their work and collect money through intellectual property rights. Efforts to strengthen breeders' rights Isolation is necessary to prevent cross contamination with related plants or the mixing of seeds after harvesting. Isolation is normally accomplished by planting distance but in certain crops, plants are enclosed in greenhouses or cages