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Genetic Modification Technology GM technology was first developed in the 1970s. One of the most prominent developments, apart from the medical applications, has been the dev elopment of ovel transgenic crop plant varieties including soybean, cotton, tobacco, potato and maize Genetic Need for GM technology in Agncul By 2030, the world population will increase from todays 6 billion to 8 billion. Today there ar 800 million people(18% of the population in the developing world) who do not have access to sufficient food to meet their needs due to Need for GM technology in Agriculture Lack of food ed for GM technology in Agriculture Global climate change and alterations in the use of land will exacerbate the problem of regional production and demands for food. Increasing the amount of land to cultivate crops without having a serious impact on the environment and natural resources is a limited option(c f. marginal lands) Need for GM technology in Agrculture developing countries, about 650 million ofthe poorest people live in rural areas where the local production of food is their main activity he three most important elements in rural community are increase in crop yield income generation and more effective distr bution of food stocks. GM Need for GM technology in Agriculture High input agriculture involves large-scale use of pesticides and fertilizers that are expensive and can potentially affect human health or damage the ecosystem What is Transgenic Agriculture Transgenic agriculture aims selectively to alter, add or remove a characteristic of choice in a plant It brings in not only desirable characteristics fiom other varieties of the plant, but also adds characteristics from other unrelated species. Thereafter the transgenic plant becomes a parent for use in traditional breeding Properties of GM Foods Correct micro-nutrient deficiencies reduces expenses and resources required to implement supplementation programs pest, herbicide, and viral, bacterial and fungal disease of GM Foods on of plant architecture(e.g. height) and development (e.g. early or late flowering), tolerance to stresses (e.g. salinity and drought, production of ndustrial chemicals, use of biomass for fuel; flexibility in crop management, enhanced yields, easier harvesting and higher proportions of the crop for trading Stable and increased length of storage due to delayed ripening or softening Pest Transgenic crops(e.g. cotton, papaya) containing insect-resistance ge om Bacillus thuringiensis reduces significantly the amount of insecticide application In the USA, there was a reduction of 2 million hectare treatments of about I million kilograms of chemical insecticides in 1999 compared to 1998(US National st resistance gene transfer is, however, pest-, region- and cultivar-specific Resistance of pest to the transgenic crop can still happe Examples of GM Technology Crop yield can be increased by modifying growth patten of the plant parts Typical example is the high-yielding semi-dwarf wheat with the added "Japanese NORIN 10 genes Two benefits of these dwarfing genes o more fertilizer without collapsing crease yield directly by reducing cell elongation in the plant vegetative plant parts, thereby allowing the plant to invest more in the reproductive plant parts These genes can be used to transform other crop species(Peng et al. 1999) erance to Biotic Abiotic stresses Most of the examples are concemed with viruses, bacteria selected soil limiting factors Tolerance to Biotic Abiotic Stresses These sources of resistance need to be more stable than the traditional intra-species sources Examples of GM Technology Marginal lands suffer from different problems including salinity and alkalinity ples of GM Technology itamin A deficiency causes half a million children to become partially or totally blind each year( Conway 999). Researchers introduced 3 genes into rice(2 from daffodils and 1 from a bacterium called Erw exhibit tamin a and the seed is yellow in color hence know as golden rice (Ye et al. 2000). See also the February issue of TImE magazine Examples of GM Technology Examples of GM Technology en. About 400 million child-bearing age suffer and give birth to underweight hildren and to mortality at childbirth. Anemia contributes to over 20% of matemal deaths (after giving birth) in Asia and Africa(Conway 1999). Transgenic facilitates iron availability in the human diet( Goto et al. 1999) educed Environmenta GM technology is a useful tool for the introduction of root disease resistance for conditions of reduced tillage. This will help reduce soil erosion pharmaceuticals vaccines fiom T M technology has the potential of pi 1995)4 Genetic Modification Technology Genetic Engineering GM technology was first developed in the 1970s. One of the most prominent developments, apart from the medical applications, has been the development of novel transgenic crop plant varieties including soybean, cotton, tobacco, potato and maize Genetic Engineering Need for GM technology in Agriculture By 2030, the world population will increase from today’s 6 billion to 8 billion. Today there are some 800 million people (18% of the population in the developing world) who do not have access to sufficient food to meet their needs due to poverty and unemployment. Need for GM technology in Agriculture Each year nearly 12 million children under 5 in developing countries die because of Malnutrition Lack of food Deficiencies in micro-nutrients (vitamin A, iodine and iron) Need for GM technology in Agriculture Global climate change and alterations in the use of land will exacerbate the problem of regional production and demands for food. Increasing the amount of land to cultivate crops without having a serious impact on the environment and natural resources is a limited option (c.f. marginal lands) Need for GM technology in Agriculture In developing countries, about 650 million of the poorest people live in rural areas where the local production of food is their main activity The three most important elements in rural community are: increase in crop yield, income generation and more effective distri bution of food stocks.GM technology are relevant to these elements of food security Need for GM technology in Agriculture High input agriculture involves large-scale use of pesticides and fertilizers that are expensive and can potentially affect human health or damage the ecosystem What is Transgenic Agriculture? Transgenic agriculture aims selectively to alter, add or remove a characteristic of choice in a plant, bearing in mind regional needs and opportunities It brings in not only desirable characteristics from other varieties of the plant, but also adds characteristics from other unrelated species. Thereafter the transgenic plant becomes a parent for use in traditional breeding Properties of GM Foods More nutritious – improves human health addressing malnutrition and under-nutrition Correct micro-nutrient deficiencies – reduces expenses and resources required to implement supplementation programs Resistant to pest, herbicide, and viral, bacterial and fungal disease Properties of GM Foods Modification of plant architecture (e.g. height) and development (e.g. early or late flowering); tolerance to stresses (e.g. salinity and drought); production of industrial chemicals; use of biomass for fuel; flexibility in crop management, enhanced yields, easier harvesting and higher proportions of the crop for trading etc Stable and increased length of storage due to delayed ripening or softening Examples of GM Technology Pest resistance Transgenic crops (e.g. cotton, papaya) containing insect-resistance genes from Bacillus thuringiensis reduces significantly the amount of insecticide application. In the USA, there was a reduction of 2 million hectare-treatments of about 1 million kilograms of chemical insecticides in 1999 compared to 1998 (US National Research Council 2000) Pest resistance gene transfer is, however, pest- , region- and cultivar-specific. Resistance of pest to the transgenic crop can still happen Examples of GM Technology Improve yield Crop yield can be increased by modifying growth pattern of the plant parts Typical example is the high-yielding semi-dwarf wheat with the added “Japanese NORIN 10 genes” Two benefits of these dwarfing genes Shorter, stronger plant that could respond to more fertilizer without collapsing Increase yield directly by reducing cell elongation in the plant vegetative plant parts, thereby allowing the plant to invest more in the reproductive plant parts that are eaten These genes can be used to transform other crop species (Peng et al. 1999) Examples of GM Technology Tolerance to Biotic & Abiotic Stresses Most of the examples are concerned with viruses, bacteria & selected soil limiting factors Examples of GM Technology Tolerance to Biotic & Abiotic Stresses These sources of resistance need to be more stable than the traditional intra-species sources Examples of GM Technology Use of Marginalized Lands Marginal lands suffer from different problems including salinity and alkalinity Examples of GM Technology Nutritional Benefits Vitamin A deficiency causes half a million children to become partially or totally blind each year (Conway et. Al. 1999). Researchers introduced 3 genes into rice (2 from daffodils and 1 from a bacterium called Erwinia uredovora). The transgenic rice exhibits an increased production of beta-carotene as a precursor to vitamin A and the seed is yellow in color hence know as golden rice (Ye et al. 2000). See also the February 12, 2001 issue of TIME magazine Examples of GM Technology Examples of GM Technology Nutritional Benefits Iron deficiency causes anemia in pregnant women and young children. About 400 million women of child-bearing age suffer and give birth to underweight children and to mortality at childbirth. Anemia contributes to over 20% of maternal deaths (after giving birth) in Asia and Africa (Conway 1999). Transgenic rice with elevated iron levels has been produced using genes involved in the production of an iron-binding protein and in the production of an enzyme that facilitates iron availability in the human diet (Goto et al. 1999) Examples of GM Technology Reduced Environmental Impacts GM technology is a useful tool for the introduction of root disease resistance for conditions of reduced tillage. This will help reduce soil erosion Examples of GM Technology Pharmaceuticals & Vaccines from Transgenic Plants GM technology has the potential of producing vaccines and pharmaceuticals in plants. This will allow easier access, cheaper production, and an alternative way to generate income. For instance, vaccines against infectious diseases of the gastro-intestinal tract have been produced in potatoes and bananas (Thanavala et al. 1995)
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