Genetically Modified (GM) Crops
Genetic modification (GM) is the use of modern biotechnology techniques to change the genes of an organism, such as a plant or animal. As the world’s demand for food continues to increase plant breeders work to breed better yielding crop varieties. They use a range of methods including conventional breeding, mutagenesis, genetic modification, and marker aided selection to breed new improved crop varieties. Genetic modification allows plant breeders to produce a crop variety that could not be bred using conventional breeding.
Plants with favorable characteristics have been produced for thousands of years by conventional breeding methods. Desirable traits are selected, combined and propagated by repeated sexual crossings over numerous generations. This is a long process, taking up to 15 years to produce new varieties. Genetic engineering not only allows this process to be dramatically accelerated in a highly targeted manner by introducing a small number of genes, it can also overcome the barrier of sexual incompatibility between plant species and vastly increase the size of the available gene pool.
Transgenic (GM) plants are those that have been genetically modified using recombinant DNA technology. This may be to express a gene that is not native to the plant or to modify endogenous genes. The protein encoded by the gene will confer a particular trait or characteristic to that plant. The technology can be utilized in a number of ways, for example to engineer resistance to abiotic stresses, such as drought, extreme temperature or salinity, and biotic stresses, such as insects and pathogens, that would normally prove detrimental to plant growth or survival. The technology can also be used to improve the nutritional content of the plant, an application that could be of particular use in the developing world. New-generation GM crops are now also being developed for the production of recombinant medicines and industrial products, such as monoclonal antibodies, vaccines, plastics and biofuels.