Genetic modification of organisms GMOs should be viewed as a technology and blanket statements about how they are bad for human health are not supported by over 30 years of data.
GMOs in agriculture Genetically modified GM foods were first approved for human consumption in the United States inand by —15 about 90 percent of the corncottonand soybeans planted in the United States were GM. By the end ofGM crops covered more than 10 million square kilometres 3.
The majority of GM crops were grown in the Americas. Genetically modified corn maize. For example, the application of wide-spectrum insecticides declined in many areas growing plants, such as potatoescotton, and corn, that were endowed with a gene from the bacterium Bacillus thuringiensis, which produces a natural insecticide called Bt toxin.
Field studies conducted in India in which Bt cotton was compared with non-Bt cotton demonstrated a 30—80 percent increase in yield from the GM crop. Studies of Bt cotton production in Arizona, U.
In China, where farmers first gained access to Bt cotton inthe GM crop was initially successful. Farmers who had planted Bt cotton reduced their pesticide use by 50—80 percent and increased their earnings by as much as 36 percent.
Byhowever, farmers who had been growing Bt cotton for several years found that the benefits of the crop eroded as populations of secondary insect pests, such as mirids, increased. Farmers once again were forced to spray broad-spectrum pesticides throughout the growing seasonsuch that the average revenue for Bt growers was 8 percent lower than that of farmers who grew conventional cotton.
Meanwhile, Bt resistance had also evolved in field populations of major cotton pests, including both the cotton bollworm Helicoverpa armigera and the pink bollworm Pectinophora gossypiella. Other GM plants were engineered for resistance to a specific chemical herbiciderather than resistance to a natural predator or pest.
Herbicide-resistant crops HRC have been available since the mids; these crops enable effective chemical control of weedssince only the HRC plants can survive in fields treated with the corresponding herbicide.
Many HRCs are resistant to glyphosate Roundupenabling liberal application of the chemical, which is highly effective against weeds.
Such crops have been especially valuable for no-till farming, which helps prevent soil erosion. However, because HRCs encourage increased application of chemicals to the soil, rather than decreased application, they remain controversial with regard to their environmental impact.
In addition, in order to reduce the risk of selecting for herbicide-resistant weeds, farmers must use multiple diverse weed-management strategies. Golden rice was created by modifying the rice genome to include a gene from the daffodil Narcissus pseudonarcissus that produces an enzyme known as phyotene synthase and a gene from the bacterium Erwinia uredovora that produces an enzyme called phyotene desaturase.
The introduction of these genes enabled beta-carotene, which is converted to vitamin A in the human liver, to accumulate in the rice endosperm —the edible part of the rice plant—thereby increasing the amount of beta-carotene available for vitamin A synthesis in the body.
In the same researchers who developed the original golden rice plant improved upon the model, generating golden rice 2, which showed a fold increase in carotenoid production.
Another form of modified rice was generated to help combat iron deficiency, which impacts close to 30 percent of the world population. This GM crop was engineered by introducing into the rice genome a ferritin gene from the common beanPhaseolus vulgaris, that produces a protein capable of binding iron, as well as a gene from the fungus Aspergillus fumigatus that produces an enzyme capable of digesting compounds that increase iron bioavailability via digestion of phytate an inhibitor of iron absorption.
The iron-fortified GM rice was engineered to overexpress an existing rice gene that produces a cysteine-rich metallothioneinlike metal-binding protein that enhances iron absorption. A variety of other crops modified to endure the weather extremes common in other parts of the globe are also in production.
Page 1 of 2.Introduction to Genetically Modified Organisms (GMOs) A genetically modified organism (GMO) is an organism or microorganism whose genetic material has been altered to contain a segment of DNA from another organism. Genetically Modified Organisms (GMO): When a gene from one organism is purposely moved to improve or change another organism in a laboratory, the result is a genetically modified organism (GMO).
Genetically modified organisms (GMOs) refer to plants and animals with altered genetic makeups that have been edited in a laboratory to incorporate genes from other organisms. Genetically modified foods (GM foods), also known as genetically engineered foods (GE foods), or bioengineered foods are foods produced from organisms that have had changes introduced into their DNA using the methods of genetic engineering.
Genetically modified organism: Genetically modified organism, organism whose genome has been engineered in the laboratory in order to favor the expression of desired physiological traits or the production of desired biological products.
Learn more about the development and uses of genetically modified organisms in this article. A genetically modified organism (GMO) is an organism whose genetic material has been altered using techniques in genetics generally known as recombinant DNA technology.