GM Mission Quiz: Genetically Modified Crops Questions

Genetically Modified Crops in Agriculture

Genetically modified crops have had their DNA modified using genetic engineering methods to introduce new traits to the plant that do not naturally occur in the species.
Examples of traits include resistance to pests, diseases, environmental conditions, and chemical treatments, as well as improving the nutrient profile of the crop.
Major crops with genetic modifications include soybean, maize, canola, and cotton.
Farmers have widely adopted GM technology, with acreage increasing from 1.7 million hectares in 1996 to 185.1 million hectares in 2016.
Benefits of GM crops include a reduction in chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%.
GM crops have reduced pesticide poisonings by 2.4 to 9 million cases per year in India alone and led to a 25% decline in farmer suicides in India.
There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food.
Opponents have objected to GM crops on grounds including environmental impacts, food safety, and concerns over subjecting crops to intellectual property law.
Humans have directly influenced the genetic makeup of plants to increase their value as a crop through domestication.
The first genetically engineered crop plant was tobacco in 1983, and the first field trials of genetically engineered plants occurred in France and the US in 1986.
Methods of genetic modification include gene guns, Agrobacterium tumefaciens-mediated transformation, electroporation, and microinjection.
Types of modifications include transgenic, cisgenic, subgenic, and multiple trait integration.Overview of Genetically Modified (GM) Crops
In 2014, approximately 18 million farmers in 28 countries grew biotech crops, with 94% of the farmers being resource-poor in developing countries.
Developing countries accounted for 53% of the global biotech crop area of 181.5 million hectares.
GM crops increased global farm incomes by $14 billion in 2010, with over half going to farmers in developing countries.
The cost of delay for GM crops in developing countries, including GM banana in Uganda, GM cowpea in West Africa, and GM maize/corn in Kenya, is estimated to be $33-46 million annually in Nigeria alone.
Critics challenge the benefits of GM crops, citing biased observers and the absence of randomized controlled trials.
The largest review in 2014 found that GM crops' effects on farming were positive, with herbicide-tolerant crops having lower production costs and insect-resistant crops having reduced pesticide use.
Yield increased 9% for herbicide tolerance and 25% for insect-resistant varieties, with farmers who adopted GM crops making 69% higher profits than those who did not.
GM crops help farmers in developing countries, increasing yields by 14 percentage points.
GM crops have been modified with various traits, including improved shelf life, disease resistance, stress resistance, herbicide resistance, pest resistance, and toxin reduction.
The first GM crop approved for sale in the US was the FlavrSavr tomato, which had a longer shelf life.
Insects and viral pathogens have been the focus of GM pest resistance, with crops such as tobacco, corn, rice, and squash being engineered to resist them.
GM crops have reduced the total volume of insecticide active ingredient use in the US by over 100 thousand tons, representing a 19.4% reduction in insecticide use.Overview of Genetically Modified Plants
Virus-resistant papaya were developed in response to a papaya ringspot virus outbreak in Hawaii in the late 1990s and by 2010, 80% of Hawaiian papaya plants were genetically modified.
Potatoes were engineered for resistance to potato leaf roll virus and Potato virus Y in 1998 but were withdrawn from the market after three years due to poor sales.
Yellow squash that were resistant to three viruses were developed beginning in the 1990s and became the second GM crop to be approved by US regulators, and the trait was later added to zucchini.
Many strains of corn have been developed to combat the spread of Maize dwarf mosaic virus, although the resistance is not standard among GM corn variants.
Tobacco plants have been modified to produce therapeutic antibodies, and algae is under development for use in biofuels.
Companies and labs are working on plants that can be used to make bioplastics, and potatoes have been modified to produce industrially useful starches.
Crops such as maize reproduce sexually each year, which randomizes the genes that get propagated to the next generation, so genetic engineering offers a way to maintain a high-quality crop by allowing farmers to replant harvested seeds that retain desirable traits.
The number of USDA-approved field releases for testing grew from 4 in 1985 to 1,194 in 2002, and releases with agronomic properties jumped from 1,043 in 2005 to 5,190 in 2013.
By 2006, some weed populations had evolved to tolerate some herbicides, and resistance appears to be developing to some Bt traits in some areas.
Farmers generally use less insecticide when they plant Bt-resistant crops, and conservation tillage reduces soil erosion from wind and water, increases water retention, and reduces soil degradation.
In 2013, GM crops were planted in 27 countries, and 18 million farmers grew GM crops; around 90% were small-holding farmers in developing countries.
Between 1996 and 2013, the total surface area of land cultivated with GM crops increased by a factor of 100, from 17,000 square kilometers to 1,750,000 km2.
By 2014, 94% of the planted area of soybeans, 96% of cotton, and 93% of corn in the US were genetically modified varieties.Overview of Genetically Modified Crops
Soybeans, maize, and cotton are the most common genetically modified (GM) crops, with herbicide tolerance and insect protection traits.
In the US, 70-75% of processed foods contain GM ingredients.
Europe grows relatively few GM crops, with Spain being the exception.
In 2013, developing countries grew 54% of worldwide GM crops, with Brazil and India having the largest increases.
A total of 36 countries have granted regulatory approval for GM crops, with maize having the largest number of approved crops.
GM crops have been controversial due to environmental impacts, food safety concerns, accessibility to farmers, intellectual property laws, religious beliefs, labeling, and pesticide use.
Environmental concerns include possible cross-breeding with related crops, giving them advantages over naturally occurring varieties.
There is a scientific consensus that GM food is safe for human consumption, but public perception differs.
The legal and regulatory status of GM foods varies by country.
No ill effects from GM food have been documented in the human population.
Advocacy groups claim that risks related to GM food have not been adequately examined and managed and that regulatory authorities and scientific bodies are too closely tied to industry.
Some studies have claimed that genetically modified crops can cause harm, but a 2016 review found their statistical methodologies to be flawed.