Geneticaly Modified Crops
Genetically modified crops (GM crops) are plants used in agriculture, the DNA of which has been modified using genetic engineering methods. In most cases, the aim is to introduce a new trait to the plant which does not occur naturally in the species. Examples in food crops include resistance to certain pests, diseases, environmental conditions, reduction of spoilage, resistance to chemical treatments (e.g. resistance to a herbicide), or improving the nutrient profile of the crop. Examples in non-food crops include production of pharmaceutical agents, biofuels, and other industrially useful goods, as well as for bioremediation.
Farmers have widely adopted GM technology. Acreage increased from 1.7 million hectares in 1996 to 185.1 million hectares in 2016, some 12% of global cropland. As of 2016, major crop (soybean, maize, canola and cotton) traits consist of herbicide tolerance (95.9 million hectares) insect resistance (25.2 million hectares), or both (58.5 million hectares). In 2015, 53.6 million ha of GM maize were under cultivation (almost 1/3 of the maize crop). GM maize outperformed its predecessors: yield was 5.6 to 24.5% higher with less mycotoxins (−28.8%), fumonisin (−30.6%) and thricotecens (−36.5%). Non-target organisms were unaffected, except for Braconidae, represented by a parasitoid of European corn borer, the target of Lepidoptera active Bt maize. Biogeochemical parameters such as lignin content did not vary, while biomass decomposition was higher.
A 2014 meta-analysis concluded that GM technology adoption had reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%.This reduction in pesticide use has been ecologically beneficial, but benefits may be reduced by overuse. Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops.Yield and profit gains are higher in developing countries than in developed countries.
There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, but that each GM food needs to be tested on a case-by-case basis before introduction. however some experiments show that gm crops can cause health risks Nonetheless, members of the public are much less likely than scientists to perceive GM foods as safe. The legal and regulatory status of GM foods varies by country, with some nations banning or restricting them, and others permitting them with widely differing degrees of regulation.
However, opponents have objected to GM crops on grounds including environmental impacts, food safety, whether GM crops are needed to address food needs, whether they are sufficiently accessible to farmers in developing countries and concerns over subjecting crops to intellectual property law. Safety concerns led 38 countries, including 19 in Europe, to officially prohibit their cultivation.
Who Produce Geneticaly Modified Crops?
Most of the research on GM crops has been carried out in developed countries, mainly in North America, Latin America, and Europe. However, many developing countries have also established the capacity for genetic engineering and have several products in the pipeline.
In developed countries, the life sciences companies have dominated the application of GM technology to agriculture.
Transgenic:
Transgenic plants have genes inserted into them that are derived from another species. The inserted genes can come from species within the same kingdom (plant to plant), or between kingdoms (for example, bacteria to plant). In many cases the inserted DNA has to be modified slightly in order to be correctly and efficiently expressed in the host organism. Transgenic plants are used to express proteins, like the cry toxins from B. thuringiensis, herbicide-resistant genes, antibodies, and antigens for vaccinations. A study led by the European Food Safety Authority (EFSA) also found viral genes in transgenic plants.
Transgenic carrots have been used to produce the drug Taliglucerase alfa which is used to treat Gaucher's disease. In the laboratory, transgenic plants have been modified to increase photosynthesis (currently about 2% at most plants versus the theoretic potential of 9–10%). This is possible by changing the rubisco enzyme (i.e. changing C3 plants into C4 plants), by placing the rubisco in a carboxysome, by adding CO
2 pumps in the cell wall, or by changing the leaf form or size. Plants have been engineered to exhibit bioluminescence that may become a sustainable alternative to electric lighting.
2 pumps in the cell wall, or by changing the leaf form or size. Plants have been engineered to exhibit bioluminescence that may become a sustainable alternative to electric lighting.
Cisgenic:
Cisgenic plants are made using genes found within the same species or a closely related one, where conventional plant breeding can occur. Some breeders and scientists argue that cisgenic modification is useful for plants that are difficult to crossbreed by conventional means (such as potatoes), and that plants in the cisgenic category should not require the same regulatory scrutiny as transgenics.
Subgenic:
Genetically modified plants can also be developed using gene knockdown or gene knockout to alter the genetic makeup of a plant without incorporating genes from other plants. In 2014, Chinese researcher Gao Caixia filed patents on the creation of a strain of wheat that is resistant to powdery mildew. The strain lacks genes that encode proteins that repress defenses against the mildew. The researchers deleted all three copies of the genes from wheat's hexaploid genome. Gao used the TALENs and CRISPR gene editing tools without adding or changing any other genes. No field trials were immediately planned. The CRISPR technique has also been used by Penn State researcher Yinong Yang to modify white button mushrooms (Agaricus bisporus) to be non-browning, and by DuPont Pioneer to make a new variety of corn.
A Few Examples of Geneticaly Modified Crops
1)Alfalfa
Alfalfa , also known as lucerne or Medicago sativa, is a plant that has been grown as feed for livestock for hundreds of years.
It was long prized for its superior content of vitamins, minerals and protein, compared to other feed sources .
2) Sugarcane
Sugarcane is an important cash crop of Pakistan. It is mainly grown for sugar and sugary production. It is an important source of income and employment for the farming community of the country. It also forms essential item for industries like sugar, chip board, paper, barrages, confectionery, uses in chemicals, plastics, paints, synthetics, fiber, insecticides and detergents. Sugarcane production in the country has increased over time. In 1988, the area under sugarcane was 878 x 103 hectares which increased to 886 x 103 hectares in 1992 and sugarcane production increased for 36976 x 103 tons in 1988 to 38059 x 103 tons in 1992. Despite expansion in production over years, increase in the productivity per unit of area has been very low in Pakistan. The average sugarcane production in the country required static between 45-50 tons/ha, which is very much low compared to the cane production by other countries. The average yield of sugarcane in the world is around 60 metric tons/ha, while India and Egypt are getting around 66 tons and 105 tons/has, respectively. In this way, Egypt with highest cane yield in the world is getting about 142 per cent high-yield than Pakistan. India with almost similar soil and climatic conditions is obtaining about 53 per cent higher cane yield than Pakistan. As it is one of the cash crops of the country, therefore, efforts should be made to improve its productivity. As a result of these efforts, substantial improvement can take place in its yield. Improved seed production, quality control and distribution depends largely upon the availability of skilled and competent local manpower, which is present in insufficient in most developing countries.
In order to increase the production of sugar cane several steps were taken by the Govt. and the sugar mill association to help formers. In past several reports/research work to increase the production were published on different process which include chemical composition as well as agricultural reforms/steps to increase the recovery and %age yield. Here in this report information is published which can guide local farmers to evaluate their cultivation system and improve it as per requirements.
3) Melon
Melon, (Cucumis melo), trailing vine in the gourd family (Cucurbitaceae), grown for its often musky-scented edible fruit. The melon plant is native to central Asia, and its many cultivated varieties are widely grown in warm regions around the world. Most commercially important melons are sweet and eaten fresh, though some varieties can be made into preserves or pickled.Melons are frost-tender annuals with soft hairy trailing stems and clasping tendrils. They bear large round to lobed leaves and yellow unisexual flowers about 2.5 cm (1 inch) across. Botanically, the fruits are a type of berry known as a pepo, and they vary greatly in size, shape, surface texture, and flesh colour and flavour, depending on the variety. They generally weigh 1–4 kg (2–9 pounds). Cantaloupes and netted melons are ripe when they give off a sweet fruity odour, at which time they “slip,” or break, readily at the union of fruit and stalk. Honeydews and casabas are ripe when they turn yellow, at which time they are cut from the vine. They are called the winter melons because they ripen late and mature slowly in storage for many weeks, becoming softer but not noticeably sweeter. Melon plants are susceptible to a number of diseases, including downy mildew, anthracnose, Fusarium wilt, and powdery mildew, though some varieties are more resistant than others.
4) Rose
Rose, (genus Rosa), genus of some 100 species of perennial shrubs in the rose family (Rosaceae). Roses are native primarily to the temperate regions of the Northern Hemisphere. Many roses are cultivated for their beautiful flowers, which range in colour from white through various tones of yellow and pink to dark crimson and maroon, and most have a delightful fragrance, which varies according to the variety and to climatic conditions.
Most rose species are native to Asia, with smaller numbers being native to North America and a few to Europe and northwest Africa. Roses from different regions of the world hybridize readily, giving rise to types that overlap the parental forms, and making it difficult to determine basic species. Fewer than 10 species, mostly native to Asia, were involved in the crossbreeding that ultimately produced today’s many types of garden roses.
Alfalfa , also known as lucerne or Medicago sativa, is a plant that has been grown as feed for livestock for hundreds of years.
It was long prized for its superior content of vitamins, minerals and protein, compared to other feed sources .
Alfalfa is a part of the legume family, but it's also considered to be an herb.
It seems to have originally come from South and Central Asia, but it has since been grown around the world for centuries.
In addition to being used as feed, it also has a long history of use as a medicinal herb for humans.
Its seeds or dried leaves can be taken as a supplement, or the seeds can be sprouted and eaten in the form of alfalfa sprouts.
2) Sugarcane
Sugarcane is an important cash crop of Pakistan. It is mainly grown for sugar and sugary production. It is an important source of income and employment for the farming community of the country. It also forms essential item for industries like sugar, chip board, paper, barrages, confectionery, uses in chemicals, plastics, paints, synthetics, fiber, insecticides and detergents. Sugarcane production in the country has increased over time. In 1988, the area under sugarcane was 878 x 103 hectares which increased to 886 x 103 hectares in 1992 and sugarcane production increased for 36976 x 103 tons in 1988 to 38059 x 103 tons in 1992. Despite expansion in production over years, increase in the productivity per unit of area has been very low in Pakistan. The average sugarcane production in the country required static between 45-50 tons/ha, which is very much low compared to the cane production by other countries. The average yield of sugarcane in the world is around 60 metric tons/ha, while India and Egypt are getting around 66 tons and 105 tons/has, respectively. In this way, Egypt with highest cane yield in the world is getting about 142 per cent high-yield than Pakistan. India with almost similar soil and climatic conditions is obtaining about 53 per cent higher cane yield than Pakistan. As it is one of the cash crops of the country, therefore, efforts should be made to improve its productivity. As a result of these efforts, substantial improvement can take place in its yield. Improved seed production, quality control and distribution depends largely upon the availability of skilled and competent local manpower, which is present in insufficient in most developing countries.
In order to increase the production of sugar cane several steps were taken by the Govt. and the sugar mill association to help formers. In past several reports/research work to increase the production were published on different process which include chemical composition as well as agricultural reforms/steps to increase the recovery and %age yield. Here in this report information is published which can guide local farmers to evaluate their cultivation system and improve it as per requirements.
3) Melon
Melon, (Cucumis melo), trailing vine in the gourd family (Cucurbitaceae), grown for its often musky-scented edible fruit. The melon plant is native to central Asia, and its many cultivated varieties are widely grown in warm regions around the world. Most commercially important melons are sweet and eaten fresh, though some varieties can be made into preserves or pickled.Melons are frost-tender annuals with soft hairy trailing stems and clasping tendrils. They bear large round to lobed leaves and yellow unisexual flowers about 2.5 cm (1 inch) across. Botanically, the fruits are a type of berry known as a pepo, and they vary greatly in size, shape, surface texture, and flesh colour and flavour, depending on the variety. They generally weigh 1–4 kg (2–9 pounds). Cantaloupes and netted melons are ripe when they give off a sweet fruity odour, at which time they “slip,” or break, readily at the union of fruit and stalk. Honeydews and casabas are ripe when they turn yellow, at which time they are cut from the vine. They are called the winter melons because they ripen late and mature slowly in storage for many weeks, becoming softer but not noticeably sweeter. Melon plants are susceptible to a number of diseases, including downy mildew, anthracnose, Fusarium wilt, and powdery mildew, though some varieties are more resistant than others.
4) Rose
Rose, (genus Rosa), genus of some 100 species of perennial shrubs in the rose family (Rosaceae). Roses are native primarily to the temperate regions of the Northern Hemisphere. Many roses are cultivated for their beautiful flowers, which range in colour from white through various tones of yellow and pink to dark crimson and maroon, and most have a delightful fragrance, which varies according to the variety and to climatic conditions.
Most rose species are native to Asia, with smaller numbers being native to North America and a few to Europe and northwest Africa. Roses from different regions of the world hybridize readily, giving rise to types that overlap the parental forms, and making it difficult to determine basic species. Fewer than 10 species, mostly native to Asia, were involved in the crossbreeding that ultimately produced today’s many types of garden roses.
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Very informative post
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