What Is Rapeseed: Information About Rapeseed Benefits And History
By: Liz Baessler
While they have a very unfortunate name, rape plants are widely grown the world over for their extremely fatty seeds that are used both for nutritious animal feed and for oil. Keep reading to learn more about rapeseed benefits and growing rape plants in the garden.
What is rapeseed? Rape plants (Brassica napus) are members of the brassica family, which means they’re closely related to mustard, kale, and cabbage. Like all brassicas, they are cool weather crops, and growing rape plants in the spring or autumn is preferable.
The plants are very forgiving and will grow in a wide range of soil qualities as long as it is well-draining. They will grow well in acidic, neutral, and alkaline soils. They will even tolerate salt.
Rape plants are almost always grown for their seeds, which contain a very high percentage of oil. Once harvested, the seeds can be pressed and used for cooking oil or non-edible oils, such as lubricants and biofuels. The plants harvested for their oil are annuals.
There are also biennial plants that are mainly grown as feed for animals. Because of the high fat content, biennial rape plants make an excellent feed and is often used as forage.
Rapeseed vs. Canola Oil
While the words rapeseed and canola are sometimes used interchangeably, they are not quite the same thing. While they belong to the same species, canola is a specific cultivar of the rape plant that is grown to produce food grade oil.
Not all varieties of rapeseed are edible for humans due to the presence of erucic acid, which is especially low in canola varieties. The name “canola” was actually registered in 1973 when it was developed as an alternative to rapeseed for edible oil.
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- 1 Etymology and taxonomy
- 2 Description
- 3 Ecology
- 4 Uses
- 4.1 Animal feed
- 4.2 Vegetable oil
- 4.3 Biodiesel
- 4.4 Other
- 5 Cultivation
- 6 Diseases and pests
- 6.1 Pests
- 7 History of the cultivars
- 7.1 GMO cultivars
- 8 Production
- 9 See also
- 10 Notes
- 11 References
- 11.1 Sources
The term "rape" derives from the Latin word for turnip, rapa or rapum, cognate with the Greek word rhapys. 
The species Brassica napus belongs to the flowering plant family Brassicaceae. Rapeseed is a subspecies with the autonym B. napus subsp. napus.  It encompasses winter and spring oilseed, vegetable and fodder rape.  Siberian kale is a distinct leaf rape form variety (B. napus var. pabularia) which used to be common as a winter-annual vegetable.   The second subspecies of B. napus is B. napus subsp. rapifera (also subsp. napobrassica the rutabaga, swede, or yellow turnip).  
Brassica napus is an digenomic amphidiploid that occurred due to the interspecific hybridization between Brassica oleracea and Brassica rapa.  It is a self-compatible pollinating species like the other amphidiploid brassica species. 
Brassica napus grows to 100 cm (39 in) in height with hairless, fleshy, pinnatifid and glaucous lower leaves    which are stalked whereas the upper leaves have no petioles.  Brassica napus can be distinguished from Brassica nigra by the upper leaves which do not clasp the stem, and from Brassica rapa by its smaller petals which are less than 13 mm (0.51 in) across. 
Rapeseed flowers are yellow and about 17 mm (0.67 in) across.  They are radial and consist of four petals in a typical cross-form, alternating with four sepals. They have indeterminate racemose flowering starting at the lowest bud and growing upward in the following days. The flowers have two lateral stamens with short filaments, and four median stamens with longer filaments whose anthers split away from the flower's center upon flowering . 
The rapeseed pods are green and elongated siliquae during development that eventually ripen to brown. They grow on pedicels 1 to 3 cm long, and can range from 5 to 10 cm in length.  Each pod has two compartments separated by an inner central wall within which a row of seeds develop.  The seeds are round and have a diameter of 1.5 to 3mm. They have a reticulate surface texture,  and are black and hard at maturity. 
In Northern Ireland, U K B. napus and B. rapa are recorded as escapes in roadside verges and waste ground. 
Rapeseed is grown for the production of animal feed, edible vegetable oils, and biodiesel. Rapeseed was the third-leading source of vegetable oil in the world in 2000, after soybean and palm oil.  It is the world's second-leading source of protein meal after soybean. 
Animal feed Edit
Processing of rapeseed for oil production produces rapeseed meal as a byproduct. The byproduct is a high-protein animal feed, competitive with soybean. The feed is employed mostly for cattle feeding, but is also used for pigs and poultry.  However, natural rapeseed oil contains 50% erucic acid and high levels of glucosinolates that significantly lowers the nutritional value of rapeseed press cakes for animal feed. 
Vegetable oil Edit
Rapeseed oil is one of the oldest known vegetable oils, but historically was used in limited quantities due to high levels of erucic acid, which is damaging to cardiac muscle of animals, and glucosinolates, which made it less nutritious in animal feed.  Rapeseed oil can contain up to 54% erucic acid.  Food-grade canola oil derived from rapeseed cultivars, also known as rapeseed 00 oil, low erucic acid rapeseed oil, LEAR oil, and rapeseed canola-equivalent oil, has been generally recognized as safe by the United States Food and Drug Administration.  Canola oil is limited by government regulation to a maximum of 2% erucic acid by weight in the USA  and 5% in the EU,  with special regulations for infant food. These low levels of erucic acid are not believed to cause harm in human infants.  
Rapeseed oil is used as diesel fuel, either as biodiesel, straight in heated fuel systems, or blended with petroleum distillates for powering motor vehicles. Biodiesel may be used in pure form in newer engines without engine damage and is frequently combined with fossil-fuel diesel in ratios varying from 2% to 20% biodiesel. Owing to the costs of growing, crushing, and refining rapeseed biodiesel, rapeseed-derived biodiesel from new oil costs more to produce than standard diesel fuel, so diesel fuels are commonly made from the used oil. Rapeseed oil is the preferred oil stock for biodiesel production in most of Europe, accounting for about 80% of the feedstock, [ citation needed ] partly because rapeseed produces more oil per unit of land area compared to other oil sources, such as soybeans, but primarily because canola oil has a significantly lower gel point than most other vegetable oils.
Rapeseed is also used as a cover crop in the US during the winter as it prevents soil erosion, produces large amounts of biomass, suppresses weeds and can improve soil tilth with its root system. Some cultivars of rapeseed are also used as annual forage and are ready for grazing livestock 80 to 90 days after planting. 
Rapeseed has a high melliferous potential and is a main forage crop for honeybees.  Monofloral rapeseed honey has a whitish or milky yellow color, peppery taste and, due to its fast crystallization time, a soft-solid texture. It crystallizes within 3 to 4 weeks and can ferment over time if stored improperly.  The low fructose-to-glucose ratio in monofloral rapeseed honey causes it to quickly granulate in the honeycomb, forcing beekeepers to extract the honey within 24 hours of it being capped. 
As a biolubricant, rapeseed has possible uses for bio-medical applications (e.g., lubricants for artificial joints) and the use of personal lubricant for sexual purposes.  Biolubricant containing 70% or more canola/rapeseed oil has replaced petroleum-based chainsaw oil in Austria although they are typically more expensive. 
Rapeseed has been researched as a means of containing radionuclides that contaminated the soil after the Chernobyl disaster   as it has a rate of uptake up to three times more than other grains, and only about 3 to 6% of the radionuclides go into the oilseeds. 
Rapeseed meal is mostly used as a soil fertilizer rather than for animal feed in China. 
Crops from the genus Brassica, including rapeseed, were among the earliest plants to be widely cultivated by mankind as early as 10,000 years ago. Rapeseed was being cultivated in India as early as 4000 B.C. and it spread to China and Japan 2000 years ago. 
Rapeseed oil is predominantly cultivated in its winter form in most of Europe and Asia due to the requirement of vernalization to start the process of flowering. It is sown in autumn and remains in a leaf rosette on the soil surface during the winter. The plant grows a long vertical stem in the next spring followed by lateral branch development. It generally flowers in late spring with the process of pod development and ripening occurring over a period of 6–8 weeks until midsummer. 
In Europe, winter rapeseed is grown as an annual break crop in three to four-year rotations with cereals such as wheat and barley, and break crops such as peas and beans. This is done to reduce the possibility of pests and diseases being carried over from one crop to another.  Winter rape is less susceptible to crop failure as it is more vigorous than the summer variety and can compensate for damage done by pests. 
Spring rapeseed is cultivated in Canada, northern Europe and Australia as it is not winter-hardy and does not require vernalization. The crop is sown in spring with stem development happening immediately after germination. 
Rapeseed can be cultivated on a wide variety of well-drained soils, prefers a pH between 5.5 and 8.3 and has a moderate tolerance of soil salinity.  It is predominantly a wind-pollinated plant but shows significantly increased grain yields when bee-pollinated,  almost double the final yield  but the effect is cultivar-dependent.  It is currently grown with high levels of nitrogen-containing fertilisers, and the manufacture of these generates N2O. An estimated 3-5% of nitrogen provided as fertilizer for rapeseed is converted to N2O. 
The main diseases of the winter rapeseed crop are canker, light leaf spot, alternaria and sclerotinia stem rot. Canker causes leaf spotting, and premature ripening and weakening of the stem during the autumn-winter period. A conazole or triazole fungicide treatment is required in late autumn and in spring against canker while broad-spectrum fungicides are used during the spring-summer period for alternaria and sclerotinia control.  Oilseed rape cannot be planted in close rotation with itself due to soil-borne diseases such as sclerotinia, verticillium wilt and clubroot. 
Rapeseed is attacked by a wide variety of insects, nematodes, slugs as well as wood pigeons.  The brassica pod midge, cabbage seed weevil, cabbage stem weevil, cabbage stem flea beetle, rape stem weevil and pollen beetles are the primary insect pests that prey on the oilseed rape crop in Europe.  The insect pests can feed on developing pods to lay eggs inside and eat the developing seeds, bore into the plant's stem and feed on pollen, leaves and flowers. Synthetic pyrethroid insecticides are the main attack vector against insect pests though there is a large-scale use of prophylactic insecticides in many countries.  Molluscicide pellets are used either before or after sowing of the rapeseed crop to protect against slugs. 
In 1973, Canadian agricultural scientists launched a marketing campaign to promote canola consumption.  Seed, oil and protein meal derived from rapeseed cultivars which is low in erucic acid and low in glucosinolates was originally registered as a trademark, in 1978, of the Canola Council of Canada, as "canola".   This is now a generic term for edible varieties of rapeseed but is still officially defined in Canada as rapeseed oil that "must contain less than 2% erucic acid and less than 30 µmol of glucosinolates per gram of air-dried oil-free meal."  
Following the European Parliament's Transport Biofuels Directive in 2003 promoting the use of biofuels, the cultivation of winter rapeseed increased dramatically in Europe. 
Bayer Cropscience, in collaboration with BGI-Shenzhen, China, Keygene N.V., the Netherlands, and the University of Queensland, Australia, announced it had sequenced the entire genome of B. napus and its constituent genomes present in B. rapa and B. oleracea in 2009. The "A" genome component of the amphidiploid rapeseed species B. napus is currently being sequenced by the Multinational Brassica Genome Project.  [ needs update ]
A genetically modified-for-glyphosate-tolerance variety of rapeseed which was developed in 1998 is considered to be the most disease- and drought-resistant canola. By 2009, 90% of the rapeseed crops planted in Canada were of this sort,  adoption of which, however, has not been free of controversy.
GMO cultivars Edit
The Monsanto company genetically engineered new cultivars of rapeseed to be resistant to the effects of its herbicide, Roundup. In 1998, they brought this to the Canadian market. Monsanto sought compensation from farmers found to have crops of this cultivar in their fields without paying a license fee. However, these farmers claimed that the pollen containing the Roundup Ready gene was blown into their fields and crossed with unaltered canola. Other farmers claimed that after spraying Roundup in non-canola fields to kill weeds before planting, Roundup Ready volunteers were left behind, causing extra expense to rid their fields of the weeds. 
In a closely followed legal battle, the Supreme Court of Canada found in favor of Monsanto's patent infringement claim for unlicensed growing of Roundup Ready in its 2004 ruling on Monsanto Canada Inc. v. Schmeiser, but also ruled that Schmeiser was not required to pay any damages. The case garnered international controversy, as a court-sanctioned legitimization for the global patent protection of genetically modified crops. In March 2008, an out-of-court settlement between Monsanto and Schmeiser agreed that Monsanto would clean up the entire GMO-canola crop on Schmeiser's farm, at a cost of about CAD $660. 
The Food and Agriculture Organization reports global production of 36 million tons of rapeseed in the 2003–2004 season, and an estimated 58.4 million tons in the 2010–2011 season. 
Worldwide production of rapeseed (including canola) has increased sixfold between 1975 and 2007. The production of canola and rapeseed since 1975 has opened up the edible oil market for rapeseed oil. Since 2002, production of biodiesel has been steadily increasing in EU and USA to 6 million metric tons in 2006. Rapeseed oil is positioned to supply a good portion of the vegetable oils needed to produce that fuel. World production was thus expected to trend further upward between 2005 and 2015 as biodiesel content requirements in Europe go into effect. 
Foods, Materials, Technologies and Risks
The Use of GM Technology in Agriculture and Foods
Canola (Canadian oil, low acid) for human consumption was developed in the early 1970s in Manitoba through conventional plant breeding from rapeseed to distinguish it from natural rapeseed oil, which has much higher erucic acid content. By 1998, a more disease- and drought-resistant variety was developed through genetic engineering. In the present day, Canola is produced widely in Canada, the US, and other countries, and it is generally recognized as safe by the United States Food and Drug Administration (USFDA), and in 2013 was permitted in infant formulas with Canola oil at levels up to 31% of the total fat blend.
Other widely consumed GM products are corn and soybeans from GM crops. The herbicide glyphosate inhibits the enzyme 5-enolpyruvylshikimate-3-phosphate synthase, which is present in plants, fungi, and bacteria but not in animals. This enzyme is a key step in the formation of hormones through production of aromatic amino acids. The use of the broad-spectrum herbicide became much more widespread with the development of Roundup® ready (GM) soybeans and maize, which contained the glyphosate-N-acetyltransferase gene. With the application of the herbicide, these GM crops would not be affected, but certain weeds would be killed. In the present day, different commercial glyphosate products are able to control more than 100 broadleaf and grass varieties of weeds. Toxicological studies showed that even though new metabolites are formed in the edible parts of the GM crops that were not observed in conventional crops, the Joint FAO/WHO Meeting on Pesticide Residues concluded there was no human health concerns for the short- or long-term consumption of these commodities or their products. The number of approved GM crops worldwide is expected to increase from 30 in 2009 to 110 by 2015. Even in Europe where concern by the population to GM foods is greatest, approximately 30 million tons of GM crops are imported each year and many varieties of herbicide-resistant maize are now allowed to be grown in the European Union (EU). However, glyphosate is only slowly degraded by soil microorganisms and may pose a risk of water contamination. In addition, resistance of some species of weeds to the herbicide is a growing concern.
Another successful application of GM technology is the insertion of a gene for the biological pesticide produced by Bacillus thuringiensis (Bt), a close relative of the very common soil and dust bacterium Bacillus cereus. In 1901, Bt was first observed in a colony of sick or dying silkworms in Japan. The main difference between Bt and B. cereus is that Bt produces an endotoxin that kills lepidoptera. This is accomplished by the protein toxin, which occurs as a parasporal body (‘crystal’) in the bacterium during sporulation. The insect gut proteases activates the toxin proteins, allowing them to bind to receptors, and affect the midgut cells by forming pores in the larval digestive tract (hemocoel). These pores allow naturally occurring enteric bacteria to enter the hemocoel, where they multiply and cause sepsis The Bt toxin in the form of spray-dried wettable powder of the Bt culture became commercially available in the 1950s and was used extensively in Canada in a spray over wide areas of forests infested by spruce budworm and gypsy moth. In forestry, however, by the mid-1980s, Bt strains had virtually replaced the major chemical pesticides for spruce budworm and gypsy moth control in Ontario, Quebec, and the Atlantic provinces. Since then, various modifications have been made to target certain insects, mainly destructive caterpillars. However, for food and forage crops, its use has been more limited, mainly targeted against cabbage worms, tomato hornworm, European corn borer, alfalfa caterpillar, and alfalfa webworm. Bt can be applied through overhead irrigation systems or as granules. Available data suggest that spores may remain in soil from months to years under field conditions, but little is known about the longevity of the toxin in soil or water.
Two isolates of this genus are highly active against insects of great economic importance Bt subsp. kurstaki attacks lepidopterous insects and Bt subsp. israelensis kills mosquitoes and black flies. The Bt kurstaki strain is the one used most frequently as a spray to control caterpillars on vegetables. Bt insecticides are the only bacterial insecticides in widespread use, and one advantage they have is that they neither target pollinators, like bees, nor predators or parasites of the pests of concern. In 2012, the European Food Safety Authority conducted a risk assessment on the Bt kurstaki strain and concluded that the health risk to mammals, reptiles, amphibians, birds, algae, and nonlepidoptera terrestrial arthropods, and probably soil microorganisms is low. From a GMO perspective, Bt maize is a variant of maize, genetically altered by inserting the gene for Bt toxin into the maize genome to kill European maize borer and more recently the maize ear worm and root worm. Unlike Bt, transgenic plants like corn do not release the Bt toxin. Instead, the cell must be digested by the insect in order to release the active ingredient in the gut. This is an improvement on the sprayed Bt because it is not susceptible to degradation by sunlight or washed away by rain. Most sprayed formulations are less effective over time, perhaps a few days or weeks after application, unlike the GM version, which is effective for the life of the plant. One risk however, is that continual exposure of insects to the GM derived Bt may confer resistance to insect predation.
Although insects are capable of developing high levels of resistance under laboratory experiments, this has not been observed to any great extent where crops have been sprayed. Now it is generally agreed that ‘high dose/refuge strategy’ is the most promising and practical approach to prolong the effectiveness of Bt toxins. This requires toxin free host plants as refuges near insecticidal crops, and toxin doses intended to be sufficiently high to kill insects. After more than a decade because of initial commercialization of Bt crops, most target pest populations remain susceptible, but field-evolved resistance has been documented in some populations of three noctuid moth species feeding on Bt maize in Puerto Rico and South Africa and in Bt cotton in the southeastern US. Field outcomes are consistent with predictions from theory, suggesting that factors delaying resistance include recessive inheritance of resistance, abundant refuges of nonBt host plants, and two-toxin Bt crops deployed separately from one-toxin Bt crops. The use of Bt crops is popular worldwide with more than 32 million hectares in cultivation, including Bt cotton and Bt potatoes. Even some countries with concerns about GM foods in general, such as in the EU, permit the use of Bt transgenic crops, and it is likely their use will expand in the future. Other GMOs permitted in the US and some other countries include cotton resistant to the herbicide bromoxynil delayed ripening tomatoes squash, zucchini, and papaya modified to resist viruses (80% of Hawaiian papaya is genetically engineered because there is still no conventional or organic method to control ringspot virus). Sugar beets that are glyphosate resistant have been approved in Australia, Canada, Colombia, EU, Japan, Korea, Mexico, New Zealand, Philippines, Russian Federation, Singapore, and the US.
The potential of this technology can also be used to enhance nutrition such as vitamin production a good example of this is ‘golden rice’, a GM variety of Oryza sativa rice, which produces beta-carotene, a precursor of vitamin A, in the edible parts of rice, produced in 2000. Golden rice was created by transforming rice with two beta-carotene biosynthesis genes: Phytoene synthase from a daffodil and crtI from an Erwinia species, and actually is golden in color, quite distinct from nonGM rice. The reason for the research was to plant this variety in regions, such as in Africa and India, where thousands of children die each year from a lack of vitamin A. In 2005, a newer variety producing much more beta-carotene was developed, but unfortunately neither the original nor the newer version is yet grown for human consumption. The GM crop approach for vitamin A fortification is seen by many as a less expensive and more practical alternative to vitamin supplements or a change in diet to greater consumption of vegetables and animal products.
The usual concerns expressed about GM crops have also been raised in regard to golden rice: spread of GM genes into the environment loss of local varieties and biodiversity opening the door to more controversial GMOs obscene profits made by multinational companies from those who can least afford the cost of the seed and vitamin A could be derived from other food sources. Other opponents have argued that adults and children would have to eat inordinate amounts of golden rice to see any benefit. However, recent trials showed that golden rice delivered dietary vitamin A as good as supplements and better than the natural beta-carotene in spinach. To permit widespread use, GM companies have now agreed that farmers could obtain the seed and replant it free of charge, unless they made more than USD$10 000 a year from the crop. Field trials have been conducted, and it is hoped that golden rice will meet the regulatory conditions for its production and be on the market in 2015.
Another beneficial application of GM technology is vaccine production and delivery through GM plants. Selected DNA from hepatitis B and cholera viruses injected into banana saplings might allow the plant to produce antigenic proteins without any infectivity component. Consumption of these bananas (and some other modified vegetables like potatoes and carrots) would build up antibodies in the consumer to fight these diseases in a similar way to injecting or ingesting traditional vaccine. This may be a more efficient and less costly way of vaccinating large populations against specific diseases.
GM research with plants will accelerate in the future, and some of the outcomes may prove to be both economically and environmentally acceptable to governments and the public. Some plants and trees could be engineered for capturing large amounts of carbon, which would be sequestered in roots and stems. Perennial grasses like switchgrass and Miscanthus may have the best immediate potential because of their extensive root systems. Other examples are GM trees to grow faster yield better wood, say for construction and for biofuel resist pest invasion and extreme climatic conditions and even detect biological attacks by developing trees that change color when exposed to biological or chemical contamination. However, environmental concerns will prevent any large scale adoption of these, particularly as pollen released from trees is uncontrollable over large areas.