Brassica napus

Rapeseed (Brassica napus), also known as rape, oilseed rape, rapa, rappi, rapaseed (and in the case of one particular group of cultivars, canola) is a bright yellow flowering member of the family Brassicaceae (mustard or cabbage family). The name derives from the Latin for turnip, rāpa or rāpum, and is first recorded in English at the end of the 14th century. Older writers usually distinguished the turnip and rape by the adjectives round and long(-rooted) respectively. See also Brassica napobrassica, which may be considered a variety of Brassica napus. Some botanists include the closely related Brassica campestris within B. napus. (See Triangle of U). Rapeseed was the third leading source of vegetable oil in the world in 2000.

Cultivation and uses

In agriculture, canola is the name given to certain varieties of rapeseed oil, or the oil produced from those varieties. Canola is a trademark for a hybrid variety of rape initially bred in Canada ("canola" being an acronym for Canadian oil, low acid). Rapeseed oil was produced in the 19th century as a source of a lubricant for steam engines. It was less useful as food for animals or humans because it has a bitter taste due to high levels of glucosinolates. Canola has been bred to reduce the amount of glucosinolates, yielding a more palatable oil. This has had the side-effect that the oil contains much less erucic acid.

Rapeseed is grown for the production of animal feed, vegetable oil for human consumption, and biodiesel; leading producers include the European Union, Canada, the United States, Australia, China and India. In India, it is grown on 13% of cropped land. According to the United States Department of Agriculture, rapeseed was the third leading source of vegetable oil in the world in 2000, after soybean and oil palm, and also the world's second leading source of protein meal, although only one-fifth of the production of the leading soybean meal.

World production is growing rapidly, with FAO reporting that 36 million tonnes of rapeseed was produced in the 2003-2004 season, and estimates of 58.4 million tonnes in the 2010-2011 season. In Europe, rapeseed is primarily cultivated for animal feed, owing to its very high lipid and medium protein content, and is a leading option for Europeans to avoid importation of genetically modified organism (GMO) products.

Natural rapeseed oil contains 50% erucic acid. Wild type seeds also contain high levels of glucosinolates (mustard oil glucosindes), chemical compounds that significantly lowered the nutritional value of rape seed press cakes for animal feed. Canola, originally a syncopated form of the abbreviation "Can.O., L-A." (Canadian Oilseed, Low-Acid) that was used by the Manitoba government to label the seed during its experimental stages, is now a tradename for "double low" (low erucic acid and low glucosinolate) rapeseed. Sometimes the "Canola-quality" label is affixed to other varieties as well.

The rapeseed is the valuable, harvested component of the crop. The crop is also grown as a winter-cover crop. It provides good coverage of the soil in winter, and limits nitrogen run-off. The plant is ploughed back in the soil or used as bedding. On some ecological or organic operations, livestock such as sheep or cattle are allowed to graze on the plants.

Processing of rapeseed for oil production provides rapeseed animal meal as a by-product. The by-product is a high-protein animal feed, competitive with soya. The feed is mostly employed for cattle feeding, but also for pigs and chickens (though less valuable for these). The meal has a very low content of the glucosinolates responsible for metabolism disruption in cattle and pigs.

Rapeseed "oil cake" is also used as a fertilizer in China, and may be used for ornamentals, such as Bonsai, as well.

Rapeseed leaves and stems are also edible, similar to those of the related bok choy or kale. Some varieties of rapeseed (called , yóu cài, lit. "oil vegetable" in Chinese; yau choy in Cantonese; cải dầu in Vietnamese; phak kat kan khao [ผักกาดก้านขาว] in Thai; and nanohana [菜の花]/nabana [菜花] in Japanese) are sold as greens, primarily in Asian groceries, including those in California where it is known as yao choy or tender greens. They are eaten as sag (spinach) in Indian and Nepalese cuisine, usually stir-fried with salt, garlic and spices.

Rapeseed produces great amounts of nectar, and honeybees produce a light colored, but peppery honey from it. It must be extracted immediately after processing is finished, as it will quickly granulate in the honeycomb and will be impossible to extract. The honey is usually blended with milder honeys, if used for table use or sold as bakery grade. Rapeseed growers contract with beekeepers for the pollination of the crop.

"Total loss" chain and bar oil for chainsaws have been developed which are typically 70% or more canola/rapeseed oil. These lubricants are claimed to be less harmful to the environment and less hazardous to users than traditional mineral oil products, although they are currently typically 2-5x more expensive (leading some to use inexpensive cooking oil instead - see Controversy below). Some countries, such as Austria, have banned the use of petroleum based chainsaw oil. These "bio-lubricants" are generally reported to be functionally comparable to traditional mineral oil products with some reports claiming one or other is superior, but with no overall consensus yet evident.

Biodiesel

Rapeseed oil is used in the manufacture of biodiesel 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. Formerly, owing to the costs of growing, crushing, and refining rapeseed biodiesel, rapeseed derived biodiesel cost more to produce than standard diesel fuel. Rapeseed oil is the preferred oil stock for biodiesel production in most of Europe, accounting for about 80% of the feedstock, partly because rapeseed produces more oil per unit of land area compared to other oil sources, such as soy beans. The majority of European cars and trucks run on diesel fuel and an estimated 66% of total rapeseed oil supply in the European Union is expected to be used for biodiesel production in the 2010-2011 year.

Health effects

Canola oil (or rapeseed oil) contains both omega-6 and omega-3 fatty acids in a ratio of 2:1, although flax oil is higher in omega-3 fatty acid, as are other oils such as Chia (Salvia hispanica) oil. Canola oil's proponents claim that it is one of the most heart-healthy oils and has been reported to reduce cholesterol levels, lower serum tryglyceride levels, and keep platelets from sticking together. While only very long chain omega-3 fatty acids have been shown to improve cholesterol levels, and these are absent from most plant foods, the body can convert some of the short chain into long chain omega 3's.

Rapeseed oil has been linked with adverse effects in asthma and hay fever sufferers. Several scientific studies have identified allergens from pollen . The effects of rape pollen have been brought into question as oilseed rape is an insect pollinated (entomophilous) crop, rather than wind pollinated like grasses and trees, the usual causes of hay fever. An early study showed that relatively small amounts of pollen travel further than 200 metres from the fields of rape . More recently a study has suggested that pollen clouds might travel over longer distances . Others suggest that this is caused by the inhalation of oilseed rape dust, and that allergies to the pollen are relatively rare.

Rapeseed oil contains up to 45% erucic acid. A connection has been found between erucic acid (found in rapeseed and, at much lower levels, canola oil) and autism. "The main findings include increased levels of ... erucic acid ... Our results .... suggest some metabolic or dietary abnormalities in the regressive form of autism." Autism spectrum disorders are the second most common serious developmental disability in the United States.. In 1981 there was a serious outbreak of "Sindrome toxico" where over 1000 people died and 60,000 more were taken seriously ill, with 25,000 suffering long term side effects. This was attributed to Olive Oil being adulterated with rapeseed oil, and in particular the effects of high erucic acid containing rapeseed oil. This has had a long term negative impact on the use of rapeseed and canola oil in Spain. In 2008 there was another outbreak when cattle were fed Canola oil imported from France as a lubricant, where aniline had been added.

Pigs metabolize fats more like humans than rats do and "can be used as a model to evaluate the nutritional and toxicological properties of oils containing erucic acid." Both weaned and unweaned pigs exhibit myocardial lipidosis when fed erucic acid. Bonnet macaque monkeys fed oils containing erucic acid for over a year exhibited sarcoplasmic vacuolation and myocardial fibrosis not found in the control monkeys fed peanut oil or hydrogenated peanut oil. Macaca fascicularis monkeys fed oils containing erucic acid for four months showed myocardial lipidosis, lipidosis of skeletal muscles, and "moth eaten" looking heart fibers. Mitochondria were displaced, distorted, irregular, enlarged, with unclear cristae, and with "amorphous or vacuolated material" in the matrix. When animals were fed erucic acid, myocardial necrosis and/or myocarditis have been found in rats and rabbits, "Trans isomers of α-linolenic acid, which are formed by deodorization of refined vegetable oils, can be found in significant amounts in edible oils." Types and levels of trans fatty acids similar to those that have been found in processed canola have been shown to raise LDL cholesterol levels in humans in just six weeks.

Controversy

The Monsanto Company has genetically engineered new cultivars of rapeseed that are resistant to the effects of its herbicide Roundup. They have sought compensation from farmers found to have the Roundup Ready gene in Canola in their fields without paying a license fee. These farmers have claimed the Roundup Ready gene was blown into their fields and crossed with unaltered Canola. Other farmers claim that after spraying Roundup in non-Canola fields to kill weeds before planting, Roundup Ready volunteers are 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. The case garnered international controversy as a court-sanctioned legitimation for the global patent protection of genetically modified crops. However, Schmeiser was not required to pay damages, as he did not benefit financially from the GMO crop in his field.

In March 2008, an out-of-court settlement between Monsanto and Schmeiser has an agreement for Monsanto to clean up the entire GMO-canola crop on Schmeiser's farm at a cost of $660.

Untreated rapeseed oil/Canola intended for human consumption can be used as an inexpensive "complete loss" chain and bar lubricant for chainsaws, however its efficacy has been the subject of considerable debate on internet forums.

Production

Worldwide production of rapeseed (including canola) has increased sixfold between 1975 and 2007. The production of canola and rapeseed 00 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 diesel. World production is thus expected to trend further upward over between 2005 and 2015 as biodiesel content requirements in Europe go into effect. Every ton of rapeseed yields about 400kg of oil.

{| class="wikitable sortable" |+ Top rapeseed producers (million metric ton) |- ! Country ||1965 ||1975 ||1985||1995||2000||2005|| 2007 || 2009 |- | ||1.1 ||1.5 ||5.6 ||9.8 ||11.3 ||13.0 || align="right"| 10.5 || align="right"| 13.5 |- | ||0.5 ||1.8 ||3.5 ||6.4||7.2 ||9.4 || align="right"| 9.6 || align="right"| 11.8 |- | ||1.5 ||2.3 ||3.1 ||5.8 ||5.8 ||7.6 || align="right"| 7.4 || align="right"| 7.2 |- | ||0.3 ||0.6 ||1.2 ||3.1 ||3.6 ||5.0 || align="right"| 5.3 || align="right"| 6.3 |- | ||0.3 ||0.5 ||1.4 ||2.8 ||3.5||4.5 || align="right"| 4.7 || align="right"| 5.6 |- | ||0.5 ||0.7 ||1.1 ||1.4 ||1.0 ||1.4 || align="right"| 2.1 || align="right"| 2.5 |- | ||<0.007 ||0.06 ||0.9 ||1.2 ||1.2 ||1.9 || align="right"| 2.1 || align="right"| 2.0 |- | ||<0.007 ||<0.06 ||0.1 ||0.6 ||1.8 ||1.4 || align="right"| 1.1 || align="right"| 1.9 |- | ||<0.007 ||<0.06 ||<0.03 ||<0.1||0.1 ||0.3 || align="right"| 1.0 || align="right"| 1.9 |- | ||0.07 ||0.1 ||0.3 ||0.7 ||0.8 ||0.7 || align="right"| 1.0 || align="right"| 1.1 |- | ||<0.007 ||<0.06 ||<0.03 ||0.2 ||0.9 ||0.7 || align="right"| 0.7 || align="right"| 0.7 |- | ||N/A ||N/A ||N/A ||0.1 ||0.1 ||0.3 || align="right"| 0.6 || align="right"| 0.7 |- | ||0.05 ||0.1 ||0.5 ||0.3 ||0.3 ||0.3 || align="right"| 0.6 || align="right"| 0.6 |- | ||N/A ||N/A ||N/A ||0.03 ||0.07 ||0.1 || align="right"| 0.2 || align="right"| 0.6 |- | ||0.008 ||0.1 ||0.1 ||0.1 ||0.2 ||0.3 || align="right"| 0.5 || align="right"| 0.6 |- | ||0.01 ||0.02 ||0.04 ||0.04 ||0.1 ||0.1 || align="right"| 0.4 || align="right"| 0.6 |- |World Total||5.2||8.8 || 19.2||34.2 ||39.5 ||46.4 || align="right"| 50.5 || align="right"| 61.6 |- |colspan=9|Source: UN Food & Agriculture Organisation (FAO) |}

Pests and diseases

Animal pests

Meligethes aeneus

Harlequin bug (Murgantia histrionica)

Flea beetles (Phyllotreta sp.)

Diamondback moths (Plutella xylostella)

Bertha armyworms (Mamestra configurata)

Root maggots (Delia sp.)

Grasshoppers

Lygus bugs (Lygus)

Bronzed field beetle larvae

Snails and slugs

[Cyst nematode] Heterodera schachtii

Diseases

Beet western yellows virus

Blackleg, caused by the fungus Leptosphaeria maculans

Clubroot, caused by protist Plasmodiophora brassicae

Sclerotinia white stem rot

White rust disease, caused by the fungus Albugo candida

Genome sequencing and genetics

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 rapeseed/canola (Brassica napus) and its constituent genomes present in Brassica rapa and Brassica oleracea in 2009. The "A" genome component of the amphidiploid Rapeseed species B. napus is currently being sequenced by the Multinational Brassica Genome Project.

See also

Canola

Biosafety

Transgenic plants

Triangle of U

Brassica

References

External links

PROTAbase on Brassica napus

Canola Council on truth and myths about Canola

Origins of Canola oil is toxic falsehood.

Extracting and refining rapeseed oil

Organisation for Economic Co-operation and Development (05-Dec-2001).Consensus Document on Key Nutrients and Key Toxicants in Low Erucic Acid Rapeseed (Canola). ENV/JM/MONO(2001)13. Retrieved 2006-11-27

University of Melbourne (1999) Multilingual multiscript plant name database. Brassica names. General Botanical Index. Retrieved 2006-11-27

Oilseed rape: Biosafety research funded by the Federal Ministry of Education and Research (BMBF) - Overview

CanolaInfo

BBC Radio 4 Food Programme on rapeseed oil

Category:Brassica Category:Cantonese cuisine Category:Chinese ingredients Category:Energy crops Category:Hong Kong cuisine Category:Edible nuts and seeds Category:Leaf vegetables Category:Medicinal plants Category:Honey plants Category:Fodder