Brassica rapa
(field mustard)

Preferred Common Name

• field mustard

Other Scientific Names

• Barbarea derchiensis S.S.Ying
• Brassica antiquorum H.Lév
• Brassica asperifolia Lam.
• Brassica brassicata A.Chev.
• Brassica briggsii Varenne
• Brassica campestris L.
• Brassica celerifolia (Tsen & S.H. Lee) Y.Z.Land & T.Y.Cheo
• Brassica chinensis L.
• Brassica cibaria Dierb.
• Brassica colza H.Lév.
• Brassica cyrenaica Spreng.
• Brassica dubiosa L.H.Bailey
• Brassica macrorhiza Gray
• Brassica napella Chaix
• Brassica narinosa L.H.Bailey
• Brassica nipposinica L.H.Bailey
• Brassica oleronensis A.Sav. ex Foucaud
• Brassica parachinensis L.H.Bailey
• Brassica pekinensis (Lour.) Rupr.
• Brassica pekinensis Skeels
• Brassica perfoliata Crantz
• Brassica perviridis (L.H.Bailey) L.H.Bailey
• Brassica petsai (Lour.) L.H.Bailey
• Brassica pseudocolza H.Lév
• Brassica purpuraria (L.H.Bailey) L.H.Bailey
• Brassica quadrivalvis Hook.f. & Thomson
• Brassica rapifera (Metzg.) Dalla Torre & Sarnth.
• Brassica rapoasiatica Sinskaya
• Brassica rapoeuropea Sinskaya
• Brassica saruna Siebold
• Brassica septiceps (L.H.Bailey) L.H.Bailey
• Brassica sphaerorrhiza Gray
• Brassica trilocularis Hook.f. & Thomson
• Brassica trimestris Boenn.
• Brassica tuberosa Salisb.
• Caulanthus sulfureus Payson
• Crucifera rapa E.H.L.Krause
• Napus campestris (L.) Schimp. & Spenn.
• Napus rapa (L.) Schimp. & Spenn.
• Raphanus campestris (L.) Crantz
• Raphanus rapa (L.) Crantz
• Sinapis dichotoma Roxb.
• Sinapis pekinensis Lour.
• Sinapis rapa (L.) Brot.
• Sinapis tuberosa Poir.

International Common Names

• English: Chinese savoy; biennial turnip rape; bird rape; bird’s rape; birdrape mustard; bok choi; bomdong; broad-beak mustard; brown sarson; caisim; caisin; cai-xin; canola; celery cabbage; Chinese cabbage; Chinese mustard; Chinese white cabbage; choisum; choi-sum; colbaga; colza; common turnip; dwarf white stem pak choy; false pak choi; flowering white cabbage; fodder kale; hanover salad; Indian colza; Indian rape; Italian kale; Italian turnip broccoli; komatsuna; leaf rape; mizuna; mustard cabbage; mustard spinach; napa cabbage; nep crops; pakchoi; pak-choi; petsai; pe-tsai; Polish canola; rape; rapini; rosette pak choi; ruvo kale; seven-top turnip; shantung cabbage; Siberian kale; spring turnip rape; stubble turnip; summer turnip rape; Swedish turnip; tat soi; turnip; tyfon; white celery mustard; white turnip; wild mustard; wild rutabaga; wild turnip; winter turnip; winter turnip rape; yellow sarson
• Spanish: col de China; colza; mostaza blanca; nabina; nabo; nabo gallego; repollo chino; yuyo
• French: navet blanc; pakchoï; pétsaï; brocoli chinois; chou Chinois; chou de Chine; chou de Shanghai; chou de shanton; chou-navet; choy sum; moutarde des oiseaux; moutarde épinard; navet; navette d’hiver; navette sauvage; pakchoy; rave; roquette d’orient
• Portuguese: couve Chinesa; couve d’inflorescência; couve da China; couve petsai; nabo; rábano

Local Common Names

• Persian Gulf States: latok
• Afghanistan: shalgham
• Australia: wombok
• Azerbaijan: turp
• Bolivia: k’ita mostacilla; k’ita nabo; navo
• Brazil: couve-chinesa-petsai; couve-repolho-da-china; nabo-selvagem; nabo-silvestre
• Bulgaria: repitsa
• Cambodia: Pe-chhaay; Spéi khiew
• Canada: Annual turnip rape; Argentine canola; Polish rape
• China: bai cai; bo leng jie; da ge cai; man jing; qing cai; qing cai pak choi; sui choi; ta ke cai; taatsai; wang sheng cai; xi yang you cai; xiqo you cai; yun tai; ze cai hua; ze tai cai; zi cai tai
• Colombia: mostaza silvestre; alpiste
• Denmark: höstoe; knakaal; majroe
• Ecuador: nabo chino
• Finland: pakchoi; pe-tsai; pinaattikiinankaali; rapsi
• Germany: Chinakohl; Chinesischer senf-kohl; Herbstrübe; Kohlrübe; Mairübe; Pakchoi; Rübsaat; Rübsen; Schnittkohl; Speiserübe; Steckrübe; Stoppelrübe; Wasserrübe; Weiße Rübe; Wruke
• Haiti: chou; navet
• India: an-tam; chalgom; grunjanakam; kalamohare; kali sarson; katusneha; nalla avalu; salgam; sarisan; sarsapa; sarson; shalgam; shaljam; sherasa; tantubha; tori; toria
• Indonesia: caisin; paksoi; pecai; sawi hijau; sawi kembang; sawi putih
• Italy: broccoletto; cime di rapa; colza; navete; navone; rapa; rapaccio; ravizzone
• Japan: hakusai; kabu; kabuna; kisaragina; kyona; mibuna; mizuna; natane; shakushina; taasai; taisi; turnip greens
• Laos: kaas chiin
• Malaysia: kobis cina; pak choi; petsai; sawi bunga; sawi puhit
• Mexico: flor de nabo; huachelai; mostacilla; mostaza; nabo de campo; nabo de canarios; nabo silvestre; pata de cuervo; semilla para pájaros; vaina
• Moldova: turneps
• Nepal: gante mula; salgam
• Netherlands: chinesekool; koolzaad
• New Caledonia: navet
• New Zealand: won bok; wong bok
• Norway: kålrot
• Pakistan: gonglu; shaljam
• Papua New Guinea: kapis
• Philippines: Chinese cabbage; dagawan; pechai baguio; pechay; wombok
• Poland: brukiew
• Portugal: couve nabiça de grelo; couve nabo; couve nabo branca; nabo redondo; turnepo
• Russian Federation: brjukva; kapusta kitajskaja; kapusta polevaya; kol’za; raps; repa; superitsa; surepica; turneps
• Spain: berza campía; berza silvestre; cabeza de nabo; carola; colinabo; grela; grelo; naba; nabicol; nabilla; nabina; nabiza; nabo forrajero; nabo galego; nabo gallego; nabo largo; nabo redondo; nabos; nap rodó; nap-i-col; raba
• Sweden: åkerkål; kohlraps; raps; rofraps; rofva; rova
• Thailand: phakkat-kheokwangtung; hong-how; hong-tae; phakkat-khaokwangtung; phakkat-khaopli; phakkat-khaoyai; phakkwangtung
• Turkey: chordal
• UK: Chinese leaf
• Ukraine: kapusta polova; ripa
• USA: asian greens; California peppergrass; common mustard; forage turnip; Japanese mustard; mibuna; mizuna; potherb mustard; rape mustard; summer turnip; turnip rape
• Vietnam: cari bawsc kinh; cari bej trawsng; cari ngojt; cari thiaf

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Capparidales
•                         Family: Brassicaceae
•                             Genus: Brassica
•                                 Species: Brassica rapa

The Brassicaceae, known as the mustard family, is composed of about 3740 species within 325 genera (Koch et al., 2012; Kiefer et al., 2014; Koch et al., 2018). It includes many economically important species, mostly in the genus Brassica, with some species being among the oldest cultivated plants. Brassica is the biggest genus of the family, providing oils, vegetables and condiments as well as being used as a fodder (PFAF, 2018).

Brassica rapa is one of the oldest Brassicaceae domesticated for oil production, as a vegetable and as a fodder (PROTA, 2018). The species exhibits high levels of morphological variation, with a long history of breeding and selection (Lou et al., 2007). Several infraspecific classifications have been proposed; more than 140 names appear in The Plant List (2013). Some of the morphotypes most common in cultivation include oilseed (B. rapa subsp. oleifera (rape), B. rapa subsp. dichotoma (brown sarson or toria) and B. rapa subsp. trilocularis, (yellow sarson)), leafy vegetables (B. rapa subsp. pekinensis (Chinese cabbage), B. rapa subsp. chinensis (pakchoi) and B. rapa subsp. nipposinica (mizuna)), root vegetables (Brassica rapa subsp. rapa (turnip)), and fodder crops (Guo et al., 2014).

In the 18th century the turnip and the oilseed-producing morphotypes were described as two different species by Linnaeus who named them B. rapa and B. campestris (PROTA, 2018). Metzger united the two species under B. rapa (Flora of China, 2018). Of the synonyms listed for B. rapa in The Plant List (2013), B. amplexicaulis, B. japonica, B. musifolia, B. polymorpha and Raphanus chinensis are illegitimate names; B. lutea is an invalid name and Sinapis communis and S. glauca are unresolved names.

The following description is from PROTA (2018):

Erect, annual to biennial herb up to 1.5 m tall, with stout taproot, sometimes partly swollen (turnip); stem branched. Leaves arranged spirally but in a basal rosette during the vegetative stage; stipules absent; lower leaves more or less petiolate, pinnately parted with 1-5 pairs of small lateral lobes and large terminal lobe up to 90 cm × 35 cm, crenate, toothed, sinuate or entire, usually hairy; stem leaves pinnately parted to simple, clasping at base, glabrous, glaucous. Inflorescence a terminal umbel-like raceme up to 60 cm long, with open flowers overtopping the buds, elongating in fruit. Flowers bisexual, regular, 4-merous; pedicel up to 3 cm long, ascending; sepals 5-8 mm long, spreading, yellow-green; petals obovate, 0.5-1 cm long, clawed, bright yellow; stamens 6; ovary superior, cylindrical, 2-celled, stigma globose. Fruit a linear silique 4-10 cm × 2-4 mm, with a tapering beak 0.5-3 cm long, dehiscent, up to 30-seeded. Seeds globose, 1-1.5 mm in diameter, finely reticulate, dark brown. Seedling with epigeal germination, with a taproot and lateral roots; hypocotyl c. 5 cm long, epicotyl 2-4 mm long; cotyledons with petiole c. 2 cm long, blade cordate, 1-1.5 cm long, cuneate at base, notched at apex.

The long history of B. rapa cultivation, the discrepancies about its native distribution and the great variety of cultivars known make it difficult to provide a clear history of its introduction and spread (PROTA, 2018). It is likely the domestication of B. rapa occurred following the advent of written history (approximately 3,500 BCE). Demographic modelling suggests a series of domestication events occurring in B. rapa between 2400 and 4100 years ago, starting in Europe and Central Asia and continuing east, which is validated by written records from the region (Qi et al., 2017). There are references to ‘oilseed rape’ and ‘mustard’ in Indian Sanskrit writings of 2000 to 1500 BCE, and in Greek, Roman and Chinese writings of 500 to 200 BCE (Canadian Food Inspection Agency, 2018). B. rapa is also mentioned as occurring during the empire of Alexander the Great (356-323 BCE); from where the species is believed to have spread to South-East Asia and Africa via trade routes (PROTA, 2018). Dixon (2006) suggests that B. rapa originated in the Mediterranean; spreading to into Europe, northwards to Scandinavia, eastwards to Germany, and eventually towards Asia. He also suggests that the species reached China via Mongolia and was introduced to Japan via either China or Siberia. In Europe commercial plantings of rapeseed are recorded in the Netherlands as early as the 16th century (Canadian Food Inspection Agency, 2018). The species is known from the New World since the 1800s (New York Botanical Garden, 2018).

Soil drainage

• free

Soil reaction

• acid
• alkaline
• neutral

Soil texture

• heavy
• light
• medium

Special soil tolerances

• infertile

Natural Dispersal

The species is reported as being dispersed by autochory (self-dispersal) and anemochory (wind dispersal; India Biodiversity Portal, 2018). Seeds may also be dispersed by water in areas where plants grow along river margins.

Vector Transmission (Biotic)

Brassica rapa is reported as being dispersed by birds and other animals, although no further details are given (Vibrans, 2018; India Biodiversity Portal, 2018).

Accidental Introduction

Brassica rapa has been reported as an escape from cultivation and as growing as a volunteer in crop fields (Young-Mathews, 2012).

Intentional Introduction

Brassica rapa has a long history of cultivation and has been distributed worldwide as a crop (PROTA, 2018).

Brassica rapa is a weed in cultivated sites, which can lead to a reduction in crop yield (Vibrans, 2018).

Impact on Habitats

The seeds of B. rapa can survive in the soil for fifty years or more when deeply buried; seeds closer to the soil surface are not as persistent (Young-Mathews, 2012). The species may become a fire hazard when dry at the end of the growing season (Young-Mathews, 2012).  

Brassica rapa is considered a coloniser of disturbed habitats and a volunteer weed in cultivated land in Canada, possibly outcompeting other species (Canadian Food Inspection Agency, 2018). Despite B. rapa being a frequent to occasional dominant species in disturbed and cultivated sites in Mexico, there is no evidence of negative effects in these habitats (Vibrans,2018). Its low stature does not promote the shading of other species and since most of its growth is during winter and during the rainy season, it avoids competition with other species.

Brassica rapa can hybridise with other Brassica spp., which could lead to gene flow into wild populations, including some from transgenic species (Warwick et al., 2008). Hybridisation between glyphosate-resistant B. napus and B. rapa was reported in Canada. Transgenic hybrids entering the wild might lead to an increase in fitness and invasiveness of B. rapa. More research is needed to understand the ecological implications of transgenic hybrids in natural populations.

Impact on Biodiversity

Roots, leaves and seeds of some B. rapa cultivars can contain high levels of erucic acid and glucosinolates that can irritate digestive tracts or create thyroid problems in animals, especially livestock, if consumed in large quantities (Young-Mathews, 2012). Toxicity symptoms include colic, diarrhoea, anorexia, excessive salivation and thyroid enlargement. Some cultivars have been developed that have lower levels of erucic acid and glucosinolates to make the oil and leaves safer for consumption.

Although no specific impacts over other species and the habitats are reported, disturbances will promote the spread of B. rapa, and it may form dense stands that displace other species (California Invasive Plant Council, 2018).

The oil contained in the seed of some cultivars of this species can be rich in erucic acid, which is toxic to animals. Some cultivars have been selected to have lower levels of erucic acid (Useful Tropical Plants, 2018).

• Proved invasive outside its native range
• Has a broad native range
• Highly adaptable to different environments
• Is a habitat generalist
• Pioneering in disturbed areas
• Tolerant of shade
• Fast growing
• Has high reproductive potential
• Has propagules that can remain viable for more than one year
• Has high genetic variability

• Negatively impacts agriculture
• Negatively impacts animal health
• Negatively impacts livelihoods
• Threat to/ loss of native species

• Competition - monopolizing resources
• Pest and disease transmission
• Hybridization
• Poisoning
• Rapid growth

• Highly likely to be transported internationally accidentally
• Highly likely to be transported internationally deliberately
• Difficult to identify/detect as a commodity contaminant
• Difficult/costly to control

Economic Value

Brassica rapa is one of the oldest Brassicaceae in cultivation (PROTA, 2018). The products of various cultivars are sold in markets worldwide; for example, turnips, Chinese cabbage and pakchoi. The fruits are sold at markets in Mexico as bird food (Vibrans, 2018).

The oils from B. rapa seeds are used as cooking oil, industrial lubricant, lamp oil, for soap making and for biodiesel production (Young-Mathews, 2012; Canadian Food Inspection Agency, 2018; Vibrans, 2018; PROTA, 2018). Since the Second World War, rapeseed oil production in Europe and Canada has increased. China, India, Europe and Canada are now the top producers, with potential for the crop to be successfully grown in USA, South America and Australia (Canadian Food Inspection Agency, 2018). Although much of commercial production of rapeseed oil used for cooking comes from B. napus (as Canola oil), some of the production still comes from B. rapa.

Social Benefit

Brassica rapa is widely cultivated for its roots, leaves, seed oil and as a fodder (PFAF, 2018). The flowers of some varieties are also consumed. The taproot (turnip), the leaves and flowers are used as a vegetable, boiled, fried, pickled or eaten raw as salads (PROTA, 2018). The species is especially popular in Europe and Asia. In Europe, some cultivars are important as fodder crop. Per 100 g edible portion, B. rapa leaves contain the following: 95 g water, 1.2 g protein, 0.2 g fat, 2.2 g carbohydrates, 0.5 g fibre, 49 mg Ca, 0.7 mg Fe, 0.9 mg vitamin A and 38 mg vitamin C. It is low in energy value, about 65 kJ/100 g (PROTA, 2018).

Although much of the rapeseed oil production now from B. napus, B. rapa is still also cultivated for its oil, mainly for human consumption and for lamp oil (PROTA, 2018; USDA-ARS, 2018).

Brassica rapa leaves, seeds and stems are used ethnobotanically for cancer treatments and in Chinese traditional medicine (India Biodiversity Portal, 2018). The seeds are used as a poultice for burns (PFAF, 2018). Leaf and root extracts of B. rapa have antibacterial and antifungal properties (India Biodiversity Portal, 2018; PROTA, 2018). Extracts of the plant are also used as insecticide against aphids, red spider mites and flies (PFAF, 2018).

Researchers at the University of Wisconsin-Madison (USA) have selectively bred a subspecies of B. rapa, known as Rapid Cycling Brassica rapa, which has an extremely short life cycle, to be used a model organism in education and plant studies (Wisconsin Fast Plants, 2018). This variety is quite small, easy to grow, produces flowers two weeks after planting, and has a rapid seed maturation with no seed dormancy (Daugherty and Musgrave, 1994). Research done using B. rapa include studies into plant physiology, reproduction, conservation, evolution, crop domestication and molecular and population genetics (Demchik and Day, 1996; Kleier et al., 1998, Wise et al., 2002; Cardoza and Stewart Jr, 2004; Lou et al., 2007; Waller et al., 2008; Mithila and Hall, 2013, Franks et al., 2016, Cheng et al., 2016).

Brassica rapa is also an important gene source for other Brassicaceae; for example, the species has provided genes for disease resistance for B. napus (USDA-ARS, 2018).

Environmental Services

Brassica rapa flowers attract bees and butterflies, who visit them for the pollen and nectar. Some insects, including beetles and butterflies are reported as feeding on Brassica species. The seeds are eaten by various birds and the foliage can be eaten in limited amounts by livestock and other herbivores (Encyclopedia of Life, 2018). The species is also reported as being used for soil improvement (USDA-ARS, 2018).

Brassica rapa is used as a winter annual or a rotational cover crop in vegetable, speciality crop and row crop production. It has the potential to prevent erosion, suppress weeds and pests, alleviate soil compaction, and scavenge nutrients. When used as a cover crop, plants should be eliminated before or at full bloom to avoid seed set and volunteers in subsequent crops. Cultivars with larger roots have been a popular forage crop for livestock in Europe and Asia for at least 600 years. Forage turnip is a useful crop for extending the fall grazing season for dairy cows and other livestock (Young-Mathews, 2012)