Parsnip

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Parsnip
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Apiales
Family: Apiaceae
Genus: Pastinaca
Species: P. sativa
Binomial name
Pastinaca sativa
L.[1]
Pastinaca sativa fruits and seeds

The parsnip (Pastinaca sativa) is a root vegetable closely related to the carrot and parsley. It is a biennial plant usually grown as an annual. Its long tuberous root has cream-colored skin and flesh and can be left in the ground when mature as it becomes sweeter in flavor after winter frosts. In its first growing season, the plant has a rosette of pinnate, mid-green leaves. If unharvested, it produces its flowering stem, topped by an umbel of small yellow flowers, in its second growing season. By this time the stem is woody and the tuber inedible. The seeds are pale brown, flat and winged.

The parsnip is native to Eurasia. It has been used as a vegetable since antiquity and was cultivated by the Romans, although there is some confusion in the literature of the time between parsnips and carrots. It was used as a sweetener before the arrival in Europe of cane sugar. It was introduced into the United States in the nineteenth century.

The parsnip is usually cooked but can also be eaten raw. It is high in vitamins and minerals, especially potassium. It also contains antioxidants and both soluble and insoluble dietary fiber. It can be cultivated in deep, stone-free soils and is attacked by the carrot fly and other insect pests, viruses and fungal diseases, of which canker is the most serious. In sunlight, handling the stems and foliage can cause a skin rash.

Description[edit]

Parsnips are grown for their fleshy, edible cream-colored taproots. The roots are generally smooth, although lateral roots sometimes form. Most are cylindrical, but some cultivars have a more bulbous shape, which generally tend to be favored by food processors as they are more resistant to breakage. The plant has a apical meristem that produces a rosette of pinnate leaves, each with several pairs of leaflets with toothed margins. The lower leaves have short stems, the upper ones are stemless, and the terminal leaves have three lobes. The highly branched floral stem is hollow and grooved, and can grow to more than 150 cm (60 in) tall.[2]

Parsnip is a biennial with a rosette of roughly hairy leaves that has a pungent odor when crushed. The petioles are grooved and have sheathed bases. The leaves are once- or twice-pinnate with broad, ovate, sometimes lobed leaflets with toothed margins; they grow up to 40 cm (16 in) long. The flower stalk develops in the second year, growing to a height of 40 to 200 cm (20 to 80 in). It is hairy, grooved, hollow (except at the nodes), and sparsely branched. It has a few stalkless, single-lobed leaves measuring 5 to 10 cm (2 to 4 in) long that are arranged in opposite pairs. The yellow flowers are in a loose, compound umbel measuring 10 to 20 cm (4 to 8 in) in diameter. There are 6–25 straight pedicels, each measuring 2–5 cm (1–2 in) that support the umbellets (secondary umbels). The umbels and umbellets usually have no upper or lower bracts. The flowers have tiny sepals or lack them entirely, and measure about 3.5 mm. They consist of five yellow petals that are curled inward, five stamens, and one pistil. The fruits, or schizocarps, are oval and flat, with narrow wings and short, spreading styles. They are colored straw to light brown, and measure 4–8 mm long.[3]

Despite the slight morphological differences between the two, wild parsnip is the same taxon as the cultivated version, and the two will readily cross-pollinate.[3] Parsnip has a chromosome number of 2n=22.[4]

History[edit]

Like carrots, parsnips are native to Eurasia and have been eaten there since ancient times. Zohary and Hopf note that the archaeological evidence for the cultivation of the parsnip is "still rather limited", and that Greek and Roman literary sources are a major source about its early use. They warn that "there are some difficulties in distinguishing between parsnip and carrot (which, in Roman times, were white or purple) in classical writings since both vegetables seem to have been sometimes called pastinaca yet each vegetable appears to be well under cultivation in Roman times".[5] The parsnip was much esteemed and the Emperor Tiberius accepted part of the tribute payable to Rome by Germany in the form of parsnips. In Europe, the vegetable was used as a source of sugar before sugar cane and beet were available.[6] As pastinache comuni, the "common" pastinaca figures in the long list of comestibles enjoyed by the Milanese given by Bonvesin de la Riva in his "Marvels of Milan" (1288).[7] This plant was introduced to North America simultaneously by the French colonists in Canada and the British in the Thirteen Colonies for use as a root vegetable, but in the mid-nineteenth century it was replaced as the main source of starch by the potato and consequently was less widely cultivated.[8][9]

In 1859, a new cultivar called "Student" was developed by James Buckman at the Royal Agricultural College in England. He back-crossed cultivated plants to wild stock, aiming to demonstrate how native plants could be improved by selective breeding. This experiment was so successful that the Student became the major variety in cultivation in the late nineteenth century.[10]

Taxonomy[edit]

Illustration from Johann Georg Sturm's 1796 Deutschlands Flora in Abbildungen

The parsnip was first officially described by Carolus Linnaeus in his 1753 work Species Plantarum.[11] It has acquired several synonyms in its taxonomic history:[12]

Like most plants of agricultural importance, several subspecies and varieties of P. sativa have been described, but these are mostly no longer recognized as independent taxa,[12] but rather, morphological variations of the same taxon.[3]

  • subsp. divaricata (Desf.) Rouy & Camus
  • subsp. pratensis (Pers.) Čelak.
  • subsp. sylvestris (Mill.) Rouy & Camus
  • subsp. umbrosa (Steven, ex DC.) Bondar. ex O.N.Korovina
  • subsp. urens (Req. ex Godr.) Čelak.
  • var. brevis Alef.
  • var. edulis DC.
  • var. hortensis Ehrh. ex Hoffm.
  • var. longa Alef.
  • var. pratensis Pers.
  • var. siamensis Roem. & Schult. ex Alef.

In Eurasia, some authorities distinguish between cultivated and wild versions of parsnip by using subspecies sylvestris for the latter, or even elevating it to species status as Pastinaca sylvestris. In Europe, various subspecies have been named based on characteristics such as the hairiness of the leaves, the extent to which the stems are angled or rounded, and the size and shape of the terminal umbel.[3]

The etymology of the genus name Pastinaca is not known with certainty, but is probably derived from either the Latin word pastino, meaning "to prepare the ground for planting of the vine" or pastus, meaning "food". The specific epithet sativa means "sown".[13]

Uses[edit]

Parsnips resemble carrots and can be used in similar ways but they have a sweeter taste, especially when cooked.[14] While parsnips can be eaten raw, they are more commonly served cooked. They can be baked, boiled, pureed, roasted, fried or steamed. When used in stews, soups and casseroles they give a rich flavor.[6] In some cases, the parsnip is boiled and the solid portions are removed from the soup or stew, leaving behind a more subtle flavor than the whole root, and starch to thicken the dish. Roast parsnip is considered an essential part of Christmas dinner in some parts of the English-speaking world and frequently features in the traditional Sunday Roast. [15] Parsnips can also be fried or thinly sliced and made into crisps. Parsnips can be made into a wine that has a taste similar to Madeira.[16]

In Roman times, parsnips were believed to be an aphrodisiac.[17] However, parsnips do not typically feature in modern Italian cooking. Instead, they are fed to pigs, particularly those bred to make Parma ham.[18]

Nutritional properties[edit]

Parsnip, raw
Nutritional value per 100 g (3.5 oz)
Energy 314 kJ (75 kcal)
Carbohydrates 18 g
- Sugars 4.8
- Dietary fiber 4.9 g
Fat 0.3 g
Protein 1.2 g
Water 79.53 g
Thiamine (vit. B1) 0.09 mg (8%)
Riboflavin (vit. B2) 0.05 mg (4%)
Niacin (vit. B3) 0.7 mg (5%)
Pantothenic acid (B5) 0.6 mg (12%)
Vitamin B6 0.09 mg (7%)
Folate (vit. B9) 67 μg (17%)
Vitamin C 17 mg (20%)
Vitamin E 1.49 mg (10%)
Vitamin K 22.5 μg (21%)
Calcium 36 mg (4%)
Iron 0.59 mg (5%)
Magnesium 29 mg (8%)
Manganese 0.56 mg (27%)
Phosphorus 71 mg (10%)
Potassium 375 mg (8%)
Sodium 10 mg (1%)
Zinc 0.59 mg (6%)
Link to USDA Database entry
Percentages are roughly approximated
using US recommendations for adults.
Source: USDA Nutrient Database

A typical 100 g parsnip contains 75 Calories (230 kJ) of energy. Most parsnip cultivars consist of about 80% water, 5% sugar, 1% protein, 0.3% fat and 5% dietary fiber. The parsnip is rich in vitamins and minerals and is particularly rich in potassium with 375 mg per 100 g.[19] Several of the B-group vitamins are present but most of the vitamin C is lost in cooking. Since most of the vitamins and minerals are found close to the skin many will be lost unless the root is finely peeled or cooked whole. During frosty weather, part of the starch is converted to sugar and the root tastes sweeter.[20]

The consumption of parsnips has potential health benefits. They contain anti-oxidants such as falcarinol, falcarindiol, panaxydiol and methyl-falcarindiol which have anti-cancer, anti-inflammatory and anti-fungal properties. The dietary fiber in parsnips is partly of the soluble and partly the insoluble type and comprises cellulose, hemicellulose and lignin. The high fiber content of parsnips may help prevent constipation and reduce blood cholesterol levels.[21]

Etymology[edit]

While folk etymology sometimes assumes the name is a portmanteau of parsley and turnip, it actually comes from Middle English pasnepe, alteration (influenced by nep, turnip) of Old French pasnaie (now panais) from Latin pastinum, a kind of fork, whose ending was changed to -nip by analogy with turnip because it was mistakenly assumed to be a kind of turnip.[22]

Cultivation[edit]

The wild parsnip from which the modern cultivated varieties were derived is a plant of dry rough grassland and waste places, particularly on chalk and limestone.[23] Parsnips are biennials but are normally grown as annuals. Sandy and loamy soils are preferable to silt, clay and stony ground as the latter produce short, forked roots.. Parsnip seed significantly deteriorates in viability if stored for long. Seeds are usually planted in early spring, as soon as the ground can be worked to a fine tilth, in the position where the plants are to grow. The growing plants are thinned and kept weed free. Harvesting begins in late fall after the first frost, and continues through winter. The rows can be covered with straw to enable the crop to be lifted during frosty weather.[24] Low soil temperatures cause some of the starches stored in the roots to be converted into sugars, giving them a sweeter taste.[25]

Cultivation problems[edit]

Parsnip leaves are sometimes tunnelled by the larvae of the celery leaf miner (Euleia heraclei). Irregular pale brown passages can be seen meandering between the upper and lower surfaces of the leaves. The effects are most serious on young plants as whole leaves may shrivel and die. Treatment is by removing affected leaflets or whole leaves, or by chemical means.[24]

The crop can be attacked by larvae of the carrot fly (Chamaepsila rosae). This pest feeds on the outer layers of the root, burrowing its way inside later in the season. Seedlings may be killed while larger roots are rendered useless. The damage done provides a point of entry for fungal rots and canker. The fly is attracted by the smell of bruised tissue and damage can be minimized by sowing thinly, providing good growing conditions, avoiding thinning the plants and weeding carefully.[26] Parsnip is used as a food plant by the larvae of some Lepidopteran species including the parsnip swallowtail, the common swift moth, the garden dart moth and the ghost moth.[27] The larvae of the parsnip moth (Depressaria radiella), native to Europe and accidentally introduced to North America in the mid-1800s, construct their webs on the umbels, feeding on flowers and developing seeds.[28]

Parsnip canker is a serious disease of this crop. Black or orange-brown patches occur around the crown and shoulders of the root accompanied by cracking and hardening of the flesh. It is more likely to occur when seed is sown into cold, wet soil, the pH of the soil is too low or the roots have already been damaged by carrot fly larvae. Better results may be obtained by choosing a resistant variety and sowing later in the season, producing smaller, more closely spaced plants.[29] Several fungi are associated with canker, including Phoma complanata, Ilyonectria radicicola, Itersonilia pastinaceae, and I. perplexans. In Europe, Centrospora acerina has been found to cause a black rot that kills the plant early.[30] Watery soft rot, caused by Sclerotinia minor and S. sclerotiorum, causes the taproot to become soft and watery. A white or buff-colored mold grows on the surface. The pathogen is most common in temperate and subtropical regions that have a cool wet season.[31]

Violet root rot caused by the fungus Helicobasidium purpureum sometimes affects the roots, covering them with a purplish mat to which soil particles adhere. The leaves become distorted and discolored and the mycelium can spread through the soil between plants. Some weeds can harbour this fungus and it is more prevalent in wet, acid conditions. Affected plants should be removed and burnt and susceptible crops should not be grown in the area for four years.[24] Erysiphe heraclei causes a powdery mildew that can cause significant crop loss. Infestation by this causes results in yellowing of the leaf and loss of foliage. Moderate temperatures and high humidity favor the development of the disease.[32]

Several viruses are known to infect the plant, including seed-borne strawberry latent ringspot virus, parsnip yellow fleck virus, parsnip leafcurl virus, parsnip mosaic potyvirus, and potyvirus celery mosaic virus. The latter causes clearing or yellowing of those areas of the leaf immediately aligning the veins, the appearance of ochre mosaic spots, and leaf crinkling in infected plants.[33]

Dangers[edit]

While the root of the parsnip is edible, handling the shoots and leaves of the plant requires caution as the sap is toxic.[34] Like many other members of the family Apiaceae, the parsnip contains furanocoumarin, a photosensitive chemical that causes a condition known as phytophotodermatitis.[34] The condition is a type of chemical burn rather than an allergic reaction, and is similar to the rash caused by poison ivy. Symptoms include redness, burning, and blisters. Afflicted areas can remain discolored for up to two years.[35] Although there have been some reports of gardeners experiencing toxic symptoms after coming into contact with foliage,[36] these have been small in number compared to the number of people that grow the crop. The problem is most likely to occur on a sunny day when gathering foliage or pulling up old plants that have gone to seed. The symptoms have mostly been mild to moderate.[37] The toxic properties of parsnip extracts are resistant to heating, or a storage period of several months. Toxic symptoms can also affect livestock and poultry in parts of their bodies where their skin is exposed.[38]

Polyacetylenes can be found in Apiaceae vegetables like parsnip, and they show cytotoxic activities.[39]

References[edit]

  1. ^ "Pastinaca sativa information from NPGS/GRIN". www.ars-grin.gov. Retrieved 2008-03-02. 
  2. ^ Rubatsky et al. (1999), pp. 30–31.
  3. ^ a b c d Cain et al. (2010), p. 218.
  4. ^ Kalloo G. (1993). "34 – Parsnip: Pastinaca sativa L.". In Kaloo, G; Bergh, B.O. (eds). Genetic Improvement of Vegetable Crops. Permagon. pp. 485–486. doi:10.1016/B978-0-08-040826-2.50038-2. ISBN 978-0080408262. 
  5. ^ Zohary, Daniel; Hopf, Maria (2000). Domestication of Plants in the Old World (3rd ed.). Oxford: University Press. p. 203. 
  6. ^ a b "The Parsnip". Towne's Harvest Garden. Montana State University. Retrieved 2013-03-30. 
  7. ^ Noted by John Dickie, Delizia! The Epic History of Italians and Their Food (New York, 2008), p. 38 (where they are identified as parsnips).
  8. ^ McNeill, William H (1999). "How the Potato Changed the World's History". Social Research 66 (1): 67–83. JSTOR 40971302. 
  9. ^ Cain et al, p. 224
  10. ^ Stocks, Christopher (2009). Forgotten Fruits: The Stories Behind Britain's Traditional Fruit and Vegetables. Random House. p. 133. ISBN 978-1-4090-6197-7. 
  11. ^ Linnaeus, Carolus (1753). Species Plantarum (in Latin) 1. Stockholm: Laurentii Salvii. p. 262. 
  12. ^ a b Kays, Stanley J. (2011). "3. Latin binomials and synonyms". Cultivated Vegetables of the World: A Multilingual Onomasticon. Wageningen Academic Publishers. pp. 617–708. ISBN 978-90-8686-720-2. 
  13. ^ Averill, Kristine M.; Di'Tommaso, Antonio. "Wild parsnip (Pastinaca sativa): A troublesome species of increasing concern". Weed Technology 21: 279–281. doi:10.1614/WT-05-186.1. 
  14. ^ Alleman, Gayle Povis; Webb, Denise and Smith, Susan Male. "Parsnips: Natural Weight-Loss Foods". Discovery Health. Publications International. Retrieved 10 March 2011. 
  15. ^ Oliver,Jamie. "Christmas vegetables". JamieOliver.com. Retrieved 2013-03-30. 
  16. ^ Hopkins, Len (2012). Making Wine with Fruits, Roots & Flowers: Recipes for Distinctive & Delicious Wild Wines. Krause Publications. p. 162. ISBN 978-1-4403-2034-7. 
  17. ^ Phillips, Henry (1831). The Companion for the Kitchen Garden. H. Colburn and R. Bentley. p. 42. "Dioches, Cleophantus, Philistio, and Orpheus, as well as Pliny, all wrote on the aphrodisiac quality of the parsnip." 
  18. ^ Eat the seasons. "Eat parsnips". 
  19. ^ "Nutrient data for 11298, Parsnips, raw". Nutrient Data Laboratory. USDA. Retrieved 30 Mar 2013. 
  20. ^ Hamilton, Dave; Hamilton, Andy. "Parsnips Pastinaca sativa". Selfsufficientish. Retrieved 2013-04-02. 
  21. ^ Siddiqui, I. R. (1989). "Studies on vegetables: fiber content and chemical composition of ethanol-insoluble and -soluble residues". Journal of Agricultural and Food Chemistry 37 (3): 647–650. doi:10.1021/jf00087a015. 
  22. ^ "Historical Jottings on Vegetables: The Celery and the Parsnip". Journal of Horticulture and Practical Gardening 8: 282. 1884. 
  23. ^ McKlintock, David; Fitter, R.S.R. (1956). The Pocket Guide to Wild Flowers. Collins. p. 102. 
  24. ^ a b c Brickell, Christopher (ed) (1992). The Royal Horticultural Society Encyclopedia of Gardening. Dorling Kindersley. pp. 356, 565. ISBN 9780863189791. 
  25. ^ Rubatsky et al. (1999), p. 225.
  26. ^ "Carrot fly". Garden Organic. Henry Doubleday Research Association. Retrieved 2013-03-29. 
  27. ^ "Robinson, G.S.; Ackery, P.R.; Kitching, I.J.; Beccaloni, G.W.; Hernández, L.M.". A Database of the World's Lepidopteran Hostplants. Natural History Museum, London. 2010. 
  28. ^ Cain et al. (2010), p. 232.
  29. ^ "How to deal with parsnip canker". Pests and diseases. Which? Gardening factsheet. 2012-08-01. Retrieved 2013-03-29. 
  30. ^ Cains et al., pp. 232–233.
  31. ^ Snowdon, Anna L. (2010). Post-Harvest Diseases and Disorders of Fruits and Vegetables: Volume 2: Vegetables. Manson Publishing. p. 290. ISBN 978-1-84076-598-4. 
  32. ^ Koike, Steven T.; Gladders, Peter; Paulus, Albert O. (2007). Vegetable Diseases: A Color Handbook. Gulf Professional Publishing. p. 118. ISBN 978-0-12-373675-8. 
  33. ^ Cain et al. (2010), p. 233.
  34. ^ a b "Wild Parsnip (Pastinaca sativa)". Minnesota Department of Natural Resources. Retrieved 2013-03-29. 
  35. ^ Brenneman, William L. (2010). 50 Wild Plants Everyone Should Know. AuthorHouse. p. 38. ISBN 978-1-4520-4637-2. 
  36. ^ "Parsnips gave me blisters! Gardener covered in sores after brushing against vegetable leaves". Mail Online. 2010-08-27. Retrieved 2013-03-31. 
  37. ^ Robertson, John. "Pastinaca sativa, parsnip". The Poison Garden Website. Retrieved 2013-03-29. 
  38. ^ Cain et al. (2010), pp. 221–2.
  39. ^ Zidorn, Christian; Jöhrer, Karin; Ganzera, Markus; Schubert, Birthe; Sigmund, Elisabeth Maria; Mader, Judith; Greil, Richard; Ellmerer, Ernst P.; Stuppner, Hermann (2005). "Polyacetylenes from the Apiaceae vegetables carrot, celery, fennel, parsley, and parsnip and their cytotoxic activities". Journal of Agricultural and Food Chemistry 53 (7): 2518–2523. doi:10.1021/jf048041s. PMID 15796588. 

Cited literature[edit]

External links[edit]

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