Cucumber

Cultivars and pollination

Most cucumber cultivars are seeded and require pollination. For this purpose, thousands of honey beehives are carried to cucumber fields each year just before bloom. Cucumbers can be pollinated by bumblebees and several other wild bee species. Most cucumbers that require pollination are self-incompatible, thus requiring the pollen of another plant in order to form seeds and fruit.^[7] Some self-compatible cultivars exist that are related to the 'Lemon cucumber' cultivar.^[7]

Some cultivars are parthenocarpic, creating seedless fruit without pollination; these are often grown in greenhouses. However, fruit set is significantly higher when bees visit the flowers.^[8]

Traditional cultivars produce male blossoms first, then female, in about equivalent numbers. Newer gynoecious hybrid cultivars produce almost all female blossoms. They may have a pollenizer cultivar interplanted, and the number of beehives per unit area is increased, but temperature changes induce male flowers even on these plants, which may be sufficient for pollination to occur.^[7]

• Example cultivars
• 
  Salad cucumber
• 
  An Indian yellow cucumber
• 
  Komkommer (Cucumis sativus 'Gele Tros')
• 
  A varietal grown by the Hmong people with textured skin and large seeds
• 
  Lemon cucumber

Herbivore defense

Phytochemicals in cucumbers may discourage natural foraging by herbivores, such as insects, nematodes or wildlife.^[9] As a possible defense mechanism, cucumbers produce cucurbitacin C,^[10] which causes a bitter taste in some cucumber varieties. This potential mechanism is under preliminary research to identify whether cucumbers are able to deter herbivores and environmental stresses by using an intrinsic chemical defense, particularly in the leaves, cotyledons, pedicel, carpopodium, and fruit.^[10][11]

Taxonomy and genetics

Cucumis sativus was described by Carl Linnaeus in 1753 in his Species Plantarum.^[12] As of October 2022^[update], Plants of the World Online accepted 61 species in the genus Cucumis, also created by Linnaeus.^[13]

C. sativus is the sole member of the genus to have 2N=14 chromosomes.^[14] In 2009, the cucumber genome was sequenced.^[15] A study of genetic recombination during meiosis provided a high resolution landscape of meiotic DNA double strand-breaks and genetic crossovers in the species.^[16]

Nutrition

Raw cucumber (with peel) is 95% water, 4% carbohydrates, 1% protein, and contains negligible fat (table). In a reference amount of 100 grams (3.5 oz), raw cucumber provides 16 calories of food energy, and has a low content of micronutrients notable only for vitamin K at 14% of the Daily Value (table).

Aroma and taste

Depending on variety, cucumbers may have a mild melon aroma and flavor, in part resulting from unsaturated aldehydes, such as (E,Z)-nona-2,6-dienal, and the cis- and trans- isomers of 2-nonenal.^[20] The slightly bitter taste of cucumber rind results from cucurbitacins.^[21] The polyphenol content is higher in unpeeled cucumbers.^[22]

Culinary uses

Wikibooks Cookbook has a recipe/module on

• Cucumber

In horticulture, cucumbers are classified into three main cultivar groups: slicing, pickling, and seedless/burpless. Cucumbers grown to eat fresh are called slicing cucumbers. The main varieties of slicers mature on vines with large leaves that provide shading.^[4][23] Slicers grown commercially for the North American market are generally longer, smoother, more uniform in color, and have much tougher skin. In contrast, those in other countries, often called European cucumbers, are smaller and have thinner, more delicate skin, often with fewer seeds, thus are often sold in plastic skin for protection. This variety is called a 'telegraph cucumber' in Australasia.^[24]

Pickling with brine, sugar, vinegar, and spices creates flavored products from cucumbers and other foods.^[25] Cucumbers grown for pickling are shorter, thicker, and thinner-skinned than other varieties.^[26] Gherkins, cornichons,^[27] or baby pickles, are small cucumbers, typically those 2.5 to 12.5 centimetres (1 to 5 in) in length, often with bumpy skin, which are typically used for pickling.^[28][29][30] The word gherkin comes from the early modern Dutch gurken or augurken ('small pickled cucumber').^[31] The term is used in the name for Cucumis anguria, the West Indian gherkin, a closely related species.^[32]

Burpless cucumbers are sweeter and have a thinner skin than other varieties of cucumber. They are reputed to be easy to digest and to have a pleasant taste. They can grow as long as 60 centimeters (2 ft), are nearly seedless, and have a delicate skin. Most commonly grown in greenhouses, these parthenocarpic cucumbers are often found in grocery markets, shrink-wrapped in plastic. They are marketed as either burpless or seedless, as the seeds and skin of other varieties of cucumbers are said to give some people gas.^[33]

Cucumber shoots are regularly consumed as a vegetable, especially in rural areas. In Thailand they are often served with a crab meat sauce. They can be stir fried or used in soups.^[34]

• 
  Japanese asazuke pickled cucumbers sold as street food on Enoshima island
• 
  A Scandinavian cucumber in slices
• 
  Grated cucumber
• 
  As a side dish with yoghurt, raita or mizeria
• 
  Pickling cucumbers
• 
  Gherkins

Roman Empire

According to Pliny the Elder, the Emperor Tiberius had the cucumber on his table daily during summer and winter. In order to have it available for his table every day of the year, the Romans reportedly used artificial growing methods (similar to the greenhouse system) using mirrorstone, Pliny's lapis specularis, believed to have been sheet mica: "Indeed, he was never without [cucumbers]; for he had raised beds made in frames upon wheels, by means of which the cucumbers were moved and exposed to the full heat of the sun; while, in winter, they were withdrawn, and placed under the protection of frames glazed with mirrorstone."^[44][45] They were cultivated in specularia, cucumber houses glazed with oiled cloth.^[44] Pliny describes the vegetable as very small, probably like a gherkin. Separately, he describes the preparation of a medication known as elaterium, but this may have been Ecballium elaterium, known in pre-Linnean times as Cucumis silvestris or Cucumis asininus ('wild cucumber' or 'donkey cucumber'), a different species.^[46] Pliny writes about several other varieties of cucumber, including the cultivated cucumber,^[47] and remedies from the different types (9 from the cultivated; 5 from the "anguine;" and 26 from the "wild").^{[citation needed]}

Middle Ages

Charlemagne had cucumbers grown in his gardens in the 8th/9th century. They were reportedly introduced into England in the early 14th century, lost, then reintroduced approximately 250 years later. The Spaniards (through the Italian Christopher Columbus) brought cucumbers to Haiti in 1494. In 1535, Jacques Cartier, a French explorer, found "very great cucumbers" grown on the site of what is now Montreal.^[48]

Early-modern era

Throughout the 16th century, European trappers, traders, bison hunters, and explorers bartered for the products of American Indian agriculture. The tribes of the Great Plains and the Rocky Mountains learned from the Spanish how to grow European crops. The farmers on the Great Plains included the Mandan and Abenaki. They obtained cucumbers and watermelons from the Spanish, and added them to the crops they were already growing, including several varieties of corn and beans, pumpkins, squash, and gourd plants.^[49] The Iroquois were growing them when the first Europeans visited them.^[50] In 1630, the Reverend Francis Higginson wrote in his book New-Englands Plantation that "The countrie aboundeth naturally with store of roots of great varietie and good to eat. Our turnips, parsnips, and carrots are here both bigger and sweeter than is ordinary to be found in England. Here are store of pompions, cowcumbers, and other things of that nature which I know not".^[51] In New England Prospect (1633, England), William Wood wrote that "The ground affords very good kitchin gardens, for Turneps, Parsnips, Carrots, Radishes, and Pompions, Muskmillons, Isquoter-squashes, coucumbars, Onyons, and whatever grows well in England grows as well there, many things being better and larger."^[52]

Age of Enlightenment

Samuel Pepys wrote in his diary on 22 August 1663 that "this day Sir W. Batten tells me that Mr. Newburne is dead of eating cowcumbers, of which the other day I heard of another, I think.^[53] John Evelyn in 1699 wrote that the cucumber, "however dress'd, was thought fit to be thrown away, being accounted little better than poyson".^[54][55] According to the 18th-century British lexicographer and wit Samuel Johnson, it was commonly said among English physicians that a cucumber "should be well sliced, and dressed with pepper and vinegar, and then thrown out, as good for nothing."^[56]