Design of generalized search interfaces for health informatics

Strawberry Fragaria × ananassa
Strawberry fruit
Halved strawberry
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Rosales
Family:	Rosaceae
Genus:	Fragaria
Species:	F. × ananassa
Binomial name
Fragaria × ananassa Duchesne

The garden strawberry (or simply strawberry; Fragaria × ananassa)^[1] is a widely grown hybrid species of the genus Fragaria in the rose family, Rosaceae, collectively known as the strawberries, which are cultivated worldwide for their fruit. This is appreciated for its aroma, bright red color, juicy texture, and sweetness. It is eaten either fresh or in prepared foods such as jam, juice, pies, ice cream, milkshakes, and chocolates. Artificial strawberry flavorings and aromas are widely used in commercial products. Botanically, the strawberry is not a berry but an aggregate accessory fruit; each apparent 'seed' on the outside of the strawberry is actually an achene, a botanical fruit with a seed inside it.

The garden strawberry was first bred in Brittany, France, in the 1750s via a cross of F. virginiana from eastern North America and F. chiloensis, which was brought from Chile by Amédée-François Frézier in 1714. Cultivars of F. × ananassa have replaced the woodland strawberry F. vesca in commercial production. In 2022, world production of strawberries exceeded nine million tons, led by China with 35% of the total.

Strawberries have appeared in literature and art from Roman times; Virgil wrote about the snake lurking beneath the strawberry, an image reinterpreted by later writers including Shakespeare. Strawberries appear in Italian, Flemish, and German paintings, including Hieronymus Bosch's The Garden of Earthly Delights. It has been understood to symbolize the ephemerality of earthly joys, or the benefit that blessed souls get from religion, or to allegorize death and resurrection; by the late 20th century, it had come to symbolize female sexuality.

In Europe, until the 17th century cultivated plants were obtained by transplanting strawberries from the forests; the plants were propagated asexually by cutting off the runners.^[2]

F. virginiana, the Virginia strawberry, was brought to Europe from eastern North America; F. chiloensis, the Chilean strawberry, was brought from Chile by Amédée-François Frézier in 1714; it had been cultivated by Mapuche and Huilliche Indians.^[4]

At first introduction to Europe, the Virginia and Chilean strawberry plants grew vigorously, but produced no fruit. French gardeners in Brest and Cherbourg around the mid-18th century first noticed that when F. moschata and F. virginiana were planted in between rows of F. chiloensis, the Chilean strawberry bore abundant fruits. Soon afterwards, Antoine Nicolas Duchesne began to study the breeding of strawberries. He discovered that the female F. chiloensis plants could only be pollinated by male F. moschata or F. virginiana plants.^[3] In 1766, Duchesne determined F. ananassa to be a hybrid of F. chiloensis and F. virginiana. F. ananassa, which produces large fruits, is so named because it resembles the pineapple in smell, taste and berry shape.^[3]

In England, many varieties of F. ananassa were produced, and they form the basis of modern varieties of strawberries. Further breeding in Europe and America produced varieties with improved hardiness, disease resistance, size, and taste.^[3] During the Green Revolution of the 1950s, agronomists used selective breeding to expand phenotypic diversity of the garden strawberry. Adoption of perpetual flowering hybrids not sensitive to changes in photoperiod gave higher yields and enabled production in California to expand.^[5]

The phylogeny of the cultivated strawberry within the genus Fragaria of the Rosaceae family was determined by chloroplast genomics in 2021. The polyploidy (number of sets of chromosomes) is shown as "2N" etc by each species.^[6]

In culinary terms, a strawberry is an edible fruit. From a botanical point of view, it is not a berry but an aggregate accessory fruit, because the fleshy part is derived not from the plant's ovaries but from the receptacle that holds the ovaries.^[7] Each apparent 'seed"' on the outside of the strawberry is actually an achene, a botanical fruit with a seed inside it.^[7]

• 
  Leaves
• 
  Flower
• 
  Achenes (botanical fruits)
• Growth (video)

Nutrition

Nutritional value per 100 g (3.5 oz)
Energy	136 kJ (33 kcal)
Carbohydrates	7.68 g
Sugars	4.89 g
Dietary fiber	2 g
Fat	0.3 g
Protein	0.67 g
Vitamins and minerals Vitamins Quantity %DV† Thiamine (B1) 2% 0.024 mg Riboflavin (B2) 2% 0.022 mg Niacin (B3) 2% 0.386 mg Pantothenic acid (B5) 3% 0.125 mg Vitamin B6 3% 0.047 mg Folate (B9) 6% 24 μg Choline 1% 5.7 mg Vitamin C 65% 58.8 mg Vitamin E 2% 0.29 mg Vitamin K 2% 2.2 μg Minerals Quantity %DV† Calcium 1% 16 mg Iron 2% 0.41 mg Magnesium 3% 13 mg Manganese 17% 0.386 mg Phosphorus 2% 24 mg Potassium 5% 154 mg Sodium 0% 1 mg Zinc 1% 0.14 mg
Other constituents	Quantity
Water	90.95 g
Link to USDA Database entry
†Percentages estimated using US recommendations for adults,[8] except for potassium, which is estimated based on expert recommendation from the National Academies.[9]

Raw strawberries are 91% water, 8% carbohydrates, 1% protein, and contain negligible fat (table). A reference amount of 100 grams (3.5 oz) supplies 33 kilocalories, is a rich source of vitamin C (65% of the Daily Value, DV), and a good source of manganese (17% DV), with no other micronutrients in significant content (table). Strawberries contain a modest amount of essential unsaturated fatty acids in the achene (seed) oil.^[10]

Garden strawberries contain diverse phytochemicals, including the dimeric ellagitannin agrimoniin, which is an isomer of sanguiin H-6.^[11][12] Other polyphenols present include flavonoids, such as anthocyanins, flavanols, flavonols and phenolic acids, such as hydroxybenzoic acid and hydroxycinnamic acid.^[10] Although achenes comprise only about 1% of the total fresh weight of a strawberry, they contribute 11% of all polyphenols in the whole fruit; achene phytochemicals include ellagic acid, ellagic acid glycosides, and ellagitannins.^[13]

Pelargonidin-3-glucoside is the major anthocyanin in strawberries, with cyanidin-3-glucoside found in smaller amounts.^[14] Strawberries also contain purple minor pigments, such as dimeric anthocyanins.^[14]

Sweetness, fragrance and complex flavor are favorable attributes of strawberries.^[15] In plant breeding and farming, emphasis is placed on sugars, acids, and volatile compounds, which improve the taste and fragrance of ripe strawberries.^[16] Esters, terpenes, and furans are the chemical compounds having the strongest relationships to strawberry flavor, sweetness and fragrance, with a total of 31 out of some 360 volatile compounds significantly correlated to favorable flavor and fragrance.^[16][17][18] In breeding strawberries for the commercial market in the United States, the volatile compounds – methyl anthranilate and gamma-decalactone prominent in aromatic wild strawberries – are especially desired for their "sweet and fruity" aroma characteristics.^[17][18] As strawberry flavor and fragrance are characteristics that may appeal to consumers,^[17][18][19] they are used widely in manufacturing, including foods, beverages, confections, perfumes and cosmetics.^[20][21]

Modern strawberries are octoploid (8 sets of 7 chromosomes).^[22] The genome sequence of the garden strawberry was published in 2019.^[23]

Some people experience an anaphylactoid reaction to eating strawberries.^[24] The most common form of this reaction is oral allergy syndrome, but symptoms may also mimic hay fever or include dermatitis or hives, and, in severe cases, may cause breathing problems.^[25]

Proteomic studies indicate that the allergen may be tied to a protein for the red anthocyanin biosynthesis expressed in strawberry ripening, named Fra a1 (Fragaria allergen1).^[26] Homologous proteins found in strawberries, birch pollen, and apple indicate that people may develop cross-reactivity to all three species.^[26]

White-fruited strawberry cultivars, lacking Fra a1, may be an option for strawberry allergy sufferers. Since they lack a protein necessary for normal ripening by anthocyanin synthesis of red pigments, the mature berries do not turn red like other cultivars.^[26] They ripen but remain white, pale yellow or "golden", appearing like immature berries; this also has the advantage of making them less attractive to birds. A virtually allergen-free cultivar named 'Sofar' is available.^[27][28]

Strawberries are often grouped according to their flowering habit.^[29][30] Traditionally, this has consisted of a division between "June-bearing" strawberries, which bear their fruit in the early summer and "ever-bearing" strawberries, which often bear several crops of fruit throughout the season.^[30] One plant throughout a season may produce 50 to 60 times or roughly once every three days.^[31]

Strawberries occur in three basic flowering habits: short-day, long-day, and day-neutral. These describe the day-length sensitivity of the plant and the type of photoperiod that induces flower formation. Day-neutral cultivars produce flowers regardless of the photoperiod.^[32]

Strawberry cultivars vary widely in size, color, flavor, shape, degree of fertility, season of ripening, liability to disease and constitution of plant.^[29] On average, a strawberry has about 200 seeds on its external membrane.^[33] Some vary in foliage, while others vary materially in the development of their sexual organs. In most cases, the flowers appear hermaphroditic in structure, but function as either male or female.^[34]

Top Strawberry producers
in 2022
Numbers in million tonnes
1.  China	3.35 (35.01%)
2.  United States	1.26 (13.17%)
3.  Turkey	0.73 (7.63%)
4.  Egypt	0.64 (6.69%)
5.  Mexico	0.57 (5.96%)
6.  Spain	0.33 (3.45%)
World total	9.57
Source: FAOSTAT[35]

In 2022, world production of strawberries was 9.6 million tonnes, led by China with 35% of the total and the United States and Turkey as other significant producers.^[35]

Due to the relatively fragile nature of the strawberry, approximately 35 percent of the $2.2 billion United States crop was spoiled in 2020. An Idaho company announced plans to launch more durable gene-edited strawberries. In the U.S., as of 2021, it cost growers around $35,000 per acre to plant and $35,000 per acre to harvest strawberries.^[36]

For commercial production, plants can be propagated from bare root plants or plugs. One method of cultivation uses annual plasticulture;^[37] another is a perennial system of matted rows or mounds which has been used in cold growing regions for many years.^[38] In some areas, greenhouses are used; in principle they could provide strawberries during the off season for field crops.^[39]

In the plasticulture system, raised beds are covered with plastic to prevent weed growth and erosion. Plants are planted through holes punched in this covering. Irrigation tubing can be run underneath if necessary.^[37][40]

Another method uses a compost sock. Plants grown in compost socks have been shown to produce significantly more flavonoids, anthocyanins, fructose, glucose, sucrose, malic acid, and citric acid than fruit produced in the black plastic mulch or matted row systems.^[41] Similar results in an earlier study conducted by USDA confirms how compost plays a role in the bioactive qualities of two strawberry cultivars.^[42]

Strawberries may be propagated by seed.^[43] Strawberries can be grown indoors in pots.^[44] Strawberries will not grow indoors in winter thoug an experiment using a combination of blue and red LED lamps shows that this could be achieved in principle.^[45] In Florida, winter is the natural growing season and harvesting begins in mid-November.^[31]

• 
  Strawberry field in North Rhine-Westphalia, Germany
• 
  A field using the plasticulture method

Most strawberry plants are now fed with artificial fertilizers, both before and after harvesting, and often before planting in plasticulture.^[46]

To maintain top quality, berries are harvested at least every other day. The berries are picked with the caps still attached and with at least half an inch of stem left. Strawberries need to remain on the plant to fully ripen because they do not continue to ripen after being picked. Rotted and overripe berries are removed to minimize insect and disease problems. The berries do not get washed until just before consumption.^[47]

Soil test information and plant analysis results are used to determine fertility practices. Nitrogen fertilizer is needed at the beginning of every planting year. There are normally adequate levels of phosphorus and potash when fields have been fertilized for top yields. To provide more organic matter, a cover crop of wheat or rye is planted in the winter before planting the strawberries. Strawberries prefer a pH from 5.5 to 6.5, so lime is usually not applied.^[48]

The harvesting and cleaning process has not changed substantially over time. As they are delicate, strawberries are still harvested by hand.^[49] Grading and packing often occurs in the field, rather than in a processing facility.^[49]

Strawberries are popular in home gardens, and numerous cultivars have been selected for consumption and for exhibition purposes.^[50] The following cultivars have gained the Royal Horticultural Society's Award of Garden Merit:

• 'Cambridge Favourite'^[51]
• 'Hapil'^[52]
• 'Honeoye' (/ˈhʌniɔɪ/ HUN-ee-oy)^[53]
• 'Pegasus'^[54]
• 'Rhapsody'^[55]
• 'Symphony'^[56]

In the United States in 2017, the collective commercial production of strawberries, blueberries, raspberries, and blackberries was a $6 billion industry dominated by the California growing and marketing company Driscoll's.^[17] In 2017, strawberries alone were a $3.5 billion market of which 82% was for fresh fruit.^[57]

To increase consumer demand in the 21st century, commercial producers of strawberries cultivated them mainly for favorable aroma characteristics similar to those of wild strawberries,^[18] in addition to having large size, heart-shape, glossy red exterior, and firmness.^[17] Another goal was slow ripening for long shelf-life, enabling ground transportation from farms to stores nationwide for consumption within two weeks of harvest.^[17] In US and Canadian grocery stores, fresh strawberries are typically sold in plastic clamshells, and are among the top fresh produce items in grocery revenues.^[17]

Around 200 species of pests are known to attack strawberries both directly and indirectly.^[58] These pests include slugs, moths, fruit flies, chafers, strawberry root weevils, strawberry thrips, strawberry sap beetles, strawberry crown moth, mites, and aphids.^[58][59] Some are vectors of plant diseases; for instance, the strawberry aphid, Chaetosiphon fragaefolii,^[60] can carry the strawberry mild yellow-edge virus.^[61]

Strawberry plants can fall victim to a number of diseases, especially when subjected to stress.^[62][63] The leaves may be infected by powdery mildew, leaf spot (caused by the fungus Sphaerella fragariae), leaf blight (caused by the fungus Phomopsis obscurans), and by a variety of slime molds.^[62] The crown and roots may fall victim to red stele, verticillium wilt, black root rot, and nematodes.^[62] The fruits are subject to damage from gray mold (Botrytis cinerea), rhizopus rot, and leather rot.^[62]

The NPR1 gene from Arabidopsis thaliana, AtNPR1, confers A. thaliana's broad-spectrum resistance when transexpressed in F. ananassa.^[64] This resistance includes resistance to anthracnose, powdery mildew, and angular leaf spot.^[64]

A 1997 study assessed many wound volatiles and found all effective against gray mold (B. cinerea).^[65] Both Tribute and Chandler were tested and benefited from the treatments, although there are large differences between the substance x variety effects.^[65] Strawberry metabolizes these volatiles, and does so more rapidly than either blackberry or grape.^[65]

The plants can develop disease from temperature extremes during winter.^[62] Watering strawberry roots, and not the leaves, is preferred as moisture on leaves encourages fungal growth.^[66] Strawberries may also often appear conjoined together or deformed due to poor pollination.^[67]

Strawberries were eaten fresh with cream in the time of Thomas Wolsey in the court of King Henry VIII.^[68] Strawberries can be frozen or made into jam or preserves,^[69] as well as dried and used in prepared foods, such as cereal bars.^[70] In the United Kingdom, strawberries and cream is a popular dessert at the Wimbledon tennis tournament.^[68] Desserts using strawberries include pavlova,^[71] fraisier,^[72][73] and strawberry shortcake.^[74]

Polyphenol extracted from strawberries have been used in Kanazawa, Japan, to create melting-resistant popsicles.^[75]

The Roman poet Ovid wrote that in the past Golden Age, people had lived on wild fruits such as mountain strawberries.^[76] Virgil wrote in his Eclogues that "Ye who cull flowers and low-growing strawberries, / Away from here lads; a chill snake lurks in the grass", and his imagery was taken up by medieval and early modern writers, the snake beneath the strawberry standing for dangerous literature, or beautiful but unfaithful women, or eventually any risky pleasure. In this vein, Shakespeare's King Richard III asks for a dish of strawberries while feigning friendship to his enemy; while in Othello, Iago shows Desdemona's handkerchief "spotted with strawberries", implying she has been unfaithful and hinting at Iago's own devious plans.^[76]

The strawberry is found in Italian, Flemish, and German art, and in English miniatures.^[77] In medieval depictions, the strawberry often appears in the Virgin Mary's garden, while in the Madonna of the Strawberries, she is seated on a strawberry bed and garlanded with strawberry leaves.^[76]

In the work of the late medieval painter Hieronymus Bosch, strawberries feature in The Garden of Earthly Delights amongst "frolicking male nudes".^[76] Fray Jose de Siguenza described the painting as embodying the strawberry as a symbol of the ephemerality of earthly joys.^[76] Modern scholars have seen the symbolism entirely differently: Clement Wertheim-Aymes believed it meant the blessed souls' benefit from religion; Pater Gerlach supposed it meant spiritual love; and Laurinda Dixon asserted it was part of an allegory of death and resurrection.^[76] By the late 20th century, the strawberry (and the raspberry) had become "traditional symbols of the mouth and female sexuality".^[78]

• 
  Madonna of the Strawberries, the Upper Rhenish Master, 1420–1430
• 
  Detail of The Garden of Earthly Delights, central panel, man eating a strawberry, Hieronymus Bosch, 1490–1500
• 
  The strawberry girl Ammi Phillips, c. 1830
• 
  Still Life with Strawberry Basket, Severin Roesen, 1860–1871
• 
  Strawberry gatherers, William Gunning King, 1880
• 
  'Strawberry Thief' textile pattern, William Morris, 1883^[79]
• 
  Still Life with Strawberries, Pierre-Auguste Renoir, 1914

• Fragaria × ananassa data from GRIN Taxonomy Database
• Demonstration of strawberry growth lifecycle timelapse on YouTube