Morus (plant)

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Mulberry
Morus alba FrJPG.jpg
Morus nigra
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Rosales
Family: Moraceae
Tribe: Moreae
Genus: Morus
L.
Species

See text.

Morus, a genus of flowering plants in the family Moraceae, consists of diverse species of deciduous trees commonly known as mulberries, growing wild and under cultivation in many temperate world regions. [1] [2] [3] Generally, the genus has 64 subordinate taxa, [4] three of which are well-known and are ostensibly named for the fruit color of the best-known cultivar: white, red, and black mulberry ( Morus alba , M. rubra , and M. nigra , respectively), with numerous cultivars and some taxa currently unchecked and awaiting taxonomic scrutiny. [5] [4] M. alba is native to South Asia, but is widely distributed across Europe, Southern Africa, South America, and North America. [2] M. alba is also the species most preferred by the silkworm, and is regarded as an invasive species in Brazil and the United States. [2]

Contents

The closely related genus Broussonetia is also commonly known as mulberry, notably the paper mulberry (Broussonetia papyrifera). [6]

Despite their similar appearance, mulberries are not closely related to raspberries or blackberries. All three species belong to the Rosales order. But while the mulberry is a tree belonging to the Moraceae family (also including the fig, jackfruit, and other fruits), raspberries and blackberries are brambles and belong to the Rosaceae family (also including the apple, peach, and other fruits).

Description

Mulberries are fast-growing when young, and can grow to 24 metres (79 feet) tall. [2] [5] The leaves are alternately arranged, simple, and often lobed and serrated on the margin. Lobes are more common on juvenile shoots than on mature trees. [2] [5] The trees can be monoecious or dioecious. [5]

The mulberry fruit is a multiple, about 2–3 centimetres (341+14 inches) long. [2] [5] Immature fruits are white, green, or pale yellow. [5] The fruit turns from pink to red while ripening, then dark purple or black, and has a sweet flavor when fully ripe. [2] [5]

Taxonomy

The taxonomy of Morus is complex and disputed. Fossils of Morus appear in the Pliocene record of the Netherlands. [7] Over 150 species names have been published, and although differing sources may cite different selections of accepted names, less than 20 are accepted by the vast majority of botanical authorities. Morus classification is even further complicated by widespread hybridisation, wherein the hybrids are fertile.[ citation needed ]

The following species are accepted: [8]

In southern Brazil, the mulberry is known as amorinha. [9]

Distribution

Mulberry fruit in Libya Mulberry in Libya.jpg
Mulberry fruit in Libya

Black, red, and white mulberries are widespread in Southern Europe, the Middle East, Northern Africa, and the Indian subcontinent, where the tree and the fruit have names under regional dialects. Black mulberry was imported to Britain in the 17th century in the hope that it would be useful in the cultivation of silkworms. It was much used in folk medicine, especially in the treatment of ringworm. Mulberries are also widespread in Greece, particularly in the Peloponnese, which in the Middle Ages was known as Morea, deriving from the Greek word for the tree ( μουριά , mouria).

Cultivation

A mulberry tree in England Canons Ashby House and Mulberry Tree - geograph.org.uk - 22987.jpg
A mulberry tree in England

Mulberries can be grown from seed, and this is often advised, as seedling-grown trees are generally of better shape and health. Mulberry trees grown from seed can take up to ten years to bear fruit. Mulberries are most often planted from large cuttings, which root readily. The mulberry plants allowed to grow tall have a crown height of 1.5 to 1.8 m (5 to 6 ft) from ground level and a stem girth of 10–13 cm (4–5 in). They are specially raised with the help of well-grown saplings 8–10 months old of any of the varieties recommended for rainfed areas like S-13 (for red loamy soil) or S-34 (black cotton soil), which are tolerant to drought or soil-moisture stress conditions. Usually, the plantation is raised and in block formation with a spacing of 1.8 by 1.8 m (6 by 6 ft), or 2.4 by 2.4 m (8 by 8 ft), as plant-to-plant and row-to-row distances. The plants are usually pruned once a year during the monsoon season to a height of 1.5–1.8 m (5–6 ft) and allowed to grow with a maximum of 8–10 shoots at the crown. The leaves are harvested three or four times a year by a leaf-picking method under rain-fed or semiarid conditions, depending on the monsoon. The tree branches pruned during the fall season (after the leaves have fallen) are cut and used to make durable baskets supporting agriculture and animal husbandry.

Some North American cities have banned the planting of mulberries because of the large amounts of pollen they produce, posing a potential health hazard for some pollen allergy sufferers. [10] Actually, only the male mulberry trees produce pollen; this lightweight pollen can be inhaled deeply into the lungs, sometimes triggering asthma. [11] [12] Conversely, female mulberry trees produce all-female flowers, which draw pollen and dust from the air. Because of this pollen-absorbing feature, all-female mulberry trees have an OPALS allergy scale rating of just 1 (lowest level of allergy potential), and some consider it "allergy-free". [11]

Mulberry tree scion wood can easily be grafted onto other mulberry trees during the winter, when the tree is dormant. One common scenario is converting a problematic male mulberry tree to an allergy-free female tree, by grafting all-female mulberry tree scions to a male mulberry that has been pruned back to the trunk. [13] However, any new growth from below the graft(s) must be removed, as they would be from the original male mulberry tree. [14]

Toxicity

All parts of the plant besides the ripe fruit contain a toxic milky sap. [15] Eating too many berries may have a laxative effect. Additionally, unripe green fruit may cause nausea, cramps, and a hallucinogenic effect. [16]

Uses

Nutrition

Raw mulberries
Nutritional value per 100 g (3.5 oz)
Energy 180 kJ (43 kcal)
9.8
Sugars 8.1
Dietary fiber 1.7
Fat
0.39
1.44
Vitamins Quantity
%DV
Vitamin A equiv.
0%
1 μg
Thiamine (B1)
2%
0.029 mg
Riboflavin (B2)
8%
0.101 mg
Niacin (B3)
4%
0.62 mg
Vitamin B6
3%
0.05 mg
Folate (B9)
2%
6 μg
Vitamin C
40%
36.4 mg
Vitamin E
6%
0.87 mg
Vitamin K
7%
7.8 μg
Minerals Quantity
%DV
Calcium
3%
39 mg
Iron
10%
1.85 mg
Magnesium
4%
18 mg
Phosphorus
3%
38 mg
Potassium
6%
194 mg
Sodium
0%
10 mg
Zinc
1%
0.12 mg
Other constituentsQuantity
Water87.68 g

Percentages estimated using US recommendations for adults, [17] except for potassium, which is estimated based on expert recommendation from the National Academies. [18]

Raw mulberries are 88% water, 10% carbohydrates, 1% protein, and less than 1% fat. In a 100-gram (3.5-ounce) reference amount, raw mulberries provide 43 calories, 44% of the Daily Value (DV) for vitamin C, and 14% of the DV for iron; other micronutrients are insignificant in quantity.

Culinary

As the fruit matures, mulberries change in texture and color, becoming succulent, plump, and juicy, resembling a blackberry. [5] The color of the fruit does not distinguish the mulberry species, as mulberries may be white, lavender or black in color. White mulberry fruits are typically sweet, but not tart, while red mulberries are usually deep red, sweet, and juicy. Black mulberries are large and juicy, with balanced sweetness and tartness. [5]

The fruit of the East Asian white mulberry – a species extensively naturalized in urban regions of eastern North America – has a different flavor, sometimes characterized as refreshing and a little tart, with a bit of gumminess to it and a hint of vanilla. [19] In North America, the white mulberry is considered an invasive exotic and has taken over extensive tracts from native plant species, including the red mulberry. [2] [20]

Mulberries are used in pies, tarts, wines, cordials, and herbal teas. [2] [5] The fruit of the black mulberry (native to southwest Asia) and the red mulberry (native to eastern North America) have distinct flavors likened to 'fireworks in the mouth'. [19] Jams and sherbets are often made from the fruit in the Old World.

The tender twigs are semisweet and can be eaten raw or cooked. [21]

Supplement

The fruit and leaves are sold in various forms as dietary supplements.[ citation needed ]

Silk industry

A silkworm, Bombyx mori, feeding on a mulberry tree Silkworm mulberry tree zetarra marugatze arbolean3.JPG
A silkworm, Bombyx mori , feeding on a mulberry tree

Mulberry leaves, particularly those of the white mulberry, are ecologically important as the sole food source of the silkworm (Bombyx mori, named after the mulberry genus Morus), the cocoon of which is used to make silk. [22] [23] The wild silk moth also eats mulberry. [24] [25] Other Lepidoptera larvae which include the common emerald, lime hawk-moth, sycamore moth, and fall webworm also eat the plant. [26]

The Ancient Greeks and Romans cultivated the mulberry for silkworms; at least as early as 220 AD, Emperor Elagabalus wore a silk robe. [27] English clergy wore silk vestments from about 1500 onwards. [27] Mulberry and the silk industry played a role in colonial Virginia. [27]

Pigment

Mulberry fruit color derives from anthocyanins, [3] which have unknown effects in humans. [28] Anthocyanins are responsible for the attractive colors of fresh plant foods, including orange, red, purple, black, and blue. [28] These colors are water-soluble and easily extractable, yielding natural food colorants. [2] Due to a growing demand for natural food colorants, they have numerous applications in the food industry. [3] [28]

A cheap and industrially feasible method has been developed to extract anthocyanins from mulberry fruit that could be used as a fabric dye or food colorant of high color value (above 100). [2] Scientists found that, of 31 Chinese mulberry cultivars tested, the total anthocyanin yield varied from 148 to 2725 mg/L of fruit juice. [29] Sugars, acids, and vitamins of the fruit remained intact in the residual juice after removal of the anthocyanins, indicating that the juice may be used for other food products. [29] [2]

Mulberry germplasm resources may be used for: [3] [2] [30]

Paper

During the Angkorian age of the Khmer Empire of Southeast Asia, monks at Buddhist temples made paper from the bark of mulberry trees. The paper was used to make books, known as kraing . [31]

Tengujo is the thinnest paper in the world. It is produced in Japan and made with kozo (stems of mulberry trees). [32]

Wood

The wood of mulberry trees is used for barrel aging of Țuică, a traditional Romanian plum brandy.

Culture

Mulberry Tree by Vincent van Gogh The Mulberry Tree by Vincent van Gogh.jpg
Mulberry Tree by Vincent van Gogh

A Babylonian etiological myth, which Ovid incorporated in his Metamorphoses , attributes the reddish-purple color of the mulberry fruits to the tragic deaths of the lovers Pyramus and Thisbe. Meeting under a mulberry tree (probably the native Morus nigra ), [33] Thisbe commits suicide by sword after Pyramus does the same, he having believed, on finding her bloodstained cloak, that she was killed by a lion. Their splashed blood stained the previously white fruit, and the gods forever changed the mulberry's colour to honour their forbidden love. [33]

The nursery rhyme "Here We Go Round the Mulberry Bush" uses the tree in the refrain, as do some contemporary American versions of the nursery rhyme "Pop Goes the Weasel".[ citation needed ]

Vincent van Gogh featured the mulberry tree in some of his paintings, notably Mulberry Tree (Mûrier, 1889, now in Pasadena's Norton Simon Museum). He painted it after a stay at an asylum, and he considered it a technical success. [34]

Related Research Articles

<span class="mw-page-title-main">Moraceae</span> Family of flowering plants

The Moraceae—often called the mulberry family or fig family—are a family of flowering plants comprising about 38 genera and over 1100 species. Most are widespread in tropical and subtropical regions, less so in temperate climates; however, their distribution is cosmopolitan overall. The only synapomorphy within the Moraceae is presence of laticifers and milky sap in all parenchymatous tissues, but generally useful field characters include two carpels sometimes with one reduced, compound inconspicuous flowers, and compound fruits. The family includes well-known plants such as the fig, banyan, breadfruit, jackfruit, mulberry, and Osage orange. The 'flowers' of Moraceae are often pseudanthia.

<span class="mw-page-title-main">Sycamine</span> Tree mentioned in ancient literature

The sycamine tree is a tree mentioned in both classical Hebrew literature and in Greek literature. The tree is also known by the names sycamore fig tree, and fig-mulberry. It appears also in Luke 17:6 and 19:4 of the Bible. The Hebrew word for the tree is shiḳmah (sing.), shiḳmīn (pl.), having nearly the same phonemes in Greek Others, however, identify the tree as mulberry tree, found in two species, the Black Mulberry and the White Mulberry, which are common in Palestine. It is in the same family as the fig-tree.

The bricks are fallen, but we will build with hewn stones; the sycamores are cut down, but cedars will we put in their place.

<i>Morus alba</i> Species of plant

Morus alba, known as white mulberry, common mulberry and silkworm mulberry, is a fast-growing, small to medium-sized mulberry tree which grows to 10–20 m (33–66 ft) tall. It is generally a short-lived tree with a lifespan comparable to that of humans, although there are some specimens known to be more than 250 years old. The species is native to China and India and is widely cultivated and naturalized elsewhere.

<i>Maclura tricuspidata</i> Species of tree

Maclura tricuspidata is a tree native to East Asia, occasionally grown for its fruit, somewhat similar to that of the related mulberry. It is also known by common names including cudrang, kujibbong, storehousebush, mandarin melon berry, silkworm thorn, zhe or che, and Chinese mulberry. It grows up to 6 m high.

Chinese mulberry is a common name for several trees and may refer to:

<span class="mw-page-title-main">Paper mulberry</span> Species of plant

The paper mulberry is a species of flowering plant in the family Moraceae. It is native to Asia, where its range includes mainland China, Taiwan, Japan, Korea, Southeast Asia, Myanmar, and India. It is widely cultivated elsewhere and it grows as an introduced species in New Zealand, parts of Europe, the United States, and Africa. Other common names include tapa cloth tree.

<i>Morus rubra</i> Species of tree

Morus rubra, commonly known as the red mulberry, is a species of mulberry native to eastern and central North America. It is found from Ontario, Minnesota, and Vermont south to southern Florida, and west as far as southeastern South Dakota, Nebraska, Kansas, and central Texas. There have been reports of isolated populations in New Mexico, Idaho, and British Columbia.

<i>Broussonetia</i> Species of plant

Broussonetia is a genus of four species of trees in the family Moraceae, native to eastern Asia. These four species have high-quality fiber which consist of more than 90% of cellulose. They are traditionally applied for various daily necessities in South Eastern Asia and papermaking in East Asia.

<i>Sambucus nigra</i> Species of flowering plant in the moschatel family Adoxaceae

Sambucus nigra is a species complex of flowering plants in the family Adoxaceae native to most of Europe. Common names include elder, elderberry, black elder, European elder, European elderberry, and European black elderberry. It grows in a variety of conditions including both wet and dry fertile soils, primarily in sunny locations. The plant is widely grown as an ornamental shrub or small tree. Both the flowers and the berries have a long tradition of culinary use, primarily for cordial and wine.

Morus serrata, known as Himalayan mulberry, is a species of mulberry native to the Himalaya and the mountains of southwestern China, at altitudes of up to 2,300 metres.

<i>Morus nigra</i> Species of tree

Morus nigra, called black mulberry, is a species of flowering plant in the family Moraceae that is native to southwestern Asia, where it has been cultivated for so long that its precise natural range is unknown. The black mulberry is known for its large number of chromosomes.

<span class="mw-page-title-main">Moreae</span> Tribe of flowering plants

Moreae is a tribe within the plant family Moraceae. It includes 6–10 genera and 70–80 species, including Morus, the genus that includes the mulberries, and Maclura, the genus that includes the Osage orange.

<i>Morus australis</i> Species of tree

Morus australis, also called Korean mulberry and Chinese mulberry, is a flowering plant species found in East and Southeast Asia.

<i>Morus celtidifolia</i> Species of flowering plant

Morus celtidifolia, the Texas mulberry, is a plant species native to South America, Central America, Mexico, and the southwestern United States, ranging from Argentina north as far as Arizona and Oklahoma. In the US, it grows in canyons and on slopes, usually near streams, from 200–2,200 metres in elevation. It is very often referred to as "Morus microphylla," including in Flora of North America, but recent studies suggest that these names are synonymous with M. celtidifolia holding priority.

<span class="mw-page-title-main">Mulberry Garden (Režný Újezd)</span>

The Mulberry garden, originally Morušová zahrada in Czech, is a cottage garden in the Czech Republic, situated in the Czech Central Uplands in the village Režný Újezd, 7 kilometres (4.3 mi) northwest of the town Lovosice. The garden was established in 2014 by local gardeners admiring the English cottage garden style. Apart from different kinds of plants such as perennial plants, English historical roses, Czech roses, annual plants, and bulbs, several uncommon fruit trees are grown, especially various mulberry varieties. Mulberry garden is located along the green tourist track to Boreč hill in the grounds of former Gentlemen's farm, house no. 2.

<i>Morus indica</i> Berry and plant

Morus indica is a member of the genus Morus, of the family of flowering plants Moraceae, commonly known as the mulberry family. As with other mulberries, Morus indica is a deciduous tree. Morus indica is native to the temperate and sub-tropical Himalayan region. It is currently cultivated in India, China, Japan, and East Africa.

<i>Morus mongolica</i> Species of fruit and plant

Morus mongolica, also described as Morus alba var. mongolica, is a woody plant native to mountain forests in Mongolia, China, Korea, and Japan. Common names include Mongolian mulberry, meng sang (China), and ilama by native people in the namesake region of Mongolia. Similar to M. notabilis, M. mongolica is an uncultivated mulberry.

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