Prunus Temporal range: | |
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Prunus cerasus (sour cherry) in bloom | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Rosales |
Family: | Rosaceae |
Subfamily: | Amygdaloideae |
Tribe: | Amygdaleae |
Genus: | Prunus L. |
Type species | |
P. domestica | |
Synonyms | |
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Prunus is a genus of trees and shrubs in the flowering plant family Rosaceae that includes plums, cherries, peaches, nectarines, apricots, and almonds. The genus has a cosmopolitan distribution, [3] being native to the North American temperate regions, the neotropics of South America, and temperate and tropical regions of Asia and Africa, [4] There are 340 accepted species. [3] [5] Many members of the genus are widely cultivated for their fruit and for decorative purposes. Prunus fruit are drupes, or stone fruits. The fleshy mesocarp surrounding the endocarp is edible while the endocarp itself forms a hard, inedible shell called the pyrena ("stone" or "pit"). [6] This shell encloses the seed (or "kernel"), which is edible in some species (such as sweet almonds), but poisonous in many others (such as apricots). Besides being eaten off the hand, most Prunus fruit are also commonly used in processing, such as jam production, canning, drying, and the seeds for roasting. [7]
Members of the genus can be deciduous or evergreen. A few species have spiny stems. The leaves are simple, alternate, usually lanceolate, unlobed, and often with nectaries on the leaf stalk along with stipules. The flowers are usually white to pink, sometimes red, with five petals and five sepals. Numerous stamens are present. Flowers are borne singly, or in umbels of two to six or sometimes more on racemes. The fruit is a fleshy drupe (a "prune") with a single relatively large, hard-coated seed (a "stone"). [8]
Within the rose family Rosaceae, it was traditionally placed as a subfamily, the Amygdaloideae (incorrectly "Prunoideae"), but was sometimes placed in its own family, the Prunaceae (or Amygdalaceae). More recently, Prunus is thought to have evolved from within a much larger clade now called subfamily Amygdaloideae (incorrectly "Spiraeoideae"). [2]
The oldest fossils confirmed to belong to Prunus date to the Eocene, and are found across the Northern Hemisphere. Older potential Late Cretaceous records are unconfirmed. [9]
In 1737, Carl Linnaeus used four genera to include the species of modern Prunus—Amygdalus, Cerasus, Prunus, and Padus—but simplified it to Amygdalus and Prunus in 1758. [10] Since then, the various genera of Linnaeus and others have become subgenera and sections, as all the species clearly are more closely related. Liberty Hyde Bailey said: "The numerous forms grade into each other so imperceptibly and inextricably that the genus cannot be readily broken up into species." [11]
Historical treatments break the genus into several different genera, but this segregation is not currently widely recognised other than at the subgeneric rank. The ITIS recognises just the single genus Prunus, with an open list of species, [lower-alpha 1] all of which are given at List of Prunus species. [lower-alpha 2]
One treatment of the subgenera derives from the work of Alfred Rehder in 1940. Rehder hypothesized five subgenera: Amygdalus, Prunus, Cerasus, Padus, and Laurocerasus. [12] To them C. Ingram added Lithocerasus. [13] The six subgenera are described as follows:
An extensive phylogenetic study based on different chloroplast and nuclear sequences divides Prunus into three subgenera: [15]
The lists below are incomplete, but include most of the better-known species.
The genus Prunus includes the almond, the nectarine and peach, several species of apricots, cherries, and plums, all of which have cultivars developed for commercial fruit and nut production. The almond is not a true nut; the edible part is the seed. Other species are occasionally cultivated or used for their seed and fruit.
A number of species, hybrids, and cultivars are grown as ornamental plants, usually for their profusion of flowers, sometimes for ornamental foliage and shape, and occasionally for their bark.
Because of their considerable value as both food and ornamental plants, many Prunus species have been introduced to parts of the world to which they are not native, some becoming naturalised.
The Tree of 40 Fruit has 40 varieties grafted on to one rootstock. [16] [17]
Species such as blackthorn ( Prunus spinosa ), are grown for hedging, game cover, and other utilitarian purposes.
The wood of some species (notably black cherry) is prized as a furniture and cabinetry timber, especially in North America.
Many species produce an aromatic gum from wounds in the trunk; this is sometimes used medicinally. Other minor uses include dye production.
Pygeum, a herbal remedy containing extracts from the bark of Prunus africana , is used as to alleviate some of the discomfort caused by inflammation in patients with benign prostatic hyperplasia.
Prunus species are food plants for the larvae of many Lepidoptera species (butterflies and moths).
Prunus species are included in the Tasmanian Fire Service's list of low flammability plants, indicating that it is suitable for growing within a building protection zone. [18]
Ornamentals include the group that may be collectively called "flowering cherries" (including sakura, the Japanese flowering cherries).
Many species are cyanogenic; that is, they contain compounds called cyanogenic glucosides, notably amygdalin, which, on hydrolysis, yield hydrogen cyanide. [19] Although the fruits of some may be edible by humans and livestock (in addition to the ubiquitous fructivore of birds), seeds, leaves and other parts may be toxic, some highly so. [20] The plants contain no more than trace amounts of hydrogen cyanide, but on decomposition after crushing and exposure to air or on digestion, poisonous amounts may be generated. The trace amounts may give a characteristic taste ("bitter almond") with increasing bitterness in larger quantities, less tolerable to people than to birds, which habitually feed on specific fruits.
People are often encouraged to consume many fruits because they are rich in a variety of nutrients and phytochemicals that are supposedly beneficial to human health. The fruits of Prunus often contain many phytochemicals and antioxidants. [7] [21] [22] These compounds have properties that have been linked to preventing different diseases and disorders. [21] [23] [24] Research suggests that the consumption of these fruits reduces the risk of developing diseases such as cardiovascular diseases, cancer, diabetes, and other age-related declines. [23] [24] Many factors can affect the levels of bioactive compounds in the different fruits of the genus Prunus, including the environment, season, processing methods, orchard operations, and postharvest management. [7]
Cherries contain many different phenolic compounds and anthocyanins, which are indicators of being rich in antioxidants. [25] [23] Recent research has linked the phenolic compounds of the sweet cherry ( Prunus avium ) with antitumor properties. [26]
Reactive oxygen species (ROS) include superoxide radicals, hydrogen peroxide, hydroxyl radicals, and singlet oxygen; they are the byproducts of metabolism. High levels of ROS lead to oxidative stress, which causes damage to lipids, proteins, and nucleic acids. The oxidative damage results in cell death, which ultimately leads to numerous diseases and disorders. Antioxidants act as a defense mechanism against the oxidative stress. [23] [24] They are used to remove the free radicals in a living system that are generated as ROS. [27] [23] Some of those antioxidants include gutathione S-transferase, glutathione peroxidase, superoxide dismutase, and catalase. [27] The antioxidants present in cherry extracts act as inhibitors of the free radicals. [21] However, the DNA and proteins can be damaged when an imbalance occurs in the level of free radicals and the antioxidants. When not enough antioxidants are available to remove the free radicals, many diseases can occur, such as cancers, cardiovascular diseases, Parkinson's disease, etc. [24] Recent studies have shown that using natural antioxidants as a supplement in chemotherapy can decrease the amount of oxidative damage. Some of these natural antioxidants include ascorbic acid, tocopherol, and epigallocatechin gallate; they can be found in certain cherry extracts. [27]
Similar to cherries, strawberries, and raspberries, almonds are also rich in phenolics. Almonds have a high oxygen radical absorbing capacity (ORAC), which is another indicator of being rich in antioxidants. [7] [28] As stated before, high levels of free radicals are harmful, thus having the capacity to absorb those radicals is greatly beneficial. The bioactive compounds, polyphenols and anthocyanins, found in berries and cherries are also present in almonds. [29] [28] Almonds also contain nonflavonoid and flavonoid compounds, which contribute to their antioxidant properties. [7] [30] [28] Flavonoids are a group of structurally related compounds that are arranged in a specific manner and can be found in all vascular plants on land. They also contribute to the antioxidant properties of almonds. [30] Some of the nonflavonoid compounds present are protocatechuic, vanillic, and p-hydroxybenzoic acids. Flavonoid compounds that can be found in the skin of the almond are flavanols, dihydroflavonols, and flavanones. [30] [28]
Of all of the different species of stone fruits, plums are the richest in antioxidants and phenolic compounds. The total antioxidant capacity (TAC) varies within each fruit, but in plums, TAC is much higher in the skin than in the flesh of the fruit. [7] [31] [22]
Apricots are high in carotenoids, which play a key role in light absorption during development. Carotenoids are the pigments that give the pulp and peel of apricots and other Prunus fruits their yellow and orange colors. Moreover, it is an essential precursor for vitamin A, which is especially important for vision and the immune system in humans. [7] [32] Moreover, these fruits are quite rich in phenolic substances, including catechin, epicatechin, p-coumaric acid, caffeic acid, and ferulic acid. [32] [33]
Similar to the plum, peaches and nectarines also have higher TAC in the skin than in the flesh. [7] [31] They also contain moderate levels of carotenoids and ascorbic acid. [34] [31] [22] Peaches and nectarines are orange and yellow in color, which can be attributed to the carotenoids present. [7]
Various Prunus species are winter hosts of the Damson-hop aphid, Phorodon humuli , which is destructive to hops Humulus lupulus just at the time of their maturity, [35] so plum trees should not be grown in the vicinity of hop fields.
Corking is the drying or withering of fruit tissue. [36] In stone fruit, it is often caused by a lack of boron and/or calcium. [37]
Gummosis is a nonspecific condition of stone fruits (peach, nectarine, plum, and cherry) in which gum is exuded and deposited on the bark of trees. Gum is produced in response to any type of wound – insect, mechanical injury, or disease. [38]
Apiosporina morbosa is a major fungal disease in the Northern Americas, with many urban centres running black knot fungus management programs. [39] This disease is best managed by physical removal of knot-bearing branches to prevent spore spread and immediate disposal of infected tissue. [39] Chemical treatment is not largely effective, as trees can easily be re-infected by neighbouring knots.
Laetiporus gilbertsoni (commonly sulfur shelf and chicken of the woods), is a serious cubic brown rot parasite which attacks certain species of decorative red-leaf plum trees in the genus Prunus on the Pacific coast of North America. [40] [41]
This section needs to be updated.(September 2021) |
The earliest known fossil Prunus specimens are wood, drupe, seed, and a leaf from the middle Eocene of the Princeton Chert of British Columbia, Canada. [42] Using the known age as calibration data, a partial phylogeny of some of the Rosaceae from a number of nucleotide sequences was reconstructed. [43] Prunus and its sister clade Maloideae (apple subfamily) has been suggested to have diverged 44.3 million years ago which is within the Lutetian, or older middle Eocene. [lower-alpha 3] Stockey and Wehr report: "The Eocene was a time of rapid evolution and diversification in Angiosperm families such as the Rosaceae ...." [42] The oldest fossil species is Prunus cathybrownae from the Klondike Mountain Formation. [44]
The Princeton finds are among a large number of angiosperm fossils from the Okanagan Highlands dating to the late early and middle Eocene. Crataegus is found at three locations: the McAbee Fossil Beds, British Columbia; the Klondike Mountain Formation around Republic, Washington, and the Allenby Formation around Princeton, British Columbia, while Prunus is found at those locations plus the Coldwater Beds of Quilchena, British Columbia and Chu Chua Formation around Chu Chua, British Columbia. A review of research on the Eocene Okanagan Highlands [45] reported that the Rosaceae were more diverse at higher altitudes. The Okanagan highlands formations date to as early as 52 mya, but the 44.3 mya date[ citation needed ], which is approximate, depending on assumptions, might still apply. The authors state: "... the McAbee flora records a diverse early middle Eocene angiosperm-dominated forest." [45] : 165
The Online Etymology Dictionary presents the customary derivations of plum [46] and prune [47] from Latin prūnum, [48] the plum fruit. The tree is prūnus; [49] and Pliny uses prūnus silvestris to mean the blackthorn. The word is not native Latin, but is a loan from Greek προῦνον (prounon), which is a variant of προῦμνον (proumnon), [50] origin unknown. The tree is προύμνη (proumnē). [51] Most dictionaries follow Hoffman, Etymologisches Wörterbuch des Griechischen, in making some form of the word a loan from a pre-Greek language of Asia Minor, related to Phrygian.
The first use of Prunus as a genus name was by Carl Linnaeus in Hortus Cliffortianus of 1737, [52] which went on to become Species Plantarum . In the latter, Linnaeus attributes the word to "Varr.", who it is assumed must be Marcus Terentius Varro.[ dubious ]
Rosales is an order of flowering plants. It is sister to a clade consisting of Fagales and Cucurbitales. It contains about 7,700 species, distributed into about 260 genera. Rosales comprise nine families, the type family being the rose family, Rosaceae. The largest of these families are Rosaceae (91/4828) and Urticaceae (53/2625). The order Rosales is divided into three clades that have never been assigned a taxonomic rank. The basal clade consists of the family Rosaceae; another clade consists of four families, including Rhamnaceae; and the third clade consists of the four urticalean families.
Rosaceae, the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera.
The peach is a deciduous tree first domesticated and cultivated in Zhejiang province of Eastern China. It bears edible juicy fruits with various characteristics, most called peaches and others, nectarines.
Amygdaloideae is a subfamily within the flowering plant family Rosaceae. It was formerly considered by some authors to be separate from Rosaceae, and the family names Prunaceae and Amygdalaceae have been used. Reanalysis from 2007 has shown that the previous definition of subfamily Spiraeoideae was paraphyletic. To solve this problem, a larger subfamily was defined that includes the former Amygdaloideae, Spiraeoideae, and Maloideae. This subfamily, however, is to be called Amygdaloideae rather than Spiraeoideae under the International Code of Nomenclature for algae, fungi, and plants as updated in 2011.
A cherry is the fruit of many plants of the genus Prunus, and is a fleshy drupe.
An apricot is a fruit, or the tree that bears the fruit, of several species in the genus Prunus.
A plum is a fruit of some species in Prunus subg. Prunus. Dried plums are most often called prunes, though in the United States they may be just labeled as 'dried plums', especially during the 21st century.
In botany, a drupe is an indehiscent type of fruit in which an outer fleshy part surrounds a single shell of hardened endocarp with a seed (kernel) inside. These fruits usually develop from a single carpel, and mostly from flowers with superior ovaries.
Prunus subg. Padus is a subgenus of Prunus, characterised by having racemose inflorescences. Padus was originally a distinct genus, but genetic and morphological studies have shown that Padus is polyphyletic. It has been proposed that all the racemose taxa within Prunus are incorporated into a broad-sense Prunus subg. Padus.
Prunus serotina Ehrh., commonly called black cherry, wild black cherry, rum cherry, or mountain black cherry, is a deciduous tree or shrub in the rose family Rosaceae. Despite being called black cherry, it is not very closely related to the commonly cultivated cherries such as sweet cherry, sour cherry and Japanese flowering cherries which belong to Prunus subg. Cerasus. Instead, P. serotina belongs to Prunus subg. Padus, a subgenus also including Eurasian bird cherry and chokecherry. The species is widespread and common in North America and South America.
Prunus salicina, commonly called the Japanese plum or Chinese plum, is a small deciduous tree native to China. It is now also grown in fruit orchards in Vietnam, Korea, Japan, Israel, the United States, and Australia.
Plum pox, also known as sharka, is the most devastating viral disease of stone fruit from the genus Prunus. The disease is caused by the plum pox virus (PPV), and the different strains may infect a variety of stone fruit species including peaches, apricots, plums, nectarine, almonds, and sweet and tart cherries. Wild and ornamental species of Prunus may also become infected by some strains of the virus.
Prune dwarf virus (PDV) is an economically important plant pathogenic virus affecting Prunus species globally. PDV is found worldwide due to easy transmission through seed, pollen, and vegetative propagation. The virus is in the family Bromoviridae an important family of plant RNA viruses containing six genera, including Alfamovirus, Ilarvirus, Bromovirus, Amularvirus, Oleavirus, and Cucumovirus. PDV belongs to the genera Ilarvirus. It can cause dwarfism of leaves on certain prune and plum plants. It will also cause yellows in sour cherry, especially when present with Prunus necrotic ringspot virus. There are no known transmission vectors, though the pollen of infected cherry trees has been found to infect other cherry trees a small percent of the time.
Prunus tenella, the dwarf Russian almond, is a species of deciduous shrub in the genus Prunus, native to steppes of Eastern Europe and Western Siberia, as well as dry open sites of Caucasus, Western and Central Asia.
Taphrina pruni is a fungal plant pathogen of blackthorn that causes the pocket or bladder plum gall, a chemically induced distortion of the fruit (sloes), producing swollen on one side, otherwise deformed and flattened fruit gall without a stone. The twigs on infected plants may also be deformed with small strap-shaped leaves.
Prunus subg. Prunus is a subgenus of Prunus. This subgenus includes plums, apricots and bush cherries. Some species conventionally included in Prunus subg. Amygdalus are clustered with plum/apricot species according to molecular phylogenetic studies. Shi et al. (2013) has incorporated subg. Amygdalus into subg. Prunus, thereby including almonds and peaches in this subgenus. The species in this subgenus have solitary flowers or 2–3 in a fascicle.
Prunus tianshanica, the Tianshan cherry, is a species of cherry native to the Tianshan Mountains of Central Asia, preferring to grow at 800-1000 m.
Prunus subg. Cerasus is a subgenus of Prunus. Species of the subgenus have a single winter bud per axil. The flowers are usually in small corymbs or umbels of several together, but some species have short racemes. The fruit is a drupe and has no obvious groove along the side. The subgenus is native to the temperate regions of the Northern Hemisphere, with two species in North America, four in Europe, two in North Africa, and the remainder in Asia.
Prunus sect. Microcerasus is a section of Prunus. It used to be included in Prunus subg. Cerasus, but phylogenetic research indicates it belongs to Prunus subg. Prunus. It differs from Prunus subg. Cerasus by having three winter buds per axil.
Candidatus Phytoplasma pruni is a species of phytoplasma in the class Mollicutes, a class of bacteria distinguished by the absence of a cell wall. The specific epithet pruni means "living on Prunus", emphasizing the fact that the phytoplasma is a parasite of various Prunus species, otherwise known as stone fruits. The phytoplasma is commonly called the X-disease phytoplasma.