The taxonomic history of Prunus is long and complicated, in part due to the economic value of its fruit crops and also the ease with which some species hybridize. Here, Prunus is circumscribed in its broad sense based on the argument that when viewed on a worldwide scale, the morphologic discontinuities among the segregate genera diminish and they overlap with one another. Included here are species that have at times been placed in the genera Amygdalus, Armeniaca, Cerasus, Laurocerasus, Padus, and Persica.
At the species level, Prunus has been the object of the usual combining and splitting common among taxonomists with different philosophies and opinions. In particular, over-reliance on the indument of various vegetative and floral parts has led to the naming of numerous species and infraspecific taxa. Similarly, too much has been made of fruit colour and palatability in naming taxa of Prunus. It is very likely that, as molecular and genetic data are analyzed and, more importantly, correlated with morphological data, circumscriptions will be redrawn and the number of Prunus species will be reduced[].

Common Name: Apricot

General Information

Prunus armeniaca is a deciduous tree with sturdy, tortuous branches forming a rounded canopy; it can grow 5 - 10 metres tall[, ].
The apricot has a long history of cultivation, dating back in China to around 2,000 BCE. It is often cultivated as a fruit crop in many areas of the temperate and subtropical zones - the fruits mainly being dried or processed due to the difficulty of bringing them fresh to the market in good condition. The tree also produces edible seeds and oil, has a range of medicinal applications and yields a good quality wood.

Known Hazards

The plant (especially the seed and young shoots) contains cyanogenic glycosides, especially amygdalin and prunasin. When injested, these compounds break down in the digestive tract to release cyanide. Used in small quantities in both traditional and conventional medicine, this exceedingly poisonous compound has been shown to stimulate respiration, improve digestion, and promote a sense of well-being[]. It is also claimed by some to be of benefit in the treatment of cancer - though this claim has been largely refuted.
In larger concentrations, however, cyanide can cause gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma and respiratory failure leading to death[].
The fruits and flowers of most members of this genus generally have low or very low concentrations of this toxin, though the seeds and young shoots can contain much higher levels.
The levels of toxin can be detected by the level of bitterness:- for example sweet tasting almond seeds are a major food crop and are often eaten in quantity, whilst bitter tasting almond seeds are used as a flavouring (in marzipan for example) but are not usually eaten on their own.
In general, it can be considered safe to eat any fruit or seed from species in this genus that either have a sweet flavour or are slightly bitter. Great caution should be taken, however, if the flavour is moderately to very bitter[].

Botanical References

, ,

Range

E. Asia - N. China, Mongolia.

Habitat

Most trees growing apparently wild have escaped from cultivation but there are pure stands of the trees in western China, growing on mountain slopes in sparse forests at elevations from 700 - 3,000 metres[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	9.00 m
Growth Rate	Medium
Pollinators	Insects
Self-fertile	Yes
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

The apricot grows best in warm temperate and subtropical zones. It prefers a more continental climate, with its clearly defined seasons, and can be very disappointing in more maritime areas with mild winters that can excite it into growth only for the flowers and young leaves to be damaged by late frosts. In such areas, growing the plant against a sunny wall (preferably facing the afternoon sun since this will give extra frost protection) can produce good crops of fruit[, ].
Requires a well-drained moisture retentive fertile soil in a warm sunny position[, ]. Succeeds in light shade but fruits better in a sunny position[]. Thrives in a loamy soil, doing well on limestone[]. Prefers some chalk in the soil but is apt to become chlorotic if too much is present[]. Prefers a pH in the range 6.5 to 7.5[]. Dislikes clay soils[, ]. Intolerant of saline soils[]. Trees drop their fruit buds if there is a summer drought[].
The apricot is widely cultivated for its edible fruit in temperate areas that have long hot summers and also in the subtropics[]. There are many named varieties[, ]. The fruit is often grown on a garden scale, when it is usually eaten fresh, there is little market for commercially grown fresh apricots, however, because of their extremely short shelf life - most of these fruits are preserved by drying or made into preserves etc[].
The plants are self-fertile[], but hand pollination would be advisable since they are normally flowering before many pollinating insects are active.
In Britain apricots are usually grown on plum rootstocks, 'St. Julien A' is the most widely used[]. The dwarfing rootstock 'Pixie' is also a possibility, but this must be double worked with 'St. Julien A' because it is incompatible with apricots[].
Any pruning should be carried out in the summer to allow rapid healing and therefore less risk of infection[].
Most members of this genus are shallow-rooted and will produce suckers if the roots are damaged[].
Plants in this genus are notably susceptible to honey fungus[].

Edible Uses

Fruit - raw, cooked or dried for later use[, , , ]. The best forms are soft and juicy with a delicious rich flavour[]. Mainly grown on a garden scale for eating fresh because of the difficulty of getting ripe fruit to market in good condition, commercially cultivaed fruits are mainly processed to preserves, jams, marmalades and pure and mixed juices[]. Wild trees in the Himalayas yield about 47.5kg of fruit per year[].The fruit of the wild form contains about 6.3% sugars, 0.7% protein, 2.5% ash, 2.5% pectin. There is about 10mg vitamin C per 100g of pulp[]. The globose fruit is yellow, tinged with red. Around 30mm in diameter in wild forms, the fruit of cultivated plants can be 50mm or more in diameter and contain one large seed[, ].

Seed - raw or cooked[]. Rich in oils and protein[]. Bitter seeds should be eaten in strict moderation, but sweet ones can be eaten freely[]. The bitter seeds can be used as a substitute for bitter almonds in making marzipan etc[].

An edible gum is obtained from the trunk[].

The seed contains up to 50% of an edible semi-drying oil[, , , ]. It is used in cooking[].

Medicinal

Apricot fruits contain citric and tartaric acid, carotenoids and flavonoids[]. They are nutritious, cleansing and mildly laxative[254. They are a valuable addition to the diet working gently to improve overall health. The salted fruit is antiinflammatory and antiseptic[]. It is used medicinally in Vietnam in the treatment of respiratory and digestive diseases[].
Antipyretic, antiseptic, emetic, ophthalmic[].

The flowers are tonic, promoting fecundity in women[].

The bark is astringent[]. The inner bark and/or the root are used for treating poisoning caused by eating bitter almond and apricot seeds (which contain hydrogen cyanide)[]. Another report says that a decoction of the outer bark is used to neutralize the effects of hydrogen cyanide[]. The decoction is also used to soothe inflamed and irritated skin conditions[].

The seed is analgesic, anthelmintic, antiasthmatic, antispasmodic, antitussive, demulcent, emollient, expectorant, pectoral, sedative and vulnerary[, ]. It is used in the treatment of asthma, coughs, acute or chronic bronchitis and constipation[, ].
The seed contains 'laetrile', a substance that has also been called vitamin B17[]. This has been claimed to have a positive effect in the treatment of cancer, but there does not at present seem to be much evidence to support this[]. The pure substance is almost harmless, but on hydrolysis it yields hydrocyanic acid, a very rapidly acting poison - it should thus be treated with caution[]. In small amounts this exceedingly poisonous compound stimulates respiration, improves digestion and gives a sense of well-being[].

Agroforestry Uses:

The plant is traditionally grown in living fences in the northwestern Himalayas, where it helps to exclude livestock and other animals; mark out land boundaries; whilst also providing a range of medicinal and other uses[].
Oats should not be grown near apricots because their roots have an antagonistic effect on the roots of the apricot[]. Tomatoes and potatoes are also bad companions for apricots[]. If nasturtiums (Tropaeoleum spp) are grown under apricots they will make the fruit less palatable to insects, though this is not detectable by the human palate[].

Other Uses

An edible semi-drying oil is obtained from the seed[]. It can be used in light industry and is also used for lighting[, , ]. The oil has a softening effect on the skin and so it is used in perfumery, cosmetics and as a hair oil. It is also used in pharmaceuticals[, , ].

A green dye can be obtained from the leaves[].
A dark grey to green dye can be obtained from the fruit[].

The heartwood is greyish-brown, mottled with dark brown streaks; the sapwood is white. The grain is close and even, the wood is moderately hard, durable. A handsome wood of high quality, it can be used for a wide range of items including agricultural implements etc[, , ].

Propagation

Seed - requires 2 - 3 months cold stratification and is best sown in a cold frame as soon as it is ripe[]. Sow stored seed in a cold frame as early in the year as possible[]. Protect the seed from mice etc. The seed can be rather slow, sometimes taking 18 months to germinate[]. Prick out the seedlings into individual pots when they are large enough to handle. Grow them on in a greenhouse or cold frame for their first winter and plant them out in late spring or early summer of the following year.
Cuttings of half-ripe wood with a heel, mid summer in a frame[, ]. Difficult[].
Softwood cuttings from strongly growing plants in spring to early summer in a frame[]. Difficult.
Layering in spring.