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 Plum

General Information

Prunus simonii is a deciduous shrub or a tree with a pyramidal crown; it can grow 5 - 8 metres tall[, ].
The plant is harvested from the wild for local use as a food. It is often cultivated, especially in China, for its edible fruit.

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.

Habitat

Not known in a truly wild situation.

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	6.00 m
Pollinators	Insects
Cultivation Status	Cultivated, Wild

Cultivation Details

Prunus simonii is a fairly cold-hardy plant, tolerating temperatures falling to at least -15°c, but it requires hot summers and distinct changes of season if it is to thrive. In areas with mild winters the plant can be excited into growth too early and is then subject to damage by late frosts[, ].
Thrives in a well-drained moisture-retentive loamy soil, growing well on limestone[, ]. Prefers some lime in the soil but is likely to become chlorotic if too much is present[]. Requires a sunny position[]. Grows well in damp climates but the fruit is then inclined to rot[].
Much cultivated in China for its edible fruit, there are many named cultivars[].
In the USSR this species is of minor horticultural importance as a crop plant. It is suitable for cultivation in the southern regions, particularly in damp areas. One of its shortcomings is the high susceptibility of the fruit to rot[].
In America, it is widely crossed with Prunus salicina to produce valuable commercial varieties. In the USSR, these varieties (Kara and others) endure the climate of Leningrad[].
The hybrid strains are more resistant to rot than Prunus simonii[].
A rather old looking tree at Cambridge Botanical Gardens in England (hardiness zone 7) was only 2.5 metres tall and looking very unhealthy in 1989. It was bearing a few fruits in the September of that year after a very hot summer[]. The tree was not seen in a visit in 1993[].
The plant is widely used in breeding programmes, especially with Prunus salicina, for improved fruiting cultivars[].
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 or cooked. A distinct, unique, slightly tart aroma[]. A fragrant yellow flesh[, ]. Aromatic and very palatable[, ]. The fruit can be very variable in quality, some trees have agreeably flavoured fruits whilst on others the fruit is harsh with an almond-like astringency[, , ]. A very good size, the red, globose fruit is 30 - 60mm in diameter and contains one large seed[, ].

Seed - raw or cooked. Do not eat the seed if it is too bitter - see the notes above on toxicity.

Medicinal

Although no specific mention has been seen for this species, all members of the genus contain amygdalin and prunasin, substances which break down in water to form hydrocyanic acid (cyanide or prussic acid). In small amounts this exceedingly poisonous compound stimulates respiration, improves digestion and gives a sense of well-being[].

Other Uses

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

Seedlings are occasionally used as rootstocks[].

The plant is used in breeding programmes in the USA as a cross-partner for Prunus salicina for developing new plum cultivars[].

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[, ].
Softwood cuttings from strongly growing plants in spring to early summer in a frame[].
Layering in spring.