In spite of their wide geographic distribution, the various species in the genus Pyrus are intercrossable without major incompatibility barriers. Also, the high morphological diversity and the lack of distinguishing characters among the species have been reported. Therefore, the classification of species in this genus is problematic and often confusing, giving different populations designated as different species by some authors. It is likely that, when the genus is reviewed, there will be several changes to the nomenclature[].

Common Name: Asian Pear

General Information

Pyrus pyrifolia culta is a deciduous tree that can grow from 7 - 15 metres tall[].
The Asian Pear is much appreciated for its crisp, juicy fruits and has a history of cultivation dating back at least 2,000 years. It is widely cultivated for its edible fruit, especially in China and Japan, but increasingly in other regions of the temperate and subtropical zones[, ]. The plant also has a range of medicinal uses and a useful wood.

Known Hazards

Although no specific information has been seen for this plant, the seed of many species in the family Rosaceae are likely to contain cyanogenic glycosides. 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 levels of toxin can be detected by the level of bitterness:- sweet almonds, for example, contain only very low levels of it and are safe to eat in quantity, whilst bitter almonds (which are used as a flavouring in foods such as marzipan) contain much higher levels and should only be eaten in very small quantities. Great caution should be employed if the taste is moderately to very bitter[].

Botanical References

,

Range

A cultivated form of Pyrus pyrifolia.

Habitat

Not known in the wild.

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	10.00 m
Pollinators	Bees, Insects
Cultivation Status	Cultivated

Cultivation Details

Pyrus pyrifolia culta is very cold-hardy, tolerating temperatures down to at least -15°c when dormant[]. It also has lower chilling requirements than most other Pyrus species and has been cultivated successfully in highland regions of the tropics, especially in Thailand, Indonesia and the Philippines[].
Prefers a good well-drained loam in full sun[]. Grows well in heavy clay soils. Tolerates light shade but does not fruit so well in such a position. Tolerates atmospheric pollution, excessive moisture and a range of soil types if they are moderately fertile[]. Established plants are drought tolerant[].
Cultivated for its edible fruit in China and Japan, there are more than 1,000 named varieties[, ].
Under the very intensive management system in Japan, yields of 45 tonnes per hectare per year of excellent quality fruits can be obtained[]. Average commercial production is usually 25 - 40 tonnes[].
Self-incompatibility is common, but parthenocarpic fruit set occurs[].
A hybrid between this plant and Pyrus communis culta is more suitable for warmer climates[].

Edible Uses

Fruit - raw or cooked[, ]. Crisp, juicy with a fine flavour[]. The best cultivars produce fruit of supreme quality[]. Fruit of indifferent cultivars is sometimes dried or candied[]. The ideal oriental pear has firm, crisp, juicy flesh, without stone cells. The taste should be very sweet with a delicate flavour reminiscent of cucumber and rosewater, the skin golden yellow or silvery green and with no russeting or blemishes[]. Generally, the fruits are eaten shortly after harvest, though some forms can store for up to 6 weeks[]. The fruit contains about 6 - 9.5% sugar and up to 0.56% fruit acids[].

Medicinal

The fruit is considered to be febrifuge, nervine, pectoral[].

The leaves are astringent[].

The bark is antiseptic[].

Other Uses

The flowers are used in cosmetic preparations[].

The wood is of good quality. It is used for making furniture[].

Propagation

Seed - best sown in a cold frame as soon as it is ripe in the autumn, it will then usually germinate in mid to late winter. Stored seed requires 8 - 10 weeks cold stratification at 1°c and should be sown as early in the year as possible[]. Temperatures over 15 - 20°c induce a secondary dormancy in the seed[]. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in light shade in a cold frame or greenhouse for their first year. Plant them out in late spring or early summer of the following year. The seed of pear cultivars will not usually breed true to type.