苹果：
The apple is a tree and its pomaceous fruit, of the species Malus domestica in the rose family Rosaceae. It is one of the most widely cultivated tree fruits. It is a small deciduous tree reaching 5-12 m tall, with a broad, often densely twiggy crown. The leaves are alternately arranged, simple oval with an acute tip and serrated margin, slightly downy below, 5-12 cm long and 3-6 cm broad on a 2-5 cm petiole. The flowers are produced in spring with the leaves, white, usually tinged pink at first, 2.5-3.5 cm diameter, with five petals. The fruit matures in Autumn, and is typically 5-8 cm diameter (rarely up to 15 cm).
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Apple tree in flower
Botanical origins
Wild Malus sieversii apple in KazakhstanThe wild ancestor of Malus domestica is Malus sie
versii. It has no common name in English, but is known where it is native as "alma"; in fact, one major city in the region where it is thought to originate is called Alma-Ata, or "father of the apples". This tree is still found wild in the mountains of Central Asia in southern Kazakhstan, Kyrgyzstan, Tajikistan, and Xinjiang, China.
For many years, there was a debate about whether M. domestica evolved from chance hybridization among various wild species. Recent DNA analysis by Barrie Juniper, Emeritus Fellow in the Department of Plant Sciences at Oxford University and others, has indicated, however, that the hybridisation theory is probably false. Instead, it appears that a single species still growing in the Ili Valley on the northern slopes of the Tien Shan mountains at the border of northwest China and the former Soviet Republic of Kazakhstan is the progenitor of the apples we eat today. Leaves taken from trees in this area were analyzed for DNA composition, which showed them all to belong to the species M. sieversii, with some genetic sequences common to M. domestica.
Some individual M. sieversii, recently planted by the US government at a research facility, r
esist many diseases and pests that affect domestic apples, and are the subject of continuing research to develop new disease-resistant apples.
Other species that were previously thought to have made contributions to the genome of the domestic apples are Malus baccata and Malus sylvestris, but there is no hard evidence for this in older apple cultivars. These and other Malus species have been used in some recent breeding programmes to develop apples suitable for growing in climates unsuitable for M. domestica, mainly for increased cold tolerance.
Apple cut horizontally, showing seedsThe apple tree was probably the earliest tree to be cultivated, and apples have remained an important food in all cooler climates. To a greater degree than other tree fruit, except possibly citrus, apples store for months while still retaining much of their nutritive value. Winter apples, picked in late autumn and stored just above freezing, have been an important food in Asia and Europe for millennia, as well as in Argentina and in the United States since the arrival of Europeans.
The word apple comes from the Old English word aeppel, which in turn has recognisable cognates in a number of the northern branches of the Indo-European language family. The prevailing theory is that "apple" may be one of the most ancient Indo-European words (*abl-) to come down to English in a recognisable form. The scientific name malus, on the other hand, comes from the Latin word for apple, and ultimately from the archaic Greek mālon (mēlon in later dialects). The legendary placename Avalon is thought to come from a Celtic evolution of the same root as the English "apple"; the name of the town of Avellino, near Naples in Italy is likewise thought to come from the same root via the Italic languages.
橘子:
Orange—specifically, sweet orange—refers to the citrus tree Citrus sinensis and its fruit. The orange is a hybrid of ancient cultivated origin, possibly between pomelo (Citrus maxima) and tangerine (Citrus reticulata). It is a small tree, growing to about 10 m tall, with thorny shoots and evergreen leaves 4-10 cm long. Oranges originated in southeast Asia, in either India or modern day Pakistan, Vietnam or southern China. The fruit of Citrus sinensis is called sweet orange to distinguish it from Citrus aurantium, the bitter orange.archaic
Oranges are widely grown in warm climates worldwide, and the flavors of orange vary from sweet to sour. The fruit is commonly peeled and eaten fresh, or squeezed for its juice. It has a thick bitter rind that is usually discarded, but can be processed into animal feed by removing water using pressure and heat. It is also used in certain recipes as flavoring or a garnish. The outer-most layer of the rind is grated or thinly veneered with a tool called a zester, to produce orange zest, popular in cooking because it has a flavor similar to the fleshy inner part of the orange. The white part of the rind, called the pericarp or pith, is a source of pectin.
桃子：
The Peach (Prunus persica) is a tree native to China that bears a juicy fruit of the same name. It is a small deciduous tree growing to 5–10 m tall. The leaves are lanceolate, 7–15 cm long and 2–3 cm broad. The flowers are produced in early spring before the leaves; they are solitary or paired, 2.5–3 cm diameter, pink, with five petals. The fruit is a drupe, with a single large seed encased in hard wood (called the "stone" or "pit"), yellow or whitish
flesh, a delicate aroma, and a velvety skin. Peaches, along with cherries, plums and apricots, are stone fruits (drupes).

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