- This article is about the fruit; for other meanings of the word, especially the company Apple Computer, see Apple
(disambiguation).
Apple is the fruit (pome) of
the genus Malus belonging to the family Rosaceae, and is the most widely
cultivated tree fruit. Most table apples are of the species M. domestica or hybrids of it.
The wild ancestor of Malus domestica is almost certainly Malus sieversii (which has no common name), a tree
still found wild in the mountains of central Asia in southern Kazakhstan,
Kyrgyzstan, Tajikistan, and
Xinjiang Province, China. Researchers are
working with M. sieversii, which is resistant to many diseases and pests, in order to create hardier and more
disease-resistant domestic 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.
History
Apple blossom
Apples have been a very 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 fall and stored just above freezing in a root cellar or fruit
room have been an important food in Europe and the USA since the 1800s.
Apple cultivars
There are more than 7,500 known cultivars of apples. Cultivars are available for
subarctic, subtropical, and temperate climates. Apples do not flower
in tropical climates because they have a chilling requirement.
The following is a list of common cultivars and where they are grown. The year and place of origin is also listed:
- Braeburn: New Zealand (since 1950s), United States
- Cameo: Washington (since 1980s)
- Cortland:
New York (since late 1890s)
- Cox's Orange Pippin: Britain, New Zealand
- Egremont Russet:
Britain
- Empire: New York
(since 1966)
- Fuji: Japan (since 1930s), Asia, Australia
- Gala: New Zealand (since 1970s), United
States
- Ginger Gold: Virginia (late 1960s)
- Golden Delicious: United States (since 1890), Europe
- Granny Smith: Australia (since 1868), California)
- Honeycrisp: Minnesota (since 1960)
- Idared: Idaho (since 1942)
- Jonagold: New York (since 1968),
elsewhere in United States
- Jonathan: New
York (since 1920s), elsewhere in United States
- McIntosh: Canada (since 1811)
- Newtown Pippin: New York
(since 1759), Oregon
- Pink Lady: Australia (since early
1970s), western United States
- Red Delicious: Iowa (since 1870s), elsewhere in United States
- Rome Beauty: Ohio (since early 1800s)
- Winesap: United States
Granny Smith
Granny Smith is tart; some people eat it fresh and it is popular for cooking. Its skin is a light speckled green. It requires
a long growing season and a hot climate to mature fully, though inferior fruits are grown in unsuitable areas.
A Granny Smith apple is portrayed on the logo of Apple Records, a
record label that publishes music by The Beatles.
Flavors of apples
Tastes in apples vary from one person to another and have changed over time. As an example, the state of Washington (United States) made its reputation for apple growing
on Red Delicious. But in recent years other cultivars have steadily grown in popularity; some Americans have come to regard Red
Delicious as an inferior apple of excessively mild flavor and excessively soft texture. Such people have gravitated toward
crisper apples such Fuji and Gala.
Modern apples are, as a rule, sweeter than older cultivars. Most North
Americans and Europeans favor sweet, subacid apples, but tart apples have a strong minority following. Extremely sweet apples
with barely any acid flavor are popular in Asia. All newly developed apple cultivars are
soft but crisp. Other desired in modern apple breeding are a colorful skin, absence of russeting, ease of shipping, storage
ability, high yields, disease resistance, typical "Washington Red Delicious" apple shape, long stem (to allow pesticides to penetrate the top of the fruit), and acceptable flavor to the average
person. Old cultivars are often oddly shaped, and russeted and have a variety of textures and colors. Many of them have excellent
flavour (often better than most modern cultivars), but may have other problems which make them commercially unviable, such as low
yield, liability to disease, and poor storage tolerance. Few old cultivars are still produced on a large scale, but many have
been kept alive by home gardeners and farmers that sell directly to local markets. Many unusual and locally important cultivars
with their own unique flavor and appearance are out there to discover; apple conservation campaigns have sprung up around the
world to preserve such local heirlooms from extinction.
There are cultivars of apples cultivated specifically for producing cider. Cider apples are typically too tart and astringent to eat out of hand, but they give
the beverage a rich flavor that ordinary eating apples cannot.
Apple breeding
Like most perennial fruits, apples are ordinarily propagated asexually by grafting. Seedling apples differ from their parents, sometimes radically. Most new apple cultivars originate as
seedlings, which either arise by chance or are bred by deliberately crossing cultivars with promising characteristics. The words
seedling, pippin, and kernel in the name of an apple cultivar suggest that it
originated as a seedling. Apples can also form bud sports (mutations on a single branch). Some bud sports turn out to be improved strains of the parent
cultivar. Some differ sufficiently from the parent tree to be considered new cultivars.
Some breeders have crossed ordinary apples with crabapples or unusually hardy
apples in order to produce hardier
cultivars. For example, the Excelsior Experiment Station of the University of Minnesota has, since the 1930s, introduced a
steady progression of important hardy apples that are widely grown, both commercially and by backyard orchardists, throughout
Minnesota and Wisconsin. Its most
important introductions have included Haralson, which is the most widely cultivated apple in Minnesota, Wealthy, Honeygold, and
Honeycrisp. The sweetness and texture of Honeycrisp have been so popular with consumers that Minnesota orchards have been cutting
down their established, productive trees to make room for it, a heretofore unheard of practice.
Growing apples
Apple orchard
Starting an orchard
Apple orchards are established by planting two or three year old trees. These small trees are usually purchased from a
nursery where they are produced by grafting or budding. First, a rootstock is produced either as a
seedling or cloned using tissue culture or layering. This is allowed to grow for a year. Then, a small section of branch called a
scion is obtained from a mature apple tree of the desired cultivar. The upper stem and branches of the rootstock are cut away and
replaced with the scion. In time, the two sections grow together and produce a healthy tree.
Rootstocks affect the ultimate size of the tree. While many rootstocks are available to commercial grower, those sold to
homeowners who want just a few trees are usually one of two cultivars: a standard seedling rootstock that gives a full-size tree,
or a semi-dwarf rootstock that produces a somewhat smaller tree. Dwarf rootstocks are
generally more susceptible to damage from wind and cold. Full dwarf trees are often supported of posts or trellises and planted
in high density orchards which are much simpler to culture and greatly increase productivity per unit of
land.
Some trees are produced with a dwarfing "interstem" between a standard rootstock and the tree, resulting in two grafts.
After the small tree is planted in the orchard, it must grow for 3-5 years (semi-dwarf) or 4-10 years (standard trees) before
it will bear sizable amounts of fruit. Good training of limbs and careful nipping of buds
growing in the wrong places, are extremely important during this time, to build a good scaffold that will later support a fruit
load.
Location
Apples are relatively indifferent to soil conditions and will grow in a wide range of
pH values and fertility levels. They do require some protection from the wind and should not be
planted in low areas that are prone to late spring frosts. Apples do require good
drainage, and heavy soils or flat land should be tiled to make certain that the
root systems are never in saturated soil.
Apples are self-incompatible and must be cross-pollinated. Pollination management is an important component of apple culture. Before planting, it is
important to arrange for pollenizers - cultivars of apple or
crab apple that provide plentiful, viable and compatible pollen. Orchard blocks may alternate rows of compatible cultivars, or
may have periodic crab apple trees, or grafted-on limbs of crab apple. Some cultivars produce very little pollen, or the pollen
is sterile, so these are not good pollenizers. Quality nurseries have pollenizer compatibility lists.
Growers with old orchard blocks of single cultivars sometimes provide bouquets of crab apple blossoms in drums or pails in the
orchard for pollenizers. Home growers with a single tree, and no other cultivars in the neighborhood can do the same on a smaller
scale.
During the bloom each season, apple growers usually provide pollinators to carry the pollen. Honeybee hives are most
commonly used, and arrangements may be made with a commercial beekeeper who supplies hives for a fee. Orchard mason bees are
also used as supplemental pollinators in commercial orchards. Home growers may find these more acceptable in suburban locations
because they do not sting. Some wild bees such as carpenter bees and
other solitary bees may help.
Bumble bee queens are sometimes present in orchards, but not usually in enough
quantity to be significant pollinators.
Symptoms of inadequate pollination are small and mishapen apples, and slowness to ripen. Count the seeds to evaluate
pollination. Well pollinated apples are the best quality, and will have 7 to 10 seeds. Less than 3 seeds will usually not mature
and will drop from the trees in the early summer. Inadequate pollination can result from either a lack of pollinators or
pollenizers, or from poor pollinating weather at bloom time. It generally require multiple bee visits to deliver sufficient
grains of pollen to accomplish complete pollination.
Frost during bloom
A common problem is a late frost that destroys the delicate outer structures of the flower. It is best to plant apples on a
slope for air drainage, but not on a south facing slope (in the northern hemisphere) as this will encourage early blooming and
increase susceptibilty to frost. If the frost is not too severe, the tree can be wetted with water spray before the morning sun
hits the blossoms, and it may save them. Frost damage can be evaluated 24 hours after the frost. If the pistil has turned black, the blossom is ruined and will not produce fruit.
Growing apples near a body of water gives an advantage by slowing spring warm up, which retards bloom until frost is less
likely. Areas of the USA, such as the eastern shore of Lake Michigan, the
southern shore of Lake Ontario, and around some smaller lakes, where this
cooling effect of water, combined with good, well-drained soils, has made apple growing concentrations possible in these
areas.
Home growers may not have a body of water to help, but can utilize north slopes or other geographical features to retard
spring bloom. Apples (or any fruit) planted on a south facing slope in the US, will bloom early and be particularly vulnerable to
spring frost.
Thinning
Apples are prone to biennial bearing. If the fruit is not thinned when the tree carries a large crop, it may produce
very little bloom the following year. Good thinning helps even out the cycle, so that a reasonable crop can be grown every
year.
Pests & diseases
The trees are susceptible to a number of fungal and bacterial diseases and insect pests. Nearly all commercial orchards
pursue an aggressive program of chemical sprays to maintain high fruit quality, tree health, and high yields. A trend in orchard
management is the use of IPM or Integrated Pest
Management, which reduces needless spraying when pests are not present, or more likely, are being controlled by natural
controls.
Spraying for insect pests must never be done during bloom because it kills pollinators. Nor should bee-attractive plants be
allowed to establish in the orchard floor if insecticides are used. Dutch white clover is a
componant of many grass seed mixes, and many bees are poisoned while visiting the blossoms on the orchard floor.
Among the most serious disease problems are fireblight, a bacterial disease;
and Gymnosporangium rust, apple scab, and black spot, three fungal diseases.
The plum curlico is the most
serious insect pest. Others are apple maggot and codling moth.
Apples are difficult to grow organically, though a few orchards have done so with commercial success, using disease-resistant
cultivars and the very best cultural controls. The latest tool in the organic repertoire is to spray a light coating of kaolin clay, which forms a physical barrier to some pests, and also helps prevent apple sun
scald.
Harvest
Most mature trees typically bear 5-10 bushels (100 to 200 kg) of apples each year.
Apples are harvested using three-point ladders that are designed to fit amongst the branches. A few cultivars, left unpruned,
will grow to be extremely large, causing them to bear a great deal of fruit that it is almost impossible to harvest. Dwarf trees
will bear about 3-5 bushels (50 to 100 kg) of fruit per year.
Cultivars vary in their yield and the ultimate size of the tree, even when grown on the same rootstock.
Commerce
45 million metric tons of apples were grown worldwide in 2002, with a value of about 10 billion USD. China produced almost half of this total. The United
States is the second leading producer, accounting for 10% of world production. Turkey is also a leading producer. France, Italy, South Africa and Chile are among the leading apple exporters.
Today, more than 60% of all the apples sold commercially in the United
States are grown in Washington state. This may change. Imported apples from
New Zealand and other more temperate areas are competing with domestic
production and increasing each year.
Uses
Apples can be canned, juiced, and/or fermented to produce apple juice,
cider, vinegar, and pectin. Distilled apple cider produces the spirits applejack and Calvados.
Apples are an important ingredient in many winter desserts, for example apple pie, apple crumble and apple cake. They are often eaten baked or stewed, and they can also be dried and eaten or
re-consitituted (soaked in water, alcohol or some other liquid) for later use. Pureed apples are generally known as apple sauce. Apples are also made into apple butter and apple jelly. They are also
used cooked in meat dishes.
Cultural aspects
The ancient Kazakh city of Almaty,
'Mother of Apples', owes its name to the forests of wild apples found naturally in the area.
Apples were very important in many ancient cultures, including Norse, Roman and Greek beliefs. See Pleiades and
Idun for examples.
Although the "fruit" in the religious book of Genesis is not identified,
popular European Christian tradition has held that it was an apple that Adam and Eve ate. This tradition was probably solidified by artistic renderings of
the fall from Eden featuring an apple; some kind of fruit had to be pictured and the apple was probably the most familiar fruit
to the artists. The larynx in the human throat has been called Adam's
apple because of a notion that it was caused by the forbidden fruit sticking in the throat of Adam.
In some cultures, the apple is a symbol of immortality, love, or sexuality. The Greek hero Heracles had to find the Hesperides' golden apples as one of his
Twelve Labors. Another Greek mythological figure, Paris, had
to give a golden apple (which came from the goddess of discord, Eris) to the most beautiful
goddess, indirectly causing the Trojan War, while Atalanta was distracted during a race by three golden apples thrown for that purpose by a suitor, Hippomenes. In ancient Greece, throwing an apple at a person's bed was an invitation
for sexual intercourse. Celtic mythology includes a story about Conle who receives an apple which feeds him for a year but also makes him irresistibly desire fairyland. Another story claims that if an apple is peeled into one continuous ribbon and thrown
behind a woman's shoulder, it will land in the shape of the future husband's initials. Danish folklore says that apples wither around adulterers.
In some places, dunking for apples is a traditional Halloween activity. Apples
are said to increase a woman's chances of conception as well as remove birthmarks when rubbed on the skin. They are commonly
considered healthy, leading to the proverb an apple a day keeps the doctor away. In the United States, Denmark and Sweden, an apple is a traditional gift for a teacher.
See also
External links and references
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