is one of the most widely cultivated fruit. Its scientific name is Malus domestica
and it comes from the rose family Rosaceae.
The apple tree is small and deciduous. It reaches a height of 3 to 12 metres (9.8 to 39 ft) tall, and has a broad, often densely twiggy crown. The leaves are alternately arranged in simple ovals. They are 5 to 12 cm long and 3-6 centimetres (1.2-2.4 in) broad on a 2 to 5 centimetres (0.79 to 2.0 in) petiole with an acute tip, serrated margin and a slightly downy underside. Apple blossoms are produced in spring simultaneously with the budding of the leaves. The flowers are white with a pink tinge that gradually fades. They have five petals, and are 2.5 to 3.5 centimetres (0.98 to 1.4 in) in diameter. The fruit matures in autumn, and is typically 5 to 9 centimetres (2.0 to 3.5 in) diameter. The center of the fruit contains five carpels arranged in a five-point star, each carpel containing one to three seeds.
Apple trees originated from Central Asia, where its wild ancestor is still found today. There are more than 7,500 known cultivars of apples resulting in a wide range of characteristics. Cultivars vary in their yield and the ultimate size of the tree, even when grown on the same rootstock.
At least 55 million tonnes of apples were grown worldwide in 2005, with a value of about $10 billion. The biggest producer is China, which produces about 35% of this total. The United States is the second leading producer, with more than 7.5% of the world production. Turkey, France, Italy, and Iran are also among the leading apple exporters.
Apples usually propagate asexually by grafting. Seedling apples are often radically different from their parent plants, and do not inherit the DNA from their parents to create a new apple with those characteristics. 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.
Commercially, apples can be stored for some months in controlled-atmosphere chambers to delay ethylene-induced onset of ripening. Ripening begins when the fruit is removed. For home storage, most varieties of apple can be stored for approximately two weeks, when kept at the coolest part of the refrigerator (i.e. below 5°C). Some types of apple, including the Granny Smith and Fuji, have an even longer shelf life.