The rose family (Rosaceae) contains a wide array of fruits grown in the cool regions of the world: apples, pears, plums, peaches, cherries, strawberries, and raspberries. Apples are the most important fruit tree crop of temperate regions. Apple and pear fruits are known as pomes because the edible fleshy part of the fruit is a combination of the outer ovary wall and the basal part of the flower. Cultivated apples are believed to have originated in western Asia and were enjoyed in prehistoric times. Apples were brought to North America about 1620 and are now the most widely grown fruit in the United States. Most of the apples grown today are diploids, but many are triploids. Orchards are usually planted with grafted trees, to ensure uniformity of the crop. Literally thousands of varieties of apples have been developed over the centuries since the species was domesticated.
Plums, peaches, and cherries come from different species of the genus Prunus. They share a fruit type known as a drupe, consisting of a fleshy mesocarp and a single seed inside of a hard endocarp. While there are native species of Prunus in the New World, the domesticated species are native to Eurasia.
The modern cultivated strawberry is a hybrid that apparently formed spontaneously in a European garden between a species of Fragaria from Chile and one from Virginia. Europeans had eaten native strawberries for centuries before the discovery of the New World, but the hybrid (Fragaria ananassa) was larger in size, as flavorful, and produced more fruit. A strawberry is actually an aggregation of fruits, or aggregate fruit. Each tiny seed is itself a fruit. The large, succulent, mass is the swollen top of the stem on which the flower was borne. Raspberries are also aggregated fruits, but each globular segment of the raspberry is itself a fruit, called a drupelet. The caps of drupelets pull free of the stem tips when the berry is picked.
Grapes are the second most widely cultivated fleshy fruit (on a tonnage-produced basis). However, the majority of grapes are not eaten as fruit but are turned into other foods, such as vinegar, liqueurs, raisins, and wine. The most widely cultivated species of grape is Vitis vinifera (Vitaceae), a woody perennial vine native to middle Asia. There are hundreds of varieties of grapes that vary in the color of the skin, flesh, flavor, and sweetness of the berries.
Nuts are dry fruits, each of which contains a single seed that is free inside the ovary wall, except for an attachment at one end called the funiculus. The pericarp (the walls of the ovary) is hard and fibrous. Commercially grown nuts include filberts, pecans, walnuts, and macadamia nuts, sold both for eating and for cooking.
See also: Tropical Fruits
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