In botany, the ripened ovary in flowering plants that develops from one or more seeds or carpels and encloses one or more seeds. Its function is to protect the seeds during their development and to aid in their dispersal. Fruits are often edible, sweet, juicy, and colourful. When eaten they provide vitamins, minerals, and enzymes, but little protein. Most fruits are borne by perennial plants.
Fruits are divided into three agricultural categories on the basis of the climate in which they grow. Temperate fruits
require a cold season for satisfactory growth; the principal temperate fruits are apples, pears, plums, peaches, apricots, cherries, and soft fruits, such as strawberries. Subtropical fruits
require warm conditions but can survive light frosts; they include oranges and other citrus fruits, dates, pomegranates, and avocados. Tropical fruits
cannot tolerate temperatures that drop close to freezing point; they include bananas, mangoes, pineapples, papayas, and litchis. Fruits can also be divided botanically into dry
(such as the capsule
, pod or legume, lomentum, and achene
) and those that become fleshy
(such as the drupe
and the berry
). The fruit structure consists of the pericarp
or fruit wall, which is usually divided into a number of distinct layers. Sometimes parts other than the ovary are incorporated into the fruit structure, resulting in a false fruit or pseudocarp
, such as the apple and strawberry. True fruits include the tomato, orange, melon, and banana. Fruits may be dehiscent, which open to shed their seeds, or indehiscent, which remain unopened and are dispersed as a single unit. Simple fruits (for example, peaches) are derived from a single ovary, whereas compositae or multiple fruits (for example, blackberries) are formed from the ovaries of a number of flowers. In ordinary usage, fruit includes only sweet, fleshy items; it excludes many botanical fruits such as acorns, bean pods, thistledown, and cucumbers.
Methods of seed dispersal
Efficient seed dispersal is essential to avoid overcrowding and enable plants to colonize new areas; the natural function of a fruit is to aid in the dissemination of the seeds which it contains. A great variety of dispersal mechanisms exist: winged fruits are commonly formed by trees, such as ash and elm, where they are in an ideal position to be carried away by the wind; some wind-dispersed fruits, such as clematis and cotton, have plumes of hairs; others are extremely light, like the poppy, in which the capsule acts like a pepperpot and shakes out the seeds as it is blown about by the wind. Some fruits float on water; the coconut can be dispersed across oceans by means of its buoyant fruit. Geraniums, gorse, and squirting cucumbers have explosive mechanisms, by which seeds are forcibly shot out at dehiscence. Animals often act as dispersal agents either by carrying hooked or sticky fruits (burs) attached to their bodies, or by eating succulent fruits, the seeds passing through the alimentary canal unharmed.
Recorded world fruit production in the mid-1980s was approximately 300 million tonnes per year. Technical advances in storage and transport have made tropical fruits available to consumers in temperate areas, and fresh temperate fruits available all year in major markets.
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