词条 | fruit |
释义 | fruit plant reproductive body ![]() ![]() ![]() A fruit is a mature ovary and its associated parts. It usually contains seeds, which have developed from the enclosed ovule after fertilization, although development without fertilization, called parthenocarpy, is known, for example, in bananas. The principal botanical purpose of the fruit is the protection and dissemination of the seed. Fertilization induces various changes in a flower: the anthers and stigma wither, the petals drop off, and the sepals may be shed or undergo modifications; the ovary enlarges, and the ovules develop into seeds, each containing an embryo plant. (See also seed (seed and fruit).) There are two broad categories of fruits: fleshy fruits, in which the pericarp and accessory parts develop into succulent tissues, as in tomatoes, oranges, and cherries; and dry fruit, in which the entire pericarp becomes dry at maturity. Fleshy fruits include (1) the berries (berry), such as tomatoes, oranges, and cherries, in which the entire pericarp and the accessory parts are succulent tissue; (2) aggregate fruits, such as blackberries and strawberries, which form from a single flower with many pistils, each of which develops into fruitlets; and (3) multiple fruits, such as pineapples and mulberries, which develop from the mature ovaries of an entire inflorescence. Dry fruits include the legumes, cereal grains, capsulate fruits, and nuts. In general, the chief concerns of fruit cultivation are the propagation and improvement of varieties; the improvement of the microclimatic conditions and soil conditions of the site; the design of planting and spacing systems; the development of training and pruning techniques; soil management, irrigation, and fertilization; pollination; thinning; pest control; and the development of harvesting and postharvest practices. Fruits are important sources of dietary fibre and vitamins (especially vitamin C). Although fresh fruits are subject to spoilage, their shelf life can be extended by refrigeration or by the removal of oxygen from their storage or packaging containers. Fruits can be processed into juices, jams, and jellies and preserved by dehydration, canning, fermentation, and pickling. |
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