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''Cucurbita'' (Latin for gourd)〔 is a genus of herbaceous vine in the gourd family, Cucurbitaceae, also known as cucurbits, native to the Andes and Mesoamerica. Five species are grown worldwide for their edible fruit, variously known as squash, pumpkin, or gourd depending on species, variety, and local parlance, and for their seeds. First cultivated in the Americas before being brought to Europe by returning explorers after their discovery of the New World, plants in the genus ''Cucurbita'' are important sources of human food and oil. Other kinds of gourd, also called bottle-gourds, are native to Africa and belong to the genus ''Lagenaria'', which is in the same family and subfamily as ''Cucurbita'' but in a different tribe. These other gourds are used as utensils or vessels, and their young fruits are eaten much like those of Cucurbita species. Most ''Cucurbita'' species are herbaceous vines that grow several meters in length and have tendrils, but non-vining "bush" cultivars of ''C. pepo'' and ''C. maxima'' have also been developed. The yellow or orange flowers on a ''Cucurbita'' plant are of two types: female and male. The female flowers produce the fruit and the male flowers produce pollen. Many North and Central American species are visited by specialist bee pollinators, but other insects with more general feeding habits, such as honey bees, also visit. The fruits of the genus ''Cucurbita'' are good sources of several nutrients such as vitamin A, vitamin C, niacin, folic acid, and iron, and like all plant products are free of cholesterol. The plants contain the toxins cucurbitin, cucurmosin, and cucurbitacin. There is some disagreement about how to handle the taxonomy of the genus; the number of species accepted by different specialists varies from 13 to 30. In addition, the ancestry of some of the species that have been cultivated for millennia is uncertain. The five domesticated species are ''Cucurbita argyrosperma'', ''C. ficifolia'', ''C. maxima'', ''C. moschata'', and ''C. pepo''. All of these can be treated as winter squash because the full-grown fruits can be stored for months; however, ''C. pepo'' includes some cultivars that are better used only as summer squash. ''Cucurbita'' fruits have played a role in human culture for at least 2,000 years. They are often represented in Moche ceramics from Peru. After Christopher Columbus's arrival in the New World, paintings of squashes started to appear in Europe early in the sixteenth century. Among other uses, extracts are used in cosmetics for dry and sensitive skin. The fruits have many culinary uses including pumpkin pie, biscuits, bread, desserts, puddings, beverages, and soups. Pumpkins and other ''Cucurbita'' fruits are celebrated in festivals and in flower and vegetable shows in many countries. ==Description== ''Cucurbita'' species fall into two main groups. The first group are annual or short-lived perennial vines and are mesophytic, i.e. they require a more or less continuous water supply. The second group are perennials growing in arid zones and so are xerophytic, tolerating dry conditions. Cultivated ''Cucurbita'' species were derived from the first group. Growing in height or length, the plant stem produces tendrils to help it climb adjacent plants and structures or extend along the ground. Most species do not readily root from the nodes; a notable exception is ''C. ficifolia'', and the four other cultivated mesophytes do this to a lesser extent. The vine of the perennial ''Cucurbita'' can become semiwoody if left to grow. There is wide variation in size, shape, and color among ''Cucurbita'' fruits, and even within a single species. ''C. ficifolia'' is an exception, being highly uniform in appearance. The morphological variation in the species ''C. pepo'' and ''C. maxima'' is so vast that its various subspecies and cultivars have been misidentified as totally separate species.〔 The typical cultivated ''Cucurbita'' species has five-lobed or palmately divided leaves with long petioles, with the leaves alternately arranged on the stem. The stems in some species are angular. All of the above-ground parts may be hairy with various types of trichomes, which are often hardened and sharp. Spring-like tendrils grow from each node and are branching in some species. ''C. argyrosperma'' has ovate-cordate (egg-shaped to heart-shaped) leaves. The shape of ''C. pepo'' leaves varies widely. ''C. moschata'' plants can have light or dense pubescence. ''C. ficifolia'' leaves are slightly angular and have light pubescence. The leaves of all four of these species may or may not have white spots.〔 There are male (staminate) and female (pistillate) flowers (unisexual flowers) on a single plant (monoecious), and these grow singly, appearing from the leaf axils. Flowers have five fused yellow to orange petals (the corolla) and a green bell-shaped calyx. Male flowers in Cucurbitaceae generally have five stamens, but in ''Cucurbita'' there are only three, and their anthers are joined together so that there appears to be one. Female flowers have thick pedicels, and an inferior ovary with 3–5 stigmas that each have two lobes.〔〔 The female flowers of ''C. argyrosperma'' and ''C. ficifolia'' have larger corollas than the male flowers.〔 Female flowers of ''C. pepo'' have a small calyx, but the calyx of ''C. moschata'' male flowers is comparatively short.〔 ''Cucurbita'' fruits are large and fleshy.〔 Botanists classify the ''Cucurbita'' fruit as a pepo, which is a special type of berry derived from an inferior ovary, with a thick outer wall or rind with hypanthium tissue forming an exocarp around the ovary, and a fleshy interior composed of mesocarp and endocarp. The term "pepo" is used primarily for Cucurbitaceae fruits, where this fruit type is common, but the fruits of ''Passiflora'' and ''Carica'' are sometimes also pepos.〔(【引用サイトリンク】title=A Systematic Treatment of Fruit Types )〕 The seeds, which are attached to the ovary wall (parietal placentation) and not to the center, are large and fairly flat with a large embryo that consists almost entirely of two cotyledons.〔 Fruit size varies considerably: wild fruit specimens can be as small as and some domesticated specimens can weigh well over .〔 The current world record was set in October 2014 by John Hawkley of Napa County, California with a pumpkin. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cucurbita」の詳細全文を読む スポンサード リンク
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