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The Solanaceae, or nightshades, are an economically important family of flowering plants. The family ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs, and trees, and includes a number of important agricultural crops, medicinal plants, spices, weeds, and ornamentals. Many members of the family contain potent alkaloids, and some are highly toxic, but many cultures eat nightshades, in some cases as staple foods. The family belongs to the order Solanales, in the asterid group dicotyledons (Magnoliopsida). The Solanaceae consists of about 98 genera and some 2,700 species, with a great diversity of habitats, morphology and ecology. The name Solanaceae derives from the genus ''Solanum'', "the nightshade plant". The etymology of the Latin word is unclear. The name may come from a perceived resemblance of certain solanaceous flowers to the sun and its rays. At least one species of ''Solanum'' is known as the "sunberry". Alternatively, the name could originate from the Latin verb ''solari'', meaning "to soothe", presumably referring to the soothing pharmacological properties of some of the psychoactive species of the family. The family has a worldwide distribution, being present on all continents except Antarctica. The greatest diversity in species is found in South America and Central America. The Solanaceae include a number of commonly collected or cultivated species. The most economically important genus of the family is ''Solanum'', which contains the potato (''S. tuberosum'', in fact, another common name of the family is the "potato family"), the tomato (''S. lycopersicum''), and the eggplant or aubergine (''S. melongena''). Another important genus, ''Capsicum'', produces both chili peppers and bell peppers. The genus ''Physalis'' produces the so-called groundcherries, as well as the tomatillo (''Physalis philadelphica''), the Cape gooseberry and the Chinese lantern. The genus ''Lycium'' contains the boxthorns and the wolfberry ''Lycium barbarum''. ''Nicotiana'' contains, among other species, tobacco. Some other important members of Solanaceae include a number of ornamental plants such as ''Petunia'', ''Browallia'', and ''Lycianthes'', the source of psychoactive alkaloids, ''Datura'', ''Mandragora'' (mandrake), and ''Atropa belladonna'' (deadly nightshade). Certain species are widely known for their medicinal uses, their psychotropic effects, or for being poisonous. Most of the economically important genera are contained in the subfamily Solanoideae, with the exceptions of tobacco (''Nicotiana tabacum'', Nicotianoideae) and petunia (''Petunia x hybrida'', Petunioideae), Many of the Solanaceae, such as tobacco and petunia, are used as model organisms in the investigation of fundamental biological questions at the cellular, molecular, and genetic levels. == Description == Plants in the "Solanaceae" can take the form of herbs, shrubs, trees, vines and lianas, and sometimes epiphytes. They can be annuals, biennials, or perennials, upright or decumbent. Some have subterranean tubers. They do not have laticifers, nor latex, nor coloured saps. They can have a basal or terminal group of leaves or neither of these types. The leaves are generally alternate or alternate to opposed (that is, alternate at the base of the plant and opposed towards the inflorescence). The leaves can be herbaceous, leathery, or transformed into spines. The leaves are generally petiolate or subsessile, rarely sessile. They are frequently inodorous, but on occasions, they are aromatic or fetid. The foliar lamina can be either simple or compound, and the latter can be either pinnatifid or ternate. The leaves have reticulated venation and lack a basal meristem. The laminae are generally dorsiventral and lack secretory cavities. The stomata are generally confined to one of a leaf's two sides; they are rarely found on both sides. The flowers are generally hermaphrodites, although some are monoecious, andromonoecious, or dioecious species (such as some ''Solanum'' or ''Symonanthus''). Pollination is entomophilous. The flowers can be solitary or grouped into terminal, cymose, or axillary inflorescences. The flowers are medium-sized, fragrant (''Nicotiana''), fetid (''Anthocercis''), or inodorous. The flowers are usually actinomorphic, slightly zygomorphic, or markedly zygomorphic (for example, in flowers with a bilabial corolla in ''Schizanthus'' species). The irregularities in symmetry can be due to the androecium, to the perianth, or both at the same time. In the great majority of species, the flowers have a differentiated perianth with a calyx and corolla (with five sepals and five petals, respectively) an androecium with five stamens and two carpels forming a gynoecium with a superior ovary〔(【引用サイトリンク】 Solanaceae )〕 (they are therefore referred to as pentamers and tetracyclic). The stamens are epipetalous and are typically present in multiples of four or five, most commonly four or eight. They usually have a hypogynous disk. The calyx is gamosepalous (as the sepals are joined together forming a tube), with the (4)5(6) segments equal, it has five lobes, with the lobes shorter than the tube, it is persistent and often accrescent. The corolla usually has five petals that are also joined together forming a tube. Flower shapes are typically rotate (wheel-shaped, spreading in one plane, with a short tube) or tubular (elongated cylindrical tube), campanulated or funnel-shaped. The androecium has (2)(4)5(6) free stamens within it, oppositsepals (that is, they alternate with the petals), they are usually fertile or, in some cases (for example in Salpiglossideae) they have staminodes. In the latter case, there is usually either one staminode (''Salpiglossis'') or three (''Schizanthus''). The anthers touch on their upper end forming a ring, or they are completely free, dorsifixed, or basifixed with poricide dehiscence or through small longitudinal cracks. The stamen’s filament can be filliform or flat. The stamens can be inserted inside the coralline tube or exserted. The plants demonstrate simultaneous microsporogenesis, the microspores are tetrad, tetrahedral, or isobilateral. The pollen grains are bicellular at the moment of dehiscence, usually open and angular. The gynoecium is bicarpelar (rarely three- or five-locular) with a superior ovary and two locules, which may be secondarily divided by false septa, as is the case for Nicandreae and Datureae. The gynoecium is located in an oblique position relative to the flower’s median plane. They have one style and one stigma; the latter is simple or bilobate. Each locule has one to 50 ovules that are anatropous or hemianatropous with axillar placentation. The development of the embryo sack can be the same as for ''Polygonum'' or ''Allium'' species. The embryo sack’s nuclear poles become fused before fertilization. The three antipodes are usually ephemeral or persistent as in the case of ''Atropa''. The fruit can be a berry as in the case of the tomato or wolfberry] a dehiscent capsule as in ''Datura'', or a drupe. The fruit has axial placentation. The capsules are normally septicidal or rarely loculicidal or valvate. The seeds are usually endospermic, oily (rarely starchy), and without obvious hairs. The seeds of most Solanaceae are round and flat, about in diameter. The embryo can be straight or curved, and has two cotyledons. Most species in the Solanaceae have 2n=24 chromosomes, but the number may be a higher multiple of 12 due to polyploidy. Wild potatoes, of which there are about 200, are predominantly diploid (2 × 12 = 24 chromosomes), but triploid (3 × 12 = 36 chromosomes), tetraploid (4 × 12 = 48 chromosomes), pentaploid (5 × 12 = 60) and even hexaploid (6 × 12 = 72 chromosome) species or populations exist. The cultivated species ''Solanum tuberosum'' has 4 × 12 = 48 chromosomes. Some ''Capsicum'' species have 2 × 12 = 24 chromosomes, while others have 26 chromosomes. 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「Solanaceae」の詳細全文を読む スポンサード リンク
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