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''Nerine'' 〔''Sunset Western Garden Book,'' 1995:606–607〕 is a genus of flowering plants belonging to the Amaryllidaceae family, subfamily Amaryllidoideae. They are bulbous perennials, some evergreen, associated with rocky and arid habitats. They bear spherical umbels of lily-like flowers in shades from white through pink to crimson. In the case of deciduous species, the flowers may appear on naked stems before the leaves develop.〔 Native to South Africa,〔 there are about 30 species in the genus. Though described as lilies, they are not significantly related to the true lilies ''Lilium'', but more closely resemble their relatives, ''Amaryllis'' and ''Lycoris''. The genus was established by the cleric and Amaryllidaceae specialist William Herbert in 1820. Nerines have been widely cultivated and much hybridized worldwide, especially ''Nerine bowdenii'', ''N. sarniensis'' and ''N. undulata'' (previously known as ''N. flexuosa''). The hybrid cultivar 'Zeal Giant' has gained the Royal Horticultural Society's Award of Garden Merit.〔(【引用サイトリンク】url=http://apps.rhs.org.uk/plantselector/plant?plantid=3629 )〕 The other 20 species are rarely cultivated and very little is known regarding their biology. Many species are threatened with extinction due to the loss or degradation of their habitat. == Description == Species of ''Nerine'' are herbaceous flowering plants that grow from bulbs. Their leaves are linear, obviously flat in some species and appearing threadlike in others. Their flowers are borne in an umbel on a solid leafless stem (scape). Individual flowers are either radially symmetrical (actinomorphic) or have one plane of symmetry (zygomorphic). Each flower has six narrow red or pink tepals joined at the base to form a short extended or recurved tube. The free parts of the tepals are generally wavy. There are six stamens that are inserted in the base of the petals and frequently protrude from the flower. The stamens can be straight or curved with thin filaments and oblong anthers that attach to their filament at the back (dorsifixed). The inferior ovary has one to many ovules. The style is threadlike and has a three-lobed stigma. The fruit is a capsule.〔 ''Nerine'' species can be either evergreen or deciduous; the deciduous species can either grow during the winter or the summer. The growth cycle thus defines three groups. There is a strong association between a species' growth habit, the shape of its leaves and the amount of DNA in its cell nuclei. The largest group of 12 species contains the evergreen nerines that retain their leaves throughout the summer and winter (''N. angustifolia, N. appendiculata, N. filamentosa, N. filifolia, N. frithii, N. gaberonensis, N. gibsonii, N. gracilis, N. masoniorum, N. pancratioides, N. platypetala'' and ''N. rehmannii''). Their leaves are narrow and they have the smallest amount of DNA per nucleus (18.0–24.6 pg). Four deciduous species grow in the winter and do not have any leaves during the summer (''N. humilis'', ''N. pudica'', ''N. ridleyi'' and ''N. sarniensis''). They have wide leaves and more DNA per nucleus (25.3–26.2 pg). A final group of seven species only grow during the summer and have no leaves in the winter (''N. bowdenii, N. duparquetiana, N. krigei, N. laticoma, N. marincowitzii, N. pusilla'' and ''N. undulata''). They have wide leaves and the most DNA per nucleus (26.8–35.3 pg).〔Goldblatt P. 1972. Chromosome cytology in relation to classification in ''Nerine'' and ''Brunsvigia'' (Amaryllidaceae). J. S. African Bot. 38: 261-275.〕 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「Nerine」の詳細全文を読む スポンサード リンク
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