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''Gunnera'' is a genus of herbaceous flowering plants, the only member of the family Gunneraceae. Some species have extremely large leaves. It is native to Latin America, Australia, New Zealand, Papuasia, Hawaii, insular Southeast Asia, Africa, and Madagascar.〔(Kew World Checklist of Selected Plant Families )〕 ==Description== The 40–50 species vary enormously in leaf size. The Giant Rhubarb, or Campos des Loges (''Gunnera manicata''), native to the Serra do Mar mountains of southeastern Brazil, is perhaps the largest species, with leaves typically long, not including the thick, succulent leaf stalk (petiole) of up to in length. The width is typically , but on two separate occasions cultivated specimens (In Berkeshire, England in 2011 and at Narrowwater, Ulster, Ireland〔The Garden (London) Vol. 63 # 1631 (February 21, 1903) p. 125.〕 in 1903) produced leaves fully in width, making these leaves quite probably the largest of all dicot leaves. The seeds germinate best in very moist, but not wet, conditions and temperatures of 22–29 °C. Only slightly smaller is ''G. masafuerae'' of the Juan Fernandez Islands off the Chilean coast. They can have leaves up to in width on stout leaf stalks long and thick according to Skottsberg.〔Dr Carl Skottsberg, , "The Phanerogams of Juan Fernandez Islands", NATURAL HISTORY OF JUAN FERNANDEZ AND EASTER ISLAND (Uppsala: Almqvist & Wiksells Buktrykeri A.S., 1953) Vol. 2 p.151.〕 On nearby Isla Más Afuera, ''G. peltata'' frequently has an upright trunk to in height by thick, bearing leaves up to wide. The Hoja de Pantano (''G. magnifica'') of the Colombian Andes bears the largest leaf buds of any plant; up to long and thick.〔Dr. Harold St. John, "Gunnera the Magnificent - Giant Herb of Colombia", CHICAGO NATURAL HISTORY MUSEUM BULLETIN, Vol. 30 # 1 (January 1959) p. 3 plus photo on front cover.〕 The succulent leaf stalks are up to long. The massive inflorescence of small, reddish flowers is up to long and weighs about 13 kg. Other giant ''Gunnera'' species are found throughout the Neotropics and Hawaii. Several small species are found in New Zealand, notably ''G. albocarpa'', with leaves only 1–2 cm long, and also in South America, with ''G. magellanica'' having leaves 5–9 cm wide on stalks 8–15 cm long. This genus was named after the Norwegian botanist Johann Ernst Gunnerus. ;Species〔 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「Gunnera」の詳細全文を読む スポンサード リンク
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