13. Rheum palmatum Linnaeus, Syst. Nat., ed. 10. 2: 1010. 1759. 掌叶大黄 zhang ye da huang Rheum palmatumCredit: Harvard University Herbaria Rheum potaninii Losinskaja; R. qinlingense Y. K. Yang et al.Herbs large, 1.5-2 m tall, stout. Rhizomes and roots stout. Stem hollow, sulcate, subglabrous or muricate on nodes. Petiole of basal leaf terete, ca. as long as blade, densely papilliferous; leaf blade large, ca. as long as wide, 40-60 cm, abaxially densely pubescent, adaxially sulcate to papilliferous, basal veins 5, base cordate, palmately divided into pinnatisect lobes, apex acuminate or narrowly acute. Stem leaves smaller above; ocrea large, to 15 cm, outside muricate. Panicle large; branches connivent, densely pubescent. Pedicel 2-2.5 mm, jointed below middle. Flowers small. Tepals 6, purple-red, rarely yellow-white, outer 3 elliptic to orbicular, smaller, 1-1.5 mm. Stamens not exceeding perianth. Ovary rhomboid-ovoid; style slightly deflexed; stigma inflated. Fruit oblong-ellipsoid to oblong, 8-9 × 7-7.5 mm, both ends retuse; wings ca. 2.5 mm wide, with longitudinal veins near margin. Seeds brown-black, broadly ovoid. Fl. Jun, fr. Aug.* Slopes, valleys; 1500-4400 m. Gansu, Hubei, Nei Mongol, Qinghai, Shaanxi, Sichuan, Xizang, Yunnan [cultivated in Russia].The roots and rhizomes are used medicinally.【引自:Flora of China】
高大粗壮草本,高1.5-2米,根及根状茎粗壮木质。茎直立中空,叶片长宽近相等,长达40-60厘米,有时长稍大于宽,顶端窄渐尖或窄急尖,基部近心形,通常成掌状半5裂,每一大裂片又分为近羽状的窄三角形小裂片,基出脉多为5条,叶上面粗糙到具乳突状毛,下面及边缘密被短毛;叶柄粗壮,圆柱状,与叶片近等长,密被锈乳突状毛;茎生叶向上渐小,柄亦渐短;托叶鞘大,长达15厘米,内面光滑,外表粗糙。大型圆锥花序,分枝较聚拢,密被粗糙短毛;花小, 通常为紫红色,有时黄白色;花梗长2-2.5毫米,关节位于中部以下;花被片6, 外轮3片较窄小,内轮3片较大,宽椭圆形到近圆形,长1-1.5毫米;雄蕊9, 不外露;花盘薄,与花丝基部粘连;子房菱状宽卵形,花柱略反曲,柱头头状。果实矩圆状椭圆形到矩圆形,长8-9毫米,宽7-7.5毫米,两端均下凹,翅宽约2.5毫米,纵脉靠近翅的边缘。种子宽卵形,棕黑色。花期6月,果期8月。果期果序的分枝直而聚拢。
【引自:中国植物志】