栏目

太白杜鹃Rhododendron purdomii Rehd. et Wils.

太白杜鹃Rhododendron purdomii Rehd. et Wils.

别名:金背枇杷;药枇杷;秦岭杜鹃;

科名:杜鹃花科 Ericaceae

属名:杜鹃属 Rhododendron

《中国植物志》第57(1)卷116页
  100. 太白杜鹃(植物研究)
  Rhododendron taibaiense Ching et H. P. Yang in Bull. Bot. Res. 3(2): 88. Pl. 1, 1-5. 1983.
  矮小平卧状灌木,高约20-30厘米,分枝极多。当年生枝直径约1毫米,黄褐色,被盾状、锈色、后变黑色随树皮脱落的鳞片。叶聚生于枝端,革质,长圆形或宽椭圆形,长10-25毫米,宽5-10毫米,顶端圆形,具角质突尖,边缘稍反卷,基部钝,上面暗绿色,被同色的鳞片,红玉色,有光泽,几邻接,下面灰黄棕色,鳞片盾状,二色,淡黄色和棕褐色的鳞片几相等混生,稍不邻接;叶柄长0.8-1毫米,被鳞片。伞形花序顶生,具花2-3朵,密聚;花梗长约2毫米;花萼长3.5-4毫米,裂片5,等长,长圆形,外面中部密被鳞片,被长缘毛;花冠漏斗状,长约16毫米,淡紫色,花管长4-5毫米,内面喉部被短毛;雄蕊10,较花冠短,花丝紫色,基部以上达花冠喉部被白色长柔毛;子房长2-3毫米,疏被鳞片,花柱长14-20毫米,较花冠长,无毛。蒴果卵圆形,长3-4毫米。花期7-8月,果期8-9月。
  产陕西中部。生于高山坡及近山颠处,海拔3 000米。模式标本采自太白山。
形态特征:矮小平卧状灌木,高约20—30厘米,分枝极多。当年生枝直径约1毫米,黄褐色, 被盾状、锈色、后变黑色随树皮脱落的鳞片。叶聚生于枝端,革质,长圆形或宽椭圆 形,长10--25毫米,宽5—10毫米,顶端圆形,具角质突尖,边缘稍反卷,基部钝, 上面暗绿色,被同色的鳞片,红玉色,有光泽,几邻接,下面灰黄棕色,鳞片盾状,二 色,淡黄色和棕褐色的鳞片几相等混生,稍不邻接;叶柄长0.8—1毫米,被鳞片。伞 形花序顶生,具花1—3朵,密聚;花梗长约2毫米;花萼长3.5--4毫米,裂片5,等 长,长圆形,外面中部密被鳞片,被长缘毛;花冠漏斗状,长约16毫米,淡紫色,花管长4—5毫米,内面喉部被短毛;雄蕊10,较花冠短,花丝紫色,基部以上达花冠喉部被白色长柔毛;子房长2—3毫米,疏被鳞片,花柱长14—20毫米,较花冠长,无毛。蒴果卵圆形,长3—4毫米。 花期7—8月,果期8---9月。
产地分布:产陕西中部。生于高山坡及近山颠处,海拔3 000米。模式标本采自太白山。
参考文献:Rhododendron taibaiense Ching et H.P.Yang in Bull.Eot.Res.3(2):88.Pl. 1, 1—5.1983.
亚组概述:Subseet.Lapponica(Balf.F.)Sleumer in Bot.Jahrb.74:535.1949.--Ser.Lapponicum Ball.F,in Not.1zk)t.Gard.Edinb.9:298.1916.——Set.Parvifolia Busch in Pl.URSS 18:44.1952,pro parte--Ser.BurjaticaMalysehewinNot.Syst.Herb.Inst.Pot.Akad.Sci.URSS 2l:455.1961.--Sect.Lapponica(Ball.F.)Philipson et M.N.Philipson in Not.Bot.Gard.Edinb.34:25.1975.---Sect.Setosa Philipson et M.N.Philipson in ibid.34:3.1975.常绿小灌木,分枝密集,常缠结成垫状。叶小型,下面表皮细胞具有脊状纹的乳突,鳞片密集或稍有间距,同色或二色,具有宽而波状的边缘。花序顶生,1至数朵花组成伞形总状花序;花梗短;萼明显5裂;花冠漏斗状;雄蕊5—10;子房5室,被鳞片。蒴果短小。种于无翅,有不明显的鳍状物。 亚组的模式种:高山杜鹃Rhododendron lapponicum (L.) Wahl. 本亚组共有40种,除一种分布于东北地区和内蒙古,少数产于陕西、甘肃、青海 外,其余均集中分布于四川、云南及西藏的山区;北半球寒带及高山地带也有间断分 布。我国有39种。

《Flora of China》 Vol. 14 (2005)
Rhododendron purdomii  Rehder & E. H. Wilson
太白杜鹃   tai bai du juan
Shrubs or small trees, 2–6 m tall; young shoots puberulent; bud scales ± persistent. Petiole 10–15 mm, puberulent, glabrescent; leaf blade leathery, oblong-lanceolate to oblong-elliptic, 6–9 × 2.5–3.5 cm; base cuneate; margin revolute; apex obtuse, mucronate; both surfaces glabrous; abaxial surface pale green; reticulate veins distinct. Inflorescence racemose-umbellate, 10–15-flowered; rachis ca. 10 mm, pale brown-tomentose. Pedicel 1–1.5 cm, densely whitish gray-pubescent; calyx lobes 5, 1–1.5 mm, broadly triangular, sparsely pubescent; corolla campanulate, pale pink or whitish, with purple spots on corolla tube on upper lobes, 2.5–3 cm, lobes 5; stamens 10, unequal, filaments densely puberulent in lower half; ovary conical, 4–5 mm, sparsely white-pubescent; style ca. 2.2 cm, glabrous, stigma capitate. Capsule cylindric, slightly curved, 10–30 × 4–8 mm. Fl. May–Jun, fr. Jul–Sep.
Forests, mountain slopes; 1800–3500 m. S Gansu, W Henan, S Shaanxi.
This species almost certainly does not belong in Rhododendron subsect. Taliensia; it probably has closer affinities with species in R. subsect. Selensia. In addition, R. purdomii var. villosum L. H. Wu (J. Wuhan Bot. Res. 17(1): 21. 1999), described from W Henan (Songxian), needs to be considered. It was described as differing from var. purdomii in having the leaf blade larger, 4–11 × 2–5.5 cm, adaxially sparsely yellowish villous, the margin densely ciliate, with both villi and ciliae readily deciduous; the petiole longer, to 3 cm; and the inflorescence rachis longer, to 1.8 cm.

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