林早熟禾
| 林早熟禾 |
 |
|
界：植物界 門：被子植物門 Angiospermae 綱：百合綱 Liliopsida 亞綱：鴨跖草亞綱 Commelinidae 目：莎草目 Cyperales 科：禾本科 Gramineae 亞科：早熟禾亞科 SubFam. Pooideae 屬：早熟禾屬 Poa |
林早熟禾(lín zǎo shú hé)，拉丁文 Poa nemoraliformis Roshevitz，俗名：大序早熟禾，異名：Poa major ，是被子植物門禾本科下早熟禾屬的一個物種，多年生，疏叢。稈直立，高60-90厘米，帶紫褐色，頂節位於稈的1/3以上。葉鞘短於其節間，平滑無毛，基部葉鞘紫色；葉舌長0.5毫米；葉片扁平，寬2-3毫米，上面粗糙。圓錐花序長10-20厘米，疏鬆，分枝下部長裸露，粗糙，1-3枚着生於各節；小穗卵圓形， [1]
目錄
形態特徵
多年生，疏叢。稈直立，高60-90厘米，帶紫褐色，頂節位於稈的1/3以上。葉鞘短於其節間，平滑無毛，基部葉鞘紫色；葉舌長0.5毫米；葉片扁平，寬2-3毫米，上面粗糙。
圓錐花序長10-20厘米，疏鬆，分枝下部長裸露，粗糙，1-3枚着生於各節；小穗卵圓形，含5-7小花，長6-7毫米；穎披針形，先端尖，第一穎長4-4.5毫米，具1或2-3脈，第二穎長4-5.5毫米；
外秤披針形，頂端尖有膜質，脊和邊脈1/3以下具長柔毛，基盤無綿毛，第一外稃長4-4.5毫米；內稃長3.5-4毫米，兩脊具纖毛；花葯紫色，長2-2.5毫米。花期7-9月。
FOC >> Vol.22 (2006) >> Poaceae >> Poa 75.Poa nemoraliformis Roshevitz 林早熟禾 lin zao shu he Poa major D. F. Cui.
Culms loosely to densely tufted, 30–50 cm tall, erect, usually hard, scabrid, nodes 2–5, uppermost in lower 1/3; base covered by withered leaf sheaths. Shoots extravaginal. Leaf sheath scabrid, longer than blade; blade usually flat, later folded or inrolled, 1.5–2.5 mm wide, scabrid; ligule (0.5–)1–1.5 mm. Panicle oblong, conferted, 8–16(–20) cm, branches thin, 2–4.5 cm.
Spikelets elliptic-lanceolate, green or tinged with purple, 4–6(–6.5) mm, florets 3 or 4, usually with upper floret rudimentary; rachilla usually glabrous; glumes oblong-lanceolate, apex acuminate, lower glume ca. 3.5 mm, upper glume 4–4.2 mm, margins dry membranous, keel scabrid; lemma oblong-lanceolate, 3.2–4 mm; margins membranous, keel and marginal veins usually short-villous to glabrous along lower 1/2; callus glabrous. Anthers ca. 2 mm. Fl. Jun–Aug.
Open grasslands on rocky slopes, meadows along forest margins, thickets; 1100–4300 m. Xinjiang, Xizang [India, Tajikistan].
Poa nemoraliformis differs from P. nemoralis in its longer ligule 1–1.5 mm (vs. 0.2–1 mm), glabrous rachilla, and unwebbed lemma callus, and differs from P. versicolor subsp. relaxa in never forming dense tufts. The syntypes represent a sequence of increasing xeromorphism (leaf blades more firm, position of uppermost node varying from 1/2 to 1/3 way up culm). The first two syntypes differ from the description in the protologue in having the rachilla shortly hairy; the second syntype differs in having a long ligule ca. 2.4 mm.
Records of Poa sterilis M. Bieberstein from China are probably based on this species. Examination of the type of P. major has shown that it was misplaced in P. subg. Poa and belongs here.
分類文獻
Poa major D.F. Cui in Acta Bot.Bor.Occ.Sinica 7(2): 83, 圖1.1987; 新疆植物志6: 104, 圖版38: 1-5.1996.
產地生境
產新疆（新源、尼克蘇）。生于山地草甸，海拔2400米。模式標本采自新疆新源。