<code id="5j9tw"><nobr id="5j9tw"><sub id="5j9tw"></sub></nobr></code>

    1. <object id="5j9tw"></object>
    2. <th id="5j9tw"></th>
    3. <th id="5j9tw"><option id="5j9tw"></option></th>

      <big id="5j9tw"><nobr id="5j9tw"></nobr></big>

          Login Sign Up

          蘇鐵 Cycas revoluta Thunberg

          目前為止,中國西南野生生物種質資源庫共保藏該物種: DNA材料1份;

          • 科:蘇鐵科    Cycadaceae
          • 屬:蘇鐵屬    Cycas
          • 種:蘇鐵   Cycas revoluta

          1志書描述

          6. Cycas revoluta Thunberg, Verh. Holl. Maatsch. Weetensch. Haarlem. 20(2): 424, 426-427. 1782. 蘇鐵 su tie Trunk to 3(-8) m × 45(-95) cm, base and sometimes distal part with numerous adventitious lateral branches or bulbils, apex tomentose; bark gray-black, scaly. Leaves 40-100 or more, 1-pinnate, 0.7-1.4(-1.8) m × 20-25(-28) cm; petiole subtetragonal in cross section, 10-20 cm, with 6-18 spines along each side; leaf blade oblong- or elliptic-lanceolate, strongly "V"-shaped in cross section, recurved, brown tomentose when young; leaflets in 60-150 pairs, horizontally inserted at ca. 45° above rachis, not glaucous when mature, straight to subfalcate, 10-20 cm × 4-7 mm, leathery, sparsely pubescent abaxially, base decurrent, margin strongly recurved, apex acuminate, pungent. Cataphylls triangular, 4-5 × 1.5-2.3 cm, densely brown tomentose, apex acuminate. Pollen cones pale yellow, ovoid-cylindric, 30-60 × 8-15 cm; microsporophylls narrowly cuneate, 3.5-6 × 1.7-2.5 cm, apex rounded-truncate, cuspidate. Megasporophylls yellow to pale brown, 14-22 cm, densely tomentose; stalk 7-12 cm; sterile blade ovate to narrowly so, 6-11 × 4-7 cm, deeply laciniate, with 21-35 lobes 1-3 cm; ovules 2 or 3 on each side of stalk, densely pale brown tomentose. Seeds 2(-5), orange to red, obovoid or ellipsoid, somewhat compressed, (3-)4-5 × 2.5-3.5 cm, sparsely hairy; sclerotesta not grooved on sides. Pollination May-Jul, seed maturity Sep-Oct.Thickets on hillsides on islands, sparse forests on mainland; 100-500 m. Fujian (Lianjiang Xian, Ningde Xian, and some islands) [S Japan (Kyushu, Ryukyu Islands)]A vulnerable, if not endangered, species in China. Its formerly wide distribution in E Fujian has now been severely reduced as a result of over collection by commercial dealers and habitat destruction. It was sporadically distributed in Fujian in the 1960s, but it is now uncertain that any wild populations still exist. Cycas revoluta is the most commonly cultivated cycad because of its ornamental appearance, hardiness, and adaptability.【引自:Flora of China】

          樹干高約2米,稀達8米或更高,圓柱形如有明顯螺旋狀排列的菱形葉柄殘痕。羽狀葉從莖的頂部生出,下層的向下彎,上層的斜上伸展,整個羽狀葉的輪廓呈倒卵狀狹披針形,長75-200厘米,葉軸橫切面四方狀圓形,柄略成四角形,兩側有齒狀刺,水平或略斜上伸展,刺長2-3毫米;羽狀裂片達100對以上,條形,厚革質,堅硬,長9-18厘米,寬4-6毫米,向上斜展微成“V"字形,邊緣顯著地向下反卷,上部微漸窄,先端有刺狀尖頭,基部窄,兩側不對稱,下側下延生長,上面深綠色有光澤,中央微凹,凹槽內有稍隆起的中脈,下面淺綠色,中脈顯著隆起,兩側有疏柔毛或無毛. 雄球花圓柱形,長30-70厘米,徑8-15厘米,有短梗,小孢子飛葉窄楔形,長3.5-6厘米,頂端寬平,其兩角近圓形,寬1.7-2.5厘米,有急尖頭,尖頭長約5毫米,直立,下部漸窄,上面近于龍骨狀,下面中肋及頂端密生黃褐色或灰黃色長絨毛,’花藥通常 3個聚生;大孢子葉長14-22厘米,密生淡黃色或淡灰黃色絨毛,上部的頂片卵形至長卵形,邊緣羽狀分裂,裂片12-18對,條狀鉆形,長2.5-6厘米,先端有刺狀尖頭,胚珠2-6枚,生于大孢子葉柄的兩側,有絨毛。種子紅褐色或桔紅色,倒卵圓形或卵圓形,稍扁,長2-4厘米,徑1.5-3厘米,密生灰黃色短絨毛,后漸脫落,中種皮木質,兩側有兩條棱脊,上端無棱脊或棱脊不顯著,頂端有尖頭?;ㄆ?-7月,種子10月成熟。 【引自:中國植物志】

          2分布信息

          采集編號 國家 區縣 詳情
          ZXX202592 中國 安徽 安慶 岳西 詳細
          DAI495 中國 云南 西雙版納 勐臘 詳細
          • 數據統計

          • 瀏覽次數:423次
          • 創建者:種質資源庫
          • 最近更新:2024年1月3日
          精品国产无码新片速递