云南方竹属一新种——乌蒙山方竹

曹安江 杨 科 虎 鑫

(云南乌蒙山国家级自然保护区管护局 云南昭通 657000)

乌蒙方竹 方竹(云南彝良) 新种(图1)

Chimonobambusa wumengensis Anjiang Cao,Ke Yang ＆ Xin Hu sp.Nov.(Fig.1)

Diagnosis:Chimonobambusa wumengensisis morphologically similar toCh.tuberculateandCh.tumidissinoda.But the significantly enlarged node differs fromCh.tuberculateand the spiny aerial roots on node differs fromCh.tumidissinoda.The shooting time,started from November and ended in April of the following year,differs from the shooting time of bothCh.tuberculateandCh.tumidissinoda.

Shrubby bamboo.Culms erect,5 m tall and 30 mm in diameter.Internodes 12－18 cm long,slightly 4-angled or terete,green,middle and lower part with verrucous base and rough,culm wall 3－4 mm thick；supra-nodal ridge raised at branching nodes,the shape of the ridge is asymmetric,slightly ridge at branchless nodes；sheath scars distinct,brown,with a dark brown tomentose ring and with the persistent remains of sheath base.Intranode ca.2－4 mm,with a ring of sparse or dense spiny aerial roots.Culm sheaths deciduous,papery or thickly papery,long triangular.The sheath is longer than internode at the middle and lower part of the culm,but shorter or equal to internodes at the upper part of the culm.The abaxial surface of the sheath covered with densy yellowish-brown hirsute,which becomes verrucose residue later.Shoot sheath reddish-purple in the sun,but greenish-white in the backlight.Sheath ligules unconspicuous；sheath blades is very small,almost absent,only 1－2 mm long,no articulation at the junction of sheath blade and culm sheath.Branches 3 per node；leaves 2 (or 4) per ultimate branch,usually 3 leaves；leaf sheaths smooth,oral setae sparse and easy falling；ligule minute,only 1 mm high；leaf blade oblong-lanceolate,(12－18) × (1.2－2.0) cm,papery or thickly papery,Lower surface glabrous,gray green,secondary veins 5－6 paired,crossed veinlet distinct.Inflorescence unknown.The shooting time started in Nov.and ended in Apr.of the following year,but the heydays are in middle Nov.and in March of the next year.From Dec.to early March,due to the lower temperature,the number of the shoots become less,the young shoots grows very slowly and lignify rapidly.The shoot is delicious.It is an excellent bamboo for shoot production,which is worthy of development and utilization.

Type:Yunnan Province,CHINA:Wumeng Mountain National Nature Reserve,Yiliang County,Zhaotong City,27°53′17″N,104°2′34″E,1 154 m alt,7 December 2021,CAO Anjiang ＆ ZHOU Xunlin,20211207012.(Holotype:NF)

灌木状竹类；秆直立,高5 m,直径约30 mm；节间长12～18 cm,微呈四菱形,绿色,中下部具有疣基而粗糙,秆壁厚3～4 mm；秆环在分枝节处隆起成脊,脊处形状不对称,下部不分枝节处微隆起；箨环明显,棕色,具棕色绒毛,留有鞘基部残余；节内长2～4 mm,环生刺状气生根。秆箨早落,纸质或厚纸质,长三角形,位于秆中部以下的秆箨长于节间,位于秆上部者短于或等长于其节间,秆箨背面红紫色或绿白色但边缘红紫色笋箨向阳处为条块状的红紫色,背面密被黄褐色向上伏生的小刺毛,脱落后在箨鞘背面留有黄褐色粗糙疣基；笋箨背光处为绿白色,背面刺毛相对较少,脱落后留有黄褐色粗糙疣基；箨舌不明显；箨片极小,几近于无,长仅1～2 mm,基部与箨鞘连接处不具关节。每节3 分枝；末级小枝具2 或4 叶,通常3 叶；叶鞘光滑,鞘口具稀疏易落的繸毛；叶舌低矮,高仅1 mm；叶片长圆状披针形,长12～18 cm,宽1.2～2.0 cm,纸质至厚纸质,下表面无毛,灰绿色,次脉5～6 对,具小横脉。花果未见。笋期11 月至翌年4 月,笋白色,笋味香。气温低时笋的生长速度很慢,笋木质化很快,可食部分较小。

云南:昭通市彝良县云南乌蒙山国家级自然保护区,27°53′17″N,104°2′34″E,海拔1 154 m,2021 年12 月7 日,模式标本号20211207012,采集人:曹安江、周训林,存南京林业大学树木标本馆。

该种形态介于永善方竹[1](Ch.tuberculataHsueh et L.Z.Gao) 和筇竹[2](Ch.Tumidissinoda(Hsueh ＆ T.P.Yi ex Ohrberger)Hsueh et T.P.Yi),该种笋箨颜色既有永善方竹的红褐色又有筇竹的绿白色；秆环隆起成脊似筇竹,节内环生刺状气生根又似永善方竹；叶片大小介于永善方竹和筇竹之间,正面颜色深绿似永善方竹,背面颜色灰绿色似筇竹；笋期自11 月初至翌年4 月初,但发笋盛期有2 次,分别在11 月中旬和翌年3 月中旬。自12 月初至翌年3 月上旬,由于气温低,发笋数量很少,即使有少量发笋,新笋生长缓慢而且木质化快。这一发笋特性,在永善方竹与筇竹的出笋期之间。该新种的竹笋味美,是优良的笋用竹,保护区在加强该竹子种质资源保护的前提下,应与地方政府加强合作,合理开发利用这一珍贵的竹子资源,真正做到保护与利用的协调,保护区建设与周边社区经济发展的协调。

该新种模式产地既有永善方竹,亦有筇竹。永善方竹分布在海拔相对较低的山体下部,筇竹分布在海拔相对较高的山体上部[3－4],该新种被发现位于这2 个竹种分布的交界处。由于方竹属与筇竹属的分类系统关系一直存在争议[5－10],该新种的发现,对进一步厘清方竹属与筇竹属的进化关系具有重要意义。