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作 者 ：吴先军 李平 赵振鐻 王乾 李朝銮 黄荣 陈发林

期 刊 ：植物学通报 1995年 12卷 专辑期 页码：38-40

关键词：攀枝花苏铁；营养器官；形态解剖；

摘 要 ：攀枝花苏铁具二种类型的根: 1. 向地下生长的直根系，有次生生长，维管射线由异型薄壁细胞组成。2．向地面生长的珊瑚根中具藻带层，共生藻类属念珠藻属(Nostoc)，项圈藻属(Anabaena)。小叶片边缘木反卷，叶肉分化，具单脉，木质部发育为中始式，气孔为单环型。叶脉、叶柄、上胚轴的维管束均为外韧型。组成后生木质部的管状分子，除环纹、螺纹管胞外，还有较多的长度缩短、直径增大，末端壁倾斜至垂直的单列、双列的具缘孔纹管胞。

Abstract:Cycas panzhihuaensis consists of two types of roots : 1. straight roots growing downwards with secondary growth,rays of its vascular bundle consisting of paratypic parenchyma cells; 2. horizontally grown coralloid roots with cells of algal layer in habited by Nostoc or Anabaena with the function of nitrogen fixation. The margins of pinna are not revolute. The pinna mesophyll is well differentiated with a single vein. The development of xylem is of mesarch. Stomata are monocyclic type. The vascular bundles of vein, petiole and hypocotyls have external phloem . Tuber-form elements of metaxylem have many shorted,enlarged and oblique to vertical end walled tracheids with a single or double rows of pits beside the annular and spiral ones.

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