辽东桤木的结构植物学特性

采用光镜和电镜技术系统地研究了辽东桤木根、茎、叶结构,探讨了作为北方优良造林树种的辽东桤木速生、抗寒、耐旱的结构植物学特性。结果表明:辽东桤木当年形成的实生苗根部、茎顶端部次生生长旺盛,次生结构完整,明显表现出抗寒性特征;叶片主脉明显,机械组织发达,角质膜较厚,叶肉栅栏组织和海绵组织分化明显,表现出光合能力强,耐旱性强的特性;辽东桤木根、茎次生木质部均为散孔材,根部具有发达的枝丛状类型根瘤,这些特性为其速生生长奠定了基础。

Structural Botany Characteristics of Alnus sibirica

Structures of roots, stems and leaves of Alnus sibirica were systematically studied with methods of light microscope and electron microscope in order to find its structural botany characteristics as a fine tree species of afforestation in North China, such as rapid-growth, cold resistance, drought resistance, and so on. Result showed that roots and stem apexes of Alnus sibirica seedlings formed in the first year grow rapidly and their secondary structures are complete, which manifest its cold resistant characteristics. Its obvious main vein of leaves, developed mechanical tissues, thicker cutin membranes, and obviously differentiated palisade tissues and spongy tissues indicate great photosynthetic and drought resistant abilities of Alnus sibirica. Secondary xylems of roots and stems of Alnus sibirica are all diffuseporous wood and developed phaceloid root nodules were found in root, which lay the foundation for its rapid growth.