【作者】 苗中芹；

【导师】 郭玉海；

【作者基本信息】 中国农业大学 ， 作物栽培学与耕作学， 2014， 博士

【摘要】 大幅度提高肉苁蓉的接种率是生产的热点问题,但关于管花肉苁蓉怎样寄生到柽柳的根部形成幼苗,以及幼苗建成的机理,尚不清楚。明确幼苗建成的过程和条件,阐明幼苗建成的机理,提出提高接种率的新方法,具有重要理论意义和实际生产价值。本试验以管花肉苁蓉种子、柽柳根和管花肉苁蓉—柽柳复合体幼苗为材料,显微切片、酶的细胞化学定位等方法,研究了管花肉苁蓉幼苗建成,寄生动力和幼苗建成的调控方法。主要研究结果如下：1.采用光学显微镜和透射电镜方法观察结果表明,管花肉苁蓉吸器接触柽柳根表皮层后,顶端分化出侵入细胞。在侵入细胞引领下,吸器呈楔形结构依次侵入柽柳根皮层、中柱和木质部,最后,次生吸器与寄主的木质部连接。至此,完成了幼苗根端的形态建成。2.果胶酶和纤维素酶细胞化学定位结果表明,侵入细胞分泌果胶酶和纤维素酶,同时吸器生长的机械压力导致寄主皮层细胞被挤压变形和挤碎。吸器侵入寄主根的过程有吸器生长动力和果胶酶和纤维素酶的参与。3.采用光学显微镜和透射电镜方法观察结果表明,在吸器侵入寄主的木质部后,与寄主根中柱相连接的管花肉苁蓉次生吸器的薄壁组织恢复分生能力,在靠近寄主根端的轴向区域形成分生组织,分化出导管。4.采用光学显微镜和透射电镜方法观察结果表明,位于寄主根外侧的初生吸器的薄壁组织恢复分生能力,先分化出一团分生组织,分生组织先发育成一个“瘤体”,“瘤体”再形成一个或者多个分生组织,每团组织则分化出1个生长锥。生长锥分化出鳞叶原基,鳞叶原基形成鳞叶幼叶。至此,管花肉苁蓉幼苗芽端建成。5.管花肉苁蓉幼苗发育具有明显的单极生长特性和特殊的分枝特性。6.柽柳根的发生和伸长,芽管的生长速度和初生吸器的建成受环境条件影响。以0.4g/L IBA或者0.8g/LABT1浸泡插条,可缩短插穗的生根时间和提高柽柳生根的整齐度及侧根的发生量；在培养基质含水量为70-80%,温度20-25℃的环境条件下,有利于管花肉幼苗的建成。更多还原

【Abstract】 Increase inoculation rates of Cistanche tubulosa is a hot issue of production. But It is unclear that how do C. tubulosa haustorium invade host root and seedling establishment as well as what is the corresponding mechanisms? It has important theoretical and practical value of production that we can clear procedure and mechanism of seedling establishment and propose a new technology to increase the vaccination rate. We use C. tubulosa seeds and Tamarix chinensis roots for the test materials, microsection and cytochemical localization of enzyme and other methods to study seedling establishment as well as corresponding parasitic power and regulation. The main findings are as follows:1. The secondary haustorium top differentiated into invasive cells after contacting with host root epidermis was observed by using Light microscope and TEM. Under the guidance of the invasive cells, wedge-shaped structure of secondary haustorium to through root cortex、column and xylem of host root. finally, secondary haustorium connect with host xylem. So far,the root end of the seedling morphogenesis is completed.2. Invasive cells secrete pectinase and cellulase in the interface of haustorium and host root, at the same time, the host cortical cells are compressional deformation and destruction by the mechanical pressure of haustorium growth.The results show that parasitic powers of C. tubulosa haustorium invades host root include mechanical stress and effect of pectinase and cellulase.3. After haustorium invade host xylem, C. tubulosa secondary haustorium which close to the column of host root becoming meristem, this meristem develops into C. tubulosa vessel.4. After haustorium invade host xylem, C. tubulosa primary haustorium which close to the epidermis of host root becoming meristem,this meristem develops into a "nodules"and then this "nodules" differentiates one or more growing point. Each of growing point differentiates scale leaf primordia,then scale leaf primordia develops into scale leaf leaves.5. The growth of C. tubulosa has a unipolar growth and branching characteristics.6. Root formation and growing of Tamarix chinensis as well as growth rate and the completion of primary haustorium of germ tube are influenced by surrounding conditions.0.4g/L IBA or0.8g/LABT1can make rooting time shorten and promote lateral root development; environmental conditions of temperature20-25℃and substrate moisture at70-80%are apt to development of C. tubulosa seeding.更多还原