导　　师： 康向阳

学科专业： I0701

授予学位： 硕士

作　　者： ;

机构地区： 北京林业大学

摘　　要： 杜仲/(Eucommia ulmoides Oliv./)隶属于杜仲科,单属单种存在,雌雄异株,是一种能够代替天然橡胶的胶源植物。通过选育多倍体品种提高杜仲叶片的含胶量,对于杜仲胶产业化开发具有重要价值。 本文以杜仲为材料,在掌握小孢子母细胞减数分裂规律的基础上,就杜仲花粉染色体加倍技术以及2n花粉萌发特点进行了研究,并取得了一定进展。 /(1/)掌握了杜仲雄株花粉母细胞减数分裂进程及其与花芽外部形态变化的关系。杜仲花粉发生及发育通常位于每年的3月中下旬到4月上旬之间,而完成花粉母细胞减数分裂大约3-5d；杜仲不同植株以及同一植株不同花芽的小孢子母细胞减数分裂进程均存在一定差异；随着花粉母细胞减数分裂进行,花芽长度、花药群张开角度等杜仲雄花的外部形态相应发生一定变化；可根据杜仲花芽外部形态变化初步推断小孢子母细胞减数分裂时期,对于花粉染色体加倍有效处理时期的即时判别有一定指导价值。 /(2/)初步掌握了高温诱导杜仲花粉染色体加倍的技术条件,获得了一定比率的2n花粉。试验结果表明,将“树木高温加倍器”用于杜仲等高大树木非离体状态下雄花芽的高温加倍处理,可收到良好的效果；从高温诱导杜仲花粉染色体加倍试验所涉及的细线末期、粗线期、后期Ⅰ、末期Ⅱ等处理时期看,以粗线期施加42℃-46℃持续处理4h相对较好,连续两年的2n花粉比率分别达到24.35/%和32.63/%。2009年的最佳处理是在粗线期,处理条件为42℃持续4h,最高2n花粉百分率24.35/%。杜仲2n花粉诱导比率较低,与处理时期选择不当以及杜仲小孢子母细胞减数分裂不同步等有关。 /(3/)筛选出适宜杜仲花粉萌发率测定的离体培养基,初步证明杜仲2n花粉同样具有生活力。单因素试验结果表明,有利于杜仲花粉萌发蔗糖浓度、H3B03浓度、CaCl2浓度分别为100g·L-1、30mg·L-1和10mg-L-1；进一步通过正交试验设计筛选出杜仲花粉萌发试验的适宜培养基为蔗糖浓度150g·L-1+H3BO3浓度20mg·L-1+CaCl2浓度10mg-L-1的组合；通过花粉培养、花粉管长度测量以及免疫荧光观察,证明2n花粉相对单倍性花粉萌发迟缓且萌发数量少,但萌发能力弱于单倍性花粉,在竞争中常常处于劣势。 Eucommia ulmoides Oliv. is a single species belonging to Section Eucommia and is dioecious. It is a rubber-resource plant which can be used as a substitution for natural rubber. To improve the amount of Eucommia leaf gum by polyploidy species selection can have a great value for gutta-percha industrial development. This research used Eucommia ulmoides Oliv as the material, based on the result of its pollen mother cells meiosis /(PMCs/) development, has carried out studies on pollen chromosome doubling and 2n pollen germination characteristics of Eucommia ulmoides Oliv. Some progresses have been made. /(1/) The correlation between the meiosis stages of PMCs of Eucommia ulmoides and its male bud morphological changes was learned. Eucommia ulmoides pollen occurrence and development usually started in the late March and early April every year, and its meiosis process last approximately 3-5 d; some differences existed in the PMCs process of different plants and flower buds of the same plant of Eucommia ulmoides; as the development of the PMCs underwent, certain morphological changes of flower bud length, anther base opening angle of the flower appeared correspondently; PMCs stages of Eucommia ulmoides can be preliminary speculated through its flower buds morphological observation, which could be used as a guideline to the immediately determination of pollen chromosomes doubling treating period. /(2/) Pollen chromosome doubling technique by high temperature induction of Eucommia ulmoides was preliminary learned. And a certain percentage of 2n pollen was obtained. The results showed that, the 'Trees High Temperature Doubler Device' for the tall trees of Eucommia chromosome doubling in vitro status could achieve good results; We had treated several stages including the Late leptotene, pachytene, anaphaseⅠ, telophaseⅡ, etc, and the result showed that using temperature of 42℃-46℃and treating time of 4h to treat pachytene stage of Eucommia ulmoides could gain better result, among which when the treating temperature and time are of 42℃and of 4h respectively can obtain the highest 2n pollen ratio of 24.35/%. The relatively low rates of 2n pollen may attribute to a high asynchronism of meiosis of degree of Eucommia ulmoides and an improper treating stage. /(3/) The thesis selected the suitable vitro culture medium for measuring rates of pollen germination and had initially proved 2n pollen of Eucommia was also violable. Single factor test results showed that sucrose concentration of 100g.L-1, H3BO3concentration of 30mg.L-1 and CaCl2 concentrations of 10mg.L-1 were conducive for pollen germination of Eucommia ulmoides; further selection by orthogonal design was showed the optimal medium for Eucommia pollen germination was combination of sucrose concentration of 150g.L-1+H3BO3 concentration of 20mg.L-1+CaCl2 concentration of 10mg.L-1; by the pollen culture, pollen tube length measurements, and immunofluorescence observation, proved 2n pollen germination speed and amount were weaker than these of haplotype pollen, and its germination viability was weaker, too often was at a disadvantage in the competition.

关 键 词： 杜仲 花粉母细胞减数分裂 高温加倍 花粉 萌发特点

分 类 号： [TQ9 TN3]

领　　域： [化学工程] [电子电信]