【作者】 黄燕华；

【导师】 林思祖； 赖钟雄；

【作者基本信息】 福建农林大学 ， 森林培育学， 2006， 硕士

【摘要】 杉木是我国南方最重要的造林树种之一，目前大多数的杉木林是在连载地上经营起来的。长期的林业生产实践表明，连栽导致地力衰退，生产力下降，而且这种生产力下降现象随着杉木连栽次数的增加越加明显。自毒作用是导致其连栽障碍的一个重要原因。 本研究采用不同杉木无性系，通过植物组织培养技术获得杉木供试材料，并通过组培苗进行胁迫试验，在尽可能排除其它外界干扰因子影响的条件下，从生物量、质膜透性、几个保护酶系统、内源激素及细胞超微结构等方面研究了杉木自毒物质之一(邻羟基苯甲酸)对不同杉木无性系苗生长、生理生化过程及细胞结构的影响，进一步研究了杉木自毒作用机理，并为选育杉木耐自毒物质品系及建立耐自毒物质评价指标提供科学依据和理论参考。研究结果表明： 1、植物无菌体系的建立与灭菌剂种类、浓度和灭菌时间密切相关，通过对比试验，发现依照75％酒精浸泡1min→0.20％升汞浸泡9min→无菌水冲洗4-5遍的操作次序是杉木外植体灭菌的较佳处理方法，且将接种后污染的材料进行再一次的重复灭菌，则可以降低污染率，提高存活率。 2、采用正交试验分析基本培养基、6-BA、糖对杉木继代增殖的影响。试验结果显示，三个试验影响因子的大小顺序依次是基本培养基＞糖＞6-BA，筛选出杉木增殖较佳的培养基配方是MS+IBA0.3mg／L+6-BA0.4mg／L+AC1.0g／L+糖40g／L。 3、胁迫30d后，不同浓度邻羟基苯甲酸胁迫下不同杉木无性系组培苗株高、生物量下降，且随着胁迫浓度的增大，下降趋势越明显，中毒症状也更明显；与对照(无邻羟基苯甲酸)相比，邻羟基苯甲酸胁迫下的优1、优2无性系高生长及生物量下降幅度较大，对照(普通无性系)下降幅度较少，但其高生长量、生物量始终低于前两个无性系。 4、相同胁迫浓度下，胁迫前20d优1、优2及对照(普通无性系)相对电导率总体上变化较为平缓、20d后急剧上升；而3个无性系丙二醛含量随胁迫时间的延长呈递增趋势。相同胁迫时间下，3个杉木无性苗相对电导率及丙二醛含量均随胁迫浓度的上升而增加。与对照(无邻羟基苯甲酸)相比，3个杉木无性系电导率、MDA增加幅度大小分别是对照(普通无性系)＞优2＞优1，即胁迫下对照(普通无性系)膜透性最大，膜脂过氧化程度最严重，优2无性系居中，优1无性系则表现为对邻羟基苯甲酸胁迫具有较强的抵抗能力。 5、在自毒物质邻羟基苯甲酸胁迫下，不同杉木无性系组培苗保护酶反应较敏感。3更多还原

【Abstract】 Chinese-fir was one of the most important planting trees species in southern China, but now most of them grew on continuous plantation land. The long-term forestry production practice indicated that Chinese-fir continuous plantation caused soil degeneration and productivity declining, which had become more and more evident along with the increasing times of pure plantation cultivation. The self-allelopathy is one of the most important reasons of continuous plantation obstacle.The excellent clones of Chinese-fir were used as the experimental material, which were obtained from tissue culture. The experiments were carried out by tissue culture plantlets stress, which could exclude the outside factors as much as possible. From the biomass, membrane permeability, protective enzymes, endogenesis hormone, cell ultra-structure et al, the response mechanisms of different Chinese-fir clones to the stress were studied under the different salicylic acid concentration The research would provide a theory base and an important reference for selecting and culturing the strains of Chinese-fir that could resist to self-allelopathy plant and building the evaluated indexes for the anti-self-allelopathy substance. The results were as followed.1. The build of asepsis system is closely linked with the kinds and concentration of disinfectors and the antisepsis time. By comparative experiment, the best methods on asepsis bourgeon of Chinese-fir were found. The best methods were expressed as follow: Chinese-fir explants were dipped in 75% alcohol for 1 min firstly, then in 0.20%/L HgC12 for 9 min, at last rinsed by asepsis water 4-5 times. And the polluted plants after repetitive disinfected can decline the pollution rate while increase the survival rate.2. The orthogonal experiment analysis was taken to analyze the impact of the basic cultural medium, 6-BA and sugar on the proliferation of continuous generation. The results indicated that three impact factors of the experiments were the basic cultural medium>sugar>6-BA in order, and the best medium being selected of Chinese-fir subculture was MS+IBA0.3mg/L+6-BA0.4mg/L+AC 1.0g/L+sugar40g/L.3. The seedling height and dry weight of Chinese-fir clone tissue culture plantlets went down 30 days after salicylic acid stress. The more stress conentration, the more declining更多还原