Study On Response Mechanism Of Tissue Culture Plantlets Of Chinese-fir Clones Under Salicylic Acid Stress

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...