Regeneration System Of Aguilaria Sinensis(Lihour.) Gilg By Tissue Culture Techniques

Aquilaria sinensis （Lour.） Gilg, an evergreen broad leave tree of Thymelaeaceae family,is a China’s valuable and rare medical species with high economic, ecological and landscapingvalues. Because of overlogging, wild trees of Aquilaria sinensis tended to be endangered. Ithad been listed as the state-protected the third class rare and endangered plants, meanwhile itwas the second class protective wild plant of the state. It was of great significance to study andestablish a perfect tissue culture rapid propagation system for accelerating the protection andpropagation of Aquilaria sinensis species. Many experiments were carried out about thepropagation in vitro on Aquilaria sinensis in a tissue culture’s laboratory of the ResearchInstitute of Tropical Forestry （RITF）, China, including surface disinfection of explants,inducing callus and subculture, inducing adventitious buds and proliferation culture, andinducing adventitious roots. A suitable way of disinfecting explants was found. The suitableconcentration of6-BA, NAA, IAA and IBA to induce callus, and the optimal rate of6-BA andNAA to induce adventitious buds and subculture were all determined. The potential factors,problems and solutions in the process of regenerations in vitro system of Aquilaria sinensiswere disscussed in order to establish and perfect the theoretical basis of asexual propagationsystem of Aquilaria sinensis and to serve for the great demand of the seedlings in the forestry.The main results were as follows:1) For taking Aquilaria sinensis’s stem as explants, the disinfected effectiveness wassignificant differences between treatments by using two disinfectants, NaClO （5%,10%and20%） and HgCl₂（0.05%,0.1%and0.2%）. When NaClO was10%and HgCl₂was0.1%, thesurvival rate of explants reached maximum. It was respectively21.67%and31.67%, and it wassignificantly higher than the others. To effectively disinfect Aquilaria sinensis’s explants ofleaf, adventitious bud and stem, different disinfected way should be used. By0.1%HgCl₂andfive-minute disinfection treatment, the highest survival rate was reached for the leaf, bud andstem explants. After0.1%HgCl₂five-minute disinfection, stem’s survival rate （28.89%） wassignificantly higher than that of the leaf’s （10.56%）, and leaf’s was also significantly higherthan that of the adventitious bud’s （8.89%）. Stem was the easiest disinfected explants amongthree explants of Aquilaria sinensis 2) Cotyledon explants had the highest capability of inducing development of callus amongthe explants of leaf, adventitious bud, stem and cotyledon. Its induction rate was96.67%.Callus of cotyledon grew very fast and was viridity in color, with no browning. Followed bywas stem with the induction rate of83.33%. Callus of stem was viridity and grew fast, with nobrowning. The third was leaf with the induction rate of56.67%. Callus of leaf was dark greenand grew slowly, with seriously browning. Callus induction rate of adventitious bud was46.67%, the lowest among the test explants.3) The callus induction under different concentration of6-BA, NAA, IAA and IBA,indicated that the optimal concentration of6-BA was1.0mg/L, and the optimal concentrationrange was from0.5mg/L to2.0mg/L. The optimal concentration of NAA, IAA and IBArespectively were0.1mg/L,0.5mg/L and0.5mg/L, and the optimal concentration rangerespectively were from0.05mg/L to0.2mg/L, from0.2mg/L to0.5mg/L, and from0.2mg/L to0.5mg/L. In addition, the ratio of6-BA and NAA affected callus induction. The prescription of0.5mg/L6-BA and0.1mg/L NAA, as well as the ratio of6-BA and NAA five, the inductionrate of callus reached the maximum,93.33%. When6-BA was1.0mg/L, NAA was0.1mg/Land the ratio of6-BA and NAA was ten, callus induction proliferation of subculture reachedmaximum, and was as10times as before.4) Different concentration of6-BA and NAA, and different ratio of6-BA and NAAsignificantly affected adventitious buds induction. When6-BA was0.75mg/L, NAA was0.25mg/L and the ratio of6-BA and NAA was three, the callus induction rate reachedmaximum,96.67%. It was significantly higher than the others.5) The results of adventitious buds proliferation experiment indicated that adventitiousbuds proliferation rate was affected by both the content of6-BA and NAA, and the ratio of6-BA and NAA. When6-BA was0.75mg/L, NAA was0.15mg/L and the ratio of6-BA andNAA was five, adventitious buds proliferation reached maximum, and was as9.37times asbefore.