Research On Tissue Culture Technology Of Phoebe Zhennan

Phoebe zhennan is a evergreen tree belonging to the phoebe genera of Lauraceae family.It is a unique and precious tree species with a straight stem shape,hard wood and long life in China.It is also an ideal garden tree species and landscaping tree species.It has clear and beautiful wood texture,good corrosion resistance,and excellent wood species.Now people have discovered that the essential oil of Phoebe zhennan has the effect of inhibiting the growth of tumor cells.Due to the small amount of natural distribution of Phoebe zhennan,the scarcity of seed collection resources,the poor cold resistance and the long seedling period,the resources of Phoebe zhennan are decreasing day by day,and there is a serious shortage of supply and demand.It is urgent to use tissue culture to breed rapidly.At present,although there are some achievements in the cultivation and propagation techniques of Lauraceae species,there are few studies on tissue culture of Phoebe zhennan.No successful cases have been found yet.Only some scholars have induced callus of Phoebe zhennan,but no further In-depth study.In this study,the tissue culture techniques of Phoebe zhennan were studied from the establishment of aseptic system,primary culture,subculture,rooting induction and callus induction optimization.The tissue culture conditions suitable for Phoebe zhennan were screened and the construction was complete.The planting system of Phoebe zhennan has important significance for protecting the germplasm resources of rare tree species,increasing the breeding method of Phoebe zhennan,expanding the selection of tree species in garden landscapes,and solving the lack of status quo and extensive application and promotion of Phoebe zhennan resources.The main results of the research on the tissue culture system of Phoebe zhennan are as follows:(1)The best disinfection method for the bud stem segment of Phoebe zhennan was 4.5min with 0.1%Hgcl2,the pollution rate was controlled at about 40%,and the germination rate was the highest,reaching 68.42%.On this basis,when is increasing the treatment time.There was no difference in the pollution rate of 5.5 to 15min with 0.1%Hgcl2,but the germination rate dropped to 15.39%.When the explants were treated with 0.1%Hgcl2 for 3.0 to 3.5 min,or with different concentrations of Naclo for 15 min,the pollution rate increased suddenly,and the pollution rate reached about 90%.(2)At the start culture,the optimal bud induction medium is 1/2 MS+2.0 mg/L 6-BA+1.0 mg/L ZT+0.3 mg/L IBA,and the best explants were young shoots with budding stems.When the time of taking materials was controlled in April,the effect of starting culture was the best.The pollution rate was only 6.72%,the survival rate was as high as 95.96%,and the germination rate was 71.19%.(3)When inducing the proliferation of buds,the best culture condition was that the germination of the explants aged 2-3 months,and 1/2 MS was used as the base medium,When TDZ concentration was 0.5 mg/L and GA3 concentration was 4.0 mg/L,,the proliferation coefficient was up to 2.92,the proliferation occurs early,the red and green value-added buds grew well and grew vigorously.(4)Root induction of Zhennan was carried out with different concentrations of NAA and IB A at 0.01 mg/L-1.0 mg/L.When rooting induction was carried out,only callus and no roots were found.When the medium was 1/2MS+0.01 mg/L NAA+0.2 g/L activated carbon,it could successfully induce a white strong root system with a length of about 2 cm,but the rooting rate was not high,only 8.33%.(5)Callus induction of Zhennan was carried out by using young leaves as explants and MS+0.5 mg/L 6-BA+5.0 mg/L NAA as medium.After dark culture for about one week,the highest rate of callus induction was 96.87%.A large number of dense point-like callus were induced on almost explant,with soft texture and white to green color.