Study On Regeneration Of Chrysanthemum Koraiense Nakai

C. koraiense Nakai belongs to Composite family and Chrysanthemum genus. C. koraiense Nakai is a wild perennial herb distributed in hillside and roadside. It is an important economic resource for eatable and medicament. In recently years, the nature resource of C.koraiense Nakai has been over-exploited as more and more. C. koraiense Nakai becomes very rare.The study on establishment of in vitro regeneration system in C. koraiense Nakai was done to solve the shortage of C. koraiense Nakai seed source for cultivation and planting. The stem segments and stem apex of C. koraiense Nakai were used as explants. The tissue culture experiments were concerned with callus induction and differentiation, shoot induction and multiplication, rooting and transplanting.The main results are shown as follows:1. The culture of callus inductionIn the process of callus induction, using aseptic stem as explants showed some advantages such as convenient to get explants, easy to operate and high survival rate. Callus of C. koraiense Nakai was inducted by aseptic stem, the results showed that MS+6-BA0.5mg·L^-1+NAA0.1mg·L^-1 medium was suitable for callus induction. The callus induction rate was up to 83.3%.2. The culture of adventitious bud inductionThe calli were cut into knob and cultivated in the medium MS adding different concentration of 6-BA, NAA and IAA. The effect of 6-BA on the result was significant. The results showed that the ideal medium was MS supplemented with concentration of 6-BA0.2mg·L^-1 and NAA 0.1mg·L^-1. The adventitious bud induction rate was over 90%.3. The culture of shoot differentiation and multiplicationThe stem apex of C.koraiense Nakai was taken as explants for shoot differentiation and multiplication. Lower concentrations of cytokinin promoted buds proliferation. Excessive concentrations of cytokinin inhibited seeding propagation. The results indicated that the cluster buds were obtained in the medium of 1/2MS+6-BA 0.5mg·L^-1+NAA 0.1mg·L^-1.The shoot multiplication coefficient was 5.77 after thirty-day induction culture, and the buds grew healthy and strong.4. The culture of rootingThe condition of variational temperature and light culture was optimum for rooting of C. koraiense Nakai. According to the rooting situation, 1/2MS+NAA0.1 mg·L^-1+IAA0.2mg·L^-1 medium was suitable for inducing roots. The rooting rate could be up to 100% and plantlets were strong. 5. The transplanting of C. koraiense NakaiBy comparing four different kinds of transplanting substrate, it was found that the most suitable transplanting substrate was sands or cinder. The survival rates were 98%, 94% respectively.