Optimization Of Tissue Culture System And Proliferation Of Rhizome In Bioreactor Culture Of Cymbidium Sinense Willd.

Cymbidium Sinense Willd. (C. sinense Willd.) is one of the advanced floweres which have great ornamental value. However, large scale production is impossible due to low propagation rate. Tissue culture is the important way for solving the problem of low propagation. In this study, in order to establish the system of tissue culture and rapid propagation for C.sinense Willd., rhizomes. were used as explants to investigate the factors affecting proliferation of rhizome, proliferation of shoots and rooting in vitro; In addition, the effects of several physical and chemical parameters on rhizome proliferation and growth during air-lift bioreactor culture were examined, which provide the theoretical basis reference for large scale production of C.sinense Willd. The several factors affecting proliferation of rhizome were investigated, The results showed that it was not suitable when H1 and H2 were individually used as culture medium for rhizome differentiation and growth, but combination of both media was better than MS medium. The medium supplemented with BA and NAA promoted rhizome proliferation, the maximum amount rhizome with favorable growth was found in the medium of H12+BA 2 mg·L-1+NAA 0.2 mg·L-1. Sucrose was more suitable for rhizome culture than fructose and glucose, and sucrose can be replaced by white sugar. In order to induce shoots from rhizome and rooting, the several factors were examined, the results indicated that shoot formations were optimum in the medium of H12+0.2 mg.L-1 NAA supplemented with 4.0 mg.L-1 BA+NAA 0.2 mg·L-1, the medium of H12+1.0 mg.L-1 NAA was suitable for rooting.An air-lift bioreactor was used for large scale propagation of rhizome in C.sinense Willd., rhizome proliferation was better in bioreactor culture than both in culture of suspension and solid. The immersion culture was more efficient than Raft culture for rhizome proliferation in bioreactor. In addition,10 g,15 g, and 20 g rhizome inoculated in 3 L bioreactor to investigate rhizome proliferation, optimal inoculation density was 15 g, in which rhizome fresh weight and proliferation coefficient were 145.5 g and 8.7, respectively; rhizome fresh weight and proliferation coefficient were better than others when Activated Carbon at 0.3 g·L-1 concentration, respectively 151.2 g and 9.08; air volume of 0.10 vvm was good for proliferation of rhizome,while high air volume and low air volume were restrain grow. In addition,1600 Lux light intensity was considered to be the most effective light intensity for the proliferation of rhizome; During the 3L bioreactor culture of rhizome, pH and EC in the medium decreased as the culture period increased, the lowest values of pH and EC were respectively appeared at 40 days and 45 days after culture, after that both values of pH and EC increased. Total sugar concentration in the medium was exhausted after 45 days of culture, maximum proliferation coefficient was found at 45 days of culture, consequently,45 days of culture was the optimum for rhizome proliferation using bioreactor.