Abstract:

To improve the efficiency and quality level of medicinal Dendrobium tissue culture, this study used D. officinale and D. nobile as test materials to investigate the effects of eight different LED light quality combinations, including red, blue, green, and white light (R6B3G0, R6B3G1, R6B3G3, R3B6G0, R3B6G1, R3B6G3, R3B3G3, W), on the proliferation, rooting, and active component contents of the kinds of Dendrobium. The results showed that both D. officinale and D. nobile had the best proliferation effects under the light quality culture of R3B6G3, with proliferation coefficients of 6.67 and 1.59, respectively, which were significantly increased by 72.8% and 101.3% compared to the control (W), with D. nobile showing the highest fresh weight under this treatment. Under the treatment of R6B3G3, the best rooting effects were observed for both D. officinale and D. nobile, with individual root numbers of 10.56 and 9.42 per plant, respectively, which were increased by 59.5% and 75.4% compared to W. At the same time, it showed the highest fresh and dry weight contents of D. officinale under this treatment, with 1.254 and 0.135 g/plant, respectively, significantly increasing by 81.7% and 1.08 times compared to W. The dry matter content was highest under the R3B6G1 treatment, significantly increasing by 29.0% compared to W, and the polysaccharide content reached its maximum value of 24.61% under this treatment, while the total flavonoid content was highest under W, at 1.46%. Under the treatment of R6B3G0 and R3B3G3, the content of total phenolics was highest of D. officinale, both increasing by 1.39 times compared to W, and the dendrobine contents of D. nobile was optimal, both at 0.5%. In short, it was beneficial for the proliferation of D. officinale adding stronger green light under the treatment of R3B6, while it was beneficial for the proliferation of D. nobile adding stronger green light under R3B6 or weaker green light under R6B3. In addition, it was effective for rooting of two Dendrobium varieties adding weaker green light under the treatment of R6B3. Furthermore, it was conducive to the accumulation of dry matter and polysaccharide in D. officinale adding weaker green light under the treatment of R3B6, while it was beneficial for the accumulation of dry matter and dendrobine in D. nobile with stronger green light under the treatment of R6B3.

Key words: LED light quality, Dendrobium officinale, Dendrobium nobile, tissue culture, proliferation effect, rooting effect, dry matter content, active substancecontent