Effect of Different Organic Appendices on Protocorm Multiplication and Seedlings Rooting and Growth-promoting of Dendrobium officinale

Organic appendices play an important role in the tissue culture of Dendrobium officinale and more organic appendices with optimum effect may be found out with broader screening. Several natural organic compounds were combined and added in the medium in the course of subculture multiplication and rooting to explore new organic appendices and combinations with promotive action. Potato juice of 100 g/L and other organic appendices of 100 g/L (banana juice, maize juice, watermelon Juice, litchi juice and wheat flour) were added in the multiplying medium. Potato juice and maize juice had optimum effect on the multiplication of protocorm (mean multiplying 5.66 times and the fresh weight enhancing 4.12 times), while the differentiation degree was low (with the 3rd differentiation rate of 67.9%), as the suitable additives in the early stage of protocorm subculture. Adding potato juice and wheat flour, the protocorm differentiation rate (mean rate 95.1%) and the increase of fresh wheat (mean 5.35 times) were the highest, and the robustness of seedlings was also the highest, as the suitable additives at the later stage of protocorm subculture. During the period of rooting and growth-promoting, banana juice of 100 g/L and other organic appendices of 100 g/L (potato juice, maize juice, watermelon juice, litchi juice and wheat flour) were added. Banana juice and wheat flour had optimum effect, mean rooting rate being 96.6%, mean root length being 4.82 cm, very significantly different with others. Both maize and wheat flour were from plant seeds and were nourishing. Their promotive effects in tissue culture of D. officinale had not been reported. The results of this study had some realistic significance to improve the seedling quality and shorten the culture cycle of D. officinale.