| Dang Gui (Angelica sinensis) is one of the characteristic medicine plants in Gansu, China. It has been reported to enrich the blood, stimulate blood circulation, regulate menstruation, and relieve pain. Because of its broad pharmacological effects, it has been using for thousands of years in conventional Chinese medicinal prescriptions. But traditional mode of breeding has many disadvantages, such as long period, low efficiency, and its quality and production field tends to be reduced constantly by various diseases. Moreover, seeds of A. sinensis must be sowed in uncultivated soil with the mode, which badly destroys natural vegetation. Therefore, the purpose of this study is to develop a raise seedling system for A. sinensis by tissue culture, which will offer the optimal technological process. And the development of plant tissue culture methods will be vital to the extended utility of A. sinensis.The experiment is carried out on the basis of axenic propagation system, then two explants are adopted respectively in this study: ①petiole, root-tip and lamina of the seedling from seeds as explants to research the effect of various concentrations of hormone and different culture condition on organic differentiation, ②apical-bud from one-year-old plant to made an attempt to new source of explant..The main results of this research are as follows: ①50mg/L antibiotic solution is the optimal disinfector of explants, and penicillin is superior to gentamycin, contamination rate of explants only is from 4% to 10%. ②Petiole, root-tip and lamina are cultured on H medium supplemented with 0.5mg/L 2,4-D to induce callus. The induction rate of callus from petiole is higher than that from root-tip and lamina. Additionally, the H medium is easier than the MS and B5 mediums to callus induction of A. sinensis. And 2,4-D plays an important role in callus development. ③It can prevent callus to brown effectively to plus 0.1%g/L Ac and transfer many times. After two weeks, these callus are sub-cultured on MS medium supplemented with 0.5mg/L 2,4-D and 1.0mg/L BA or 0.05mg/L NAA and 0.5mg/L KT for regenerate. ④MS medium supplemented with 0.02mg/LNAA and 0. 1mg/L KT are optimal for callus re-differentiation, and the differentiation rate is 98%. ⑤The regenerated shoots are rooted on half strength MS medium supplemented with 1.0mg/LIBA and 300mg/LLH and 3% white sugar. Three weeks later, the plants will develop more numbers of rooting (4 roots per explant) and the rooting rate is 100%. ⑥MS medium supplemented 5.0mg/LBA and 1.0 mg/L IAA are better for bud proliferation. After two weeks, the apical-buds are transferred to elongation medium. ⑦The rooted plantlet are transplanted to plastic cups containing a mixture of humus soil and vermiculite (1:1). After acclimatizing, the survive rate is up to 80%.During induction callus, the optimal condition is early-stage in dark and later in light under the temperature of 23 ℃. While the temperature from 20 ℃ to 22 ℃ is better to proliferate and re-differentiate of callus. Besides, it is also necessary to root early stage in dark and later in light. During tissue culture, illumination intensity is from 2000 Lx to 3000Lx; illumination time is 16 hours per day.
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