| Dioscorea nipponica Makino is one of the important sources of medicine; people have used medicinal plant for a long history. Today, although scientists have made sorts of medicine by chemical methods, plant medicine exploitation is attracting more and more attentions and it has a large potentiality for developing new medicines, because plants have a great many categories and the effective medical components in it are variable, they could not only be used for direct medicine exploitation but also be used for medicine precursor, structure modification is another way for producing new medicine. Germplasm resource for natural plant medicine is plentiful in china, more than five thousand kinds according to statistics, but a large amount of natural resource was consumed by traditional Chinese herbal medicine extraction method, many kinds of plants are facing eradication due to excessive excavating and illegitimate application, moreover, environmental deterioration is another factor.So far, more than three thousand kinds of plants are facing eradication, 60 to 70 percent of which are used for medicine. In recent ten years, natural plant requirements have become three times than before, which leads to vegetative cover destruction, Chinese herbal medicine resource exhaustion and natural resource decreasing , all of this has gave environment a large burden. Consequently, solving the problem of medicine resource exhaustion is imperative.Tissue culture is a wonderful approach for medicine plant cultivation, which has several fortes, for example, they could be constrained by region, season , weather and they be convenient for factory producing , meanwhile, cells grow more quickly in tissue culture than in normal cultivation, which accesses to the speed of generating tissue, so the methods that tissue culture used for seedling intermediate propagation and tissue culture, cell culture for direct medicine producing are developing more and more fleetly. Nowadays, tissue culture for medicine plant is applied in two aspects, firstly, large-scale seedlings propagation for plantlets cultivation; secondly, they could be used for direct medicine extraction from medium through callus and cell cultivation.Dioscorea nipponica Makino belongs to Monocotyledoneae,Liliales , Dioscoreaceae and Dioscorea L. which is cultivated in each province especially in Shan Xi, Hei Longjiang,NeiMenggu, Si Chuan, An Hui and Jiang Su.MS salt media supplemented with sucrose at 3% (w/v) gave the highest frequencies of shoot induction (86%) when BA was present at 2．0 mg/l and NAA at 1．0 mg/l. Sucrose at 7% (w/v) was the single most significant medium constituent for microtuber growth. The cytokinin, N-benzyladenine (BA) in the range of 0．5-2．0 mg/l showed strong enhancing effects on microtuber induction only when used in conjunction with the auxin alpha-naphthalene acetic acid (NAA), with the effect of NAA increasing from 0．5 to 2．0 mg/l. The heaviest microtubers were formed on media containing 1．0 mg/l BA and 2．0 mg/l (0．073 g), especially with 7% sucrose (3．46 g). Using media containing 1/2 MS, 2% sucrose and 0．1% (w/v) activated charcoal, the percentage of rooting was maximal when supplemented with 1．0 mg/l BA and 0．5 mg/l NAA for the in vitro produced shoots (95%) and BA and NAA both at 0．5 mg/l for the microtubers (100%). When removed from culture flasks and transferred into sterilized soil in a greenhouse, most of the hardened plantlets survived (over 91% after one week), and they were suitable for field planting after one month.
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