| Narcissus Tazetta L. var. chinensis Roem is one of the ten Chinese traditional flowers, which is a kind of perennial plant with beautiful color and sweet smell. And it is a favorite flower of common Chinese and a famed traditional export flower. Narcissus spread widely in China, including Zhangzhou, Fujian, Putuo, Zhejiang and Chongming, Shanghai, especially the Zhangzhou narcissus is the most fomous. But for the slowly multiplication, severe degeneration of varieties and simplex color, the production of Chinese narcissus can not satisfy the demand of global market and its development has been seriously restricted. So it's imperative to develop new varieties with modern breeding methods for the narcissus industry.In this work, experiments with different explant from Narcissus with different combinations of hormone concentration were performed to obtain higher frequency of shoot and root induction, then a highly-efficient genetic transformation system and an irradiation system were established primarily, which provided the basis of improving breeding system of narcissus variety.1. It is the key point to treat the materials by warm water about 55-60 ℃ for 2 min after sterilization by HgCl2 or alcohol, which not only can decrease the rate of contaminant plant to 5%, but also can prevent the materials from browning. Many parts of narcissus can be explants in tissue culture, such as basal plate with leaf lamina, basal plate, leaf lamina, scape. But they are different in regeneration approaches and capabilities. The basal plate pretreated at 4 ℃ for 40 days before inoculation is most effective to multiply rapidly during a short time.2. The MS medium with 10 mg/L BAP, 0.5 mg/L NAA and 30 g/L sucrose is the feasible induction medium. The medium with 5.0 mg/L BAP> 0.1 mg/L NAA and 40 g/L sucrose is found to be optimum for the development and proliferation of adventitious shoots from basal plate with leaf lamina. The medium containing 3.0 mg/L BAP, 0.2 mg/L NAA, 30 g/L sucrose and 5-10 mg/L PP333 is fit for the shoot growth, and the medium with 0.1 mg/L NAA and 15 g/L sucrose is the most efficient for rooting of bulblet. Callus is induced successfully from basal plate or leaf lamina on MS medium containing 10 mg/L BAP and 0.5 mg/L 2,4-D or 1.0 mg/L NAA respectively, but all the calluses fail to differentiate.3. Pretreating the bulbs under 4 ℃ will decrease total sugar, starch and sucrose, but increase reducing sugar, soluble proteins, and the activities of POD and CAT. Which can account for the high rate of regeneration of basal plates when pretreated at 4 ℃ lasting 40 days. During the stage of differentiation, the activities of antioxidases and the content of soluble proteins trend toward firstly increase then decrease, after 6-10 days of inoculation all come to the maximum, which is identical to the results by cytological observation. That indicates that the development of... |
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