| Lycium barbarum L. is a perennial deciduous bush in the solanaceous family, and is an important tree for commerical fruit growing in Ningxia areas. With the further development for medical use and health care recently, the cultivated areas have increased continuously. The convential breeding cannot meet the requirements for Lycium barbarum L improvement of varieties. The techniques, developed in 1970, for tissue culture provide the selection of resistant varieties with an advanced method. The range and frequency of somaclonal variation will be extended widely by combing these techniques with treatment of rational factors. The application of tissue culture become a highlight increasingly because of its easy operation an control, lower costs and short period of breeding. According this, the micropropagation procedure of Lyciun barbarum L.had been researched, including the establishment of selecting explant, indiniation breeding, subculture breeding, stronger nurslings breeding, rooting breeding, transplation and simplifying composition of culture medium which are benefical to the production of factory seedlings. In this study, the stems with buds of "No.2"of Lycium barbarum L.plantlet and mature tree were used for to establish the technich system of tissue culture. Multydesign and multyanalysis was used to find out the best explant proceeding of cultuning and the best composition of medium. The results were as follows: 1. Selecting explant: bottom axillarry bud as explant is effect to childhood. Butterminal buds are effect to mature age. It is the best time which April ending or May beinning that explants are collected. 2. Iniastion culture: MS medium with 6-BA1.0mg/L, IBA0.2mg/L,AC0.5g/L,is the best iniation medium to sprout to childhood. 3.Subculture culture: the MS medium with the 6-AB1.0mg/L and IBA1.0mg/Lwas applied as the subculturing medium. After 30 days culture,the multiplication rate of shoot clumps could reach 6.03. 4.Using 1/2MS with 6-BA0.5mg/L and KT0.5mg/L, stronger nurslings could be got. 5. Rooting culture: 1/2MS medium with NAA 0.1mg/L, IBA0.1mg/L is the best one in rooting culture. The rooting rate is 87%. 6.Transplantion: the transplanting medium in rotten quality soil, vermiculite and river sand by 1 to 1 to 1, is useful. 7.By simplifying composition of culture medium, removing the organic compound, the cost of test-tube seedling can be reduced;Using the natural daylight instead of the fluorescent lamp, conjoning darknees, the culturing can decrease equipment which are benefical to the production of factory seedlings. 8.The induction of somatic embryos were best when the embryonic callus were cultured on MS medium supplemented with 1.0mg/L 6-BA and 0.5mg/L IBA; the embryogenic callus (EC) frequency on the 2,4-D1.0~1.5mg/L medium was 51.0% and 56.7%. Dark and low temperature treatment (10℃) for 5 days can not only promote the taking place of the somatic embryogenesis, but also can improve its frequency (60.0%). 9.The experimental results showed that leaf situation could greatly affect "No.2"of Lycium barbarum regeneration frequency. The best explants were those 35 days apical leaves from the cultural plantlets. The high frequency of shoot regeneration was observed when leaf explants were cultured on 1/2MS medium supplemented with 1.0mg/L 6-BA and 1.0mg/L IBA. Firstly, the leaves were cultured in dark. After 8 days, the explants were transferred under light and began to directly regenerate adventitious buds in about 28 days. The maximum number of the adventitious buds was observed within 35 to 45 days. The shoot differentiation frequency was more than 90.0%. When the shoots grow to 1~2cm high, they were cut from leaves, then transferred on 1/2MS+NAA0.6mg/L+IBA0.2mg/L, and developed into whole plants. This regeneration system could apply to Lycium barbarum transgenic manipulation.
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