| Magnolia wufengensis var is a new Magnoliaceae species with the beautiful tree shapes, variable flower types and colors, which has not only the high scientific and academic value but also a reasonable prospect on the ornanment and greening. Unfortunately, as result of its narrow geographic distribution, scarcity of its individuals, inadequate protective measures, there is a dangerousness of its population extinction. The plant tissue culture of the M. wufengensis was carried out in this study. firstly and the objective of this research is to provide the basis for its seed breeding and germplasm conservation The main conclusions were as follows:(1)The optimal explants:the buds, the seeds, the leaves and the stem segments with a bud of M. wufengensis were cultured as the four kinds of explants.The results show that the best explant is the stem segments with a bud, the best time to obtain the explants is in September, during this period, the rate of browning is lower, the survival rate is higher.(2)Establishment of the sterilization and the optimal basic medium:the optimal sterilization method for the stems segments with buds was like this:soaked in the 75% ethanol for 30s then washed with the sterile water for 3-4 times, and then soaked in the 10% NaClO for 10mins and then washed with sterile water as least 4 times. It is less harm and more thorough sterilizated for the explants to be treated in this way, the survival rate is higher than 85%. The optimal initiation basic medium for the M.wufengensis is MS medium, sucrose is more suitable to be carbon source than the fructose and plain edible sugar, which optimal concentration is 30g·L-(3)Inhibition of browning:the rate of the browning can be reduced to some extent by pretreatment of the explants material, adding reagents in the medium and changing environmental conditions, we can have a good effect on inhibition of browning by treating the explants in PVP solution, frozen the branch materials for 4 hours, adding 5mg/L of ascorbic acid or 2g/L of activated carbon into the medium. In addition, the temperature and the light are also the important factors for browning, a better measure of browning inhibition is culturing the materials in the shade under 15℃-25℃for 15 days at first and then move into the full light.(4) Take the stems segments with buds as the explants, the optimal initial medium for M.wufengensis was MS+6-BA2.0mg·L-1+NAA1.5mg-L-1+VC5mg·L-1+AC3mg·L-1, the survival rate can arrived at 88.3%, the browning rate can be reduce by 25.1% through adding the 5mg·L-1 Vc and 3mg·L-1 AC into the culture medium. MS+6-BA1.0mg·L-1+NAA0.2-0.5mg·L-1 is the optimal proliferated medium, the multiplication coefficient is 4.4. MS+6-BA12mg·L-1+KT5mg·L-1+NAA2.5 mg·L-1 is the optimal medium for the stem segments with bud to induce the callus, and the induction rate is about 45.4%. The combination of 6-BA and KT has the significantly effects on callus inducing than using them respectively.
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