In Vitro Rapid Propagation And Its Cell Histological Observations Of Siraifia Grosvenorii (swingle) C.jeffery

Siraitia grosvenorii (Swingle) C.Jeffery was a kind of specific medical fruit plant attributed to the south China. In this experiment Siraitia grosvenorii (Swingle) C. Jeffery was used as the materials for the study of in vitro rapid propagation, and the observations of the cell histology on the organogenesis of the starting growth of the stem apex, stem segment, leafs slice and the hypocotyl etc. explants, the proliferation and rooting of the in vitro plantlets. The main results were as follows:1. The culture of stem apex in Siraifia grosvenorii. Using the stem apexes from the cultivars of Qingpiguo, Dongguahan and Zhenguo-one as the explants, the methods of in vitro culture on differerent cultivars were studied. The results showed that the suitable solid medium for the culture of stem apex was MS with lmg·L-16-BA and 0.5 mg·L-1IAA; the induction effect of Qingpiguo and Dongguahan was better than that of Zhenguo; during the establishment of the asepsis individual plantlet, the survival rate changed by linearity decrement, with the delay of inoculation time, and the earlier inoculation the higher survival rate was.2. The culture of virus-free plantlets from stem apex and the cell histological observations in Siraifia grosvenorii. Using the stem apex of Siraifia grosvenorii as the explants in this experiment, the effects of Ad on the induction of buds, the effects of BA on the bud induction of stem apex, and the effects of different sucrose concentrations on the bud induction were studied; meanwhile, the obtaining of virus-free plants by meiristem culture combined with heat treatment and the cell histological observation on the process of in vitro culture of stem apex were carried out. The results showed that the suitable solid medium for the free virus culture of stem apex in Siraifia grosvenorii was MS supplemented with 1 mg·L-16-BA,1 mg·L-1IAA,adding 3% sugarose; there were 3 mian paths for obtaining virus-free plantlets from stem-apex, i.e., the growth of the terminal bud, the germination of the axillary bud and adventitious buds, and the growth of the terminal bud was the main regenerative way for plantlets.3. The culture of stem segment in Siraifia grosvenorii. Using the nodes of the tender shoots of Qingpiguo as the explants, the effects of the developmental degree of the nodes on the bud formation were compared. The results showed that the rates of bud formation and contamination rose up as the levels of tissue differentiation of the tender shoots increased beween 3 and 14 nodes; and the callizing degress was at the highest level beween 7 and 10 nodes.4. The hypocotyls culture and its cell histology observations of Siraifia grosvenorii. The ideal regeneration system of Siraifia grosvenorii (Swingle) C.Jeffery by cotyledon explants was established. In this experiment, the effects of different culture media on the formation of adventitious buds from the hypocotyl, and the anatomy of the formation of adventitious buds and somatic embryogenesis were carried out. The results showed that, the highest frequency of 7.6 adventitious stoots per hypocotyls was obtained on the modified MS medium supplemented with 4 mgL-1 6-BA and 1mgL-1IAA. The anatomical observation showed that the formation of the adventitious buds and somatic embryogenesis occurred from surface layer cells of the calli derived from the hypocotyls.5. The leaf culture and its cell histology observations of Siraifia grosvenorii. The ideal regeneration system of Siraifia grosvenorii (Swingle) C.Jeffery by leaf explants was established. In this stuty, the effects of the different basic media, inoculation ways and plant growth regulators on shoot regeneration from the leaves, and observation of anatomy of the formation of adventitious buds were carried out. The results showed that the highest frequency of 5.6 buds/calluswas obtained on the revised MS medium supplemented with lmg/L 6-BA, 0.5mg/LNAA and 0.5mg/L 2,4-D. The rate of bud formation was up to 90.3% by the inoculation way which leaves faced to the surface of the medium. Addition of AgNO3 could stimulate the formation of adventitious buds, and the rate was as high as 86.7%. The adventitious buds originated from the surface layer of the compact callus.6. The proliferation of in vitro plantlets and the cell histology observations. Using the in vitro plantlets as materials, the effects of placing ways on bud induction from the explants, the effects of BA on the proliferation of buds, and further anatomical observation of proliferation from the nodes of stems were carried out in Siraifia grosvenorii.The results showed that the bud diferentiation rate of culturing way for stanza was high than that for stanza stem; the suitable solid medium for the stem segment culture was MS medium with 0.6mg·L-16-BA,0.2 mg·L-1IBA,0.2 mg·L-1IAA and 3% sucrose. The formation of axillary buds was the main path of the proliferation of in vitro plantlets. The adventitious buds did not form normally from the callus.7. The rooting culture of in vitro plantlets and the cell histology observations. Using the in vitro plantlets as materials, the effects of rooting ways on rooting and further anatomical observation of rooting were carried out in Siraifia grosvenorii. The results indicated that the adventitious roots of the base of the stem originated from the cross region of phloem and fascicular cambium; and the adventitious roots of the burl originated from the cross region of pith rays and interfascicular cambium, which belonged to inner origin. The adventitious roots of the burl formed closed to leaf gap and also beared on leaf trace. The root primordia formed early. Rooting in the burl was earlier than in the parel, so did the number of rooting. The distribution of root system was well in structure.