| The fruits of S. chinensis have long been used as traditional Chinese medicine. Recently, its demands increased dramatically for employing in pharmaceutical, food and drink industries. As a result, over exploitation has led to a rapid decline of S. chinensis in nature. The new breed of S. chinensis also didn't have proper organized cultivation. Somatic embryogenesis is considered by many as a cost-efficient method for producing uniform plants. In this paper, we study for somatic embryogenesis in S. chinensis.Somatic embryogenesis were induced from cotyledonary leaf and hypocotyl explant-derived of S. chinensis. When culture temperature was 30℃, the induction rate of friable embryogenic callus was best from hypocotyls explants on MS semi-solid medium supplymented with 4.0 mg·L-1 of 2,4-dichlorophenoxyacetic acid. The more number of somatic embryo was obtained when embryogenic callus transferred to MS medium containing 0.5 mg·L-1 BA or 1/3 MS medium with 2% sucrose, the most number of somatic embryo was 349 per 3 mg. Both the number of germinated somatic embryos and regenerated plantlets were best when somatic embryos developed in 1/3 MS medium with 2 % sucrose, which were 63 and 19. Approximately 95% of the plantlets were successfully transplanted to soil and grew into fertile plants.Resting bud of S. chinensis Baill cultured on medium supplemented with 4 mg·L-1 2,4-D produced somatic embryos directly from the surface of explants without intervening callus formation. When culture temperature was 30℃, the most number of somatic embryos was obtained in 1 mg·L-1 concentration of gibberellic acid which cultured 10 days. It also had the most germination and regeneration in this treatment. There was significant difference in the number of somatic embryo with low temperature treatment which was 4℃, but there were no effect in germination and regeneration. Cotyledonary somatic embryos were observed by histological method. The results indicate most abnormal cotyledonary somatic embryos laking apical meristem differentiation, it maybe the reason why abnormal somatic embryos couldn't develop into plantlets. Random amplified polymorphic DNA analyses found no evidence of genetic variation in the embryogenic lines. The embryogenic system used in this study appeared to be suitable for true-to-type clonal propagation of mature tissue of Schisandra chinensis Baill. It was avail for second somatic embryogenesis in 2,4-D when cultured at 30℃.An efficient somatic embryogenesis and plant regeneration protocol was developed for S. chinensis Baill using embryogenic cell suspensions and optimized media conditions. Fast growing and well dispersed embryogenic cell suspensions were developed within two months when embryogenic calli were transferred to MS Iiquid medium containing 1.0 mg·L-1 2,4-D. 1/3 MS medium was the best for both overall growth and development of somatic embryos in liquid culture. Over 3 400 viable somatic embryos were produced from one 150 mL flask with an initial cell density of 30 mg in 30 mL medium. Germinated somatic embryos developed in liquid medium converted into plantlets at a low frequency(11.2%) after transferred to halfstrength MS semi-solid medium.
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