Study On The Somatic Embryogenesis And Development Of Saposhnikovia Divaricata

The way of somatic embryogenesis is the best expression of cell totipotency. Study on the somatic embryogenesis and development of Saposhnikovia divaricata is significant for the best understanding of mechanism of the differentiation, development, occurrence of morphology, zygote embryogenesis, the theory of gene modulation and expression as well.Sapcshnikovia divaricata (Turcz.) Schischk. belongs to Umbelliferae, perennial herbaceous, it is one of most critical natural medicines in China. Its root can be used to relieve pain and cold, and has the ability of antibacterial, anti-allergy as well as tranquilizer. Current research on the somatic embryogenesis of Saposhnikovia divaricata has been focused on the ultrastructure and the stability of chromosome. Both the problem of occurrence and control of abnormal embryo in tissue culture, mechanism of the biochemical and molecular haven't been studied and reported.The aim of this paper is to study the occurrence and growth of abnormal somatic embryos, and to observe and discuss the rare phenomena of blooming and bearing fruit in the abnormal somatic embryo of perennial herbaceous. The activities of superoxide dismutase (SOD), peroxidase (POD), polyoses have been studied in this thesis, and the distribution of ergastic substance such as starch, protein and oil have also been explored here. These studies just aim at keeping the germplasm resources of Saposhnikovia divaricata and providing the academic data for the field of somatic embryogenesis.The regeneration of tissue culture is optimized in order to control the occurrence of abnormal somatic embryos at first. The study shows that it is necessary to adjust the complex procedure of tissue culture and to seek the best combination of mediums. Auxin is key factor for initiating embryogenic cell, and cytokinin is cooperating. ABA can control abnormal somatic embryos efficiently. 4%-5% sucrose can be used to heighten osmotic pressure and decrease the rate of vitrification embryo and precociousness. In addition, lower the density of inoculation and divide the callus into granules according natural form, or utilize suspension culture for 24h all can decrease the rate of abnormal embryos.Though long-term subculture will cause chromosome variation, diploid plant is the...