| Anthurium (Anthurium andraeanum Lind.) is among the most popular ornamental plant of Araceae, with beautiful showy flowers, exotic foliage and long lasting inflorescences. Anthurium, using bulking up via a callus stage, followed by adventitious bud formation, has been proposed as an interesting possibility for large scale production. For many applications, the method of somatic embryogenesis has powerful advantages for plant regeneration: the high multiplication rate, enormous numbers and genetic stability.Somatic embryogenesis and plant regeneration of anthurium has been reported in a few articles recently, which only focus on the induction of somatic embryogenesis. This thesis tried to study the different factors affecting somatic embryogenesis, histological structure and ultrastructure, and physiological and biochemical changes. The results are as follows.1. Modified MS supplemented with 2.0,3.0mg·L-1 2,4-D, 0.5 mg·L-1 KT, 2% sucrose and 1% glucose was suitable medium for embryogenic callus induction from explants, and up to 90.3% of explants produced embryogenic callus and embryogenic structures after 40 days culture. 62.9% of somatic embryos developed after 20 days culture on modified MS medium containing 0.5mg·L-1 6-BA and 3% sucrose under light conditions of 20μmol·m-2·s-1 and converted into plantlets with shoots and roots after 30 days on the same medium. Etiolation of the explants could be overcomed with the preliminary culture in the medium supplemented with TDZ, and the percentage of embryogenic callus could be increased at the concentration of 0.4 mg·L-1. Somatic embryos grew slowly and were difficult to germinate in liquid culture. Solid culture is more suitable than liquid culture for the germination of somatic embryos.2. Significant differences of the somatic embryogenesis potentialities between different explants that the leaf is more suitable as the explants for somatic embryogenesis of anthurium. Significant differences of the somatic embryogenesis potentialities between the 5 cultivars tested, the induction of embryogenic callus of the cultivar 'Sonate' was easier than other cultivars.3 Anatomic structures of different stages of somatic embryos were researched. The results showed embryogenic callus derived from the surface or subsurface layers of explants. Somatic embryos were observed by scanning electron microscopy. The results showed that the structure differences between embryogenic callus and non-embryogenic callus were distinct. We found that the cells of embryogenic callus were often small and equal. There were cell masses consisting of many embryogenic cells and had the shape of ball, while the cells of non-embryogenic callus were so big that they cannot form cell masses and there were interspaces between them. The plantlet regenerations were developed from global embryos, scutellate embryos, and mature embryos. The observation of histological structure and ultrastructure proved the process of somatic embryogenesis of anthurium.4 In the process of somatic embryogenesis, close relationships have been showed between somatic embryogenesis and the activity of three antioxidant enzymes (SOD, POD and CAT), of which SOD and POD play a leading role in the induction of embryonic callus, and CAT plays a dominant role in the development and maturation of somatic embryos with the increase of its activity. The changes of the accumulation of soluble protein and saccharide have a close relationship with the induction and development of somatic embryos.
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