Study On Seed Dormancy Mechanism And Seedling Cultivation Of Oplopanax Elatus

Oplopanaxs elatus was selected as the research material, and seed dormancy mechanism and seedling cultivation of it were researched in this paper. The sexual propagation system was preliminary established, and it provided a feasible approach for protecting and developing the resources of Oplopanaxs elatus.The permeability of water and air of Oplopanax elatus seed coat is better, and it has no effect on seed dormancy. The embryos were under differentiating and deep dormancy when the seeds matured, and it was at the cardioid stage. This was the main reason for seed dormancy. The seeds must be stratified at warm temperature to finish differentiation and development of the embryos, and the developments of embryos in different seeds were not synchronous. The seed coat and endosperm have some growth inhibitors, and the inhibitory effect of water extracts from endosperm was higher than that from seed coat When the embryos finished differentiation, they could not germinate because of the growth inhibitors in endosperm.Single stratification in warm temperature (20C) or in low temperature (5C) had no effect on Oplopanaxs elatus seed to break dormancy, and stratification in changing temperature with the beginning temperature for 15C could not break seed dormancy. Stratification in warm temperature (15-20C) and then in low temperature (5C) could break dormancy. After stratification in changing temperature for seven months only a few seeds germinated, and mostly germinated after stratification in changing temperature for another one year. Stratification in changing temperature for seventeen months is the best approach for releasing from seed dormancy.Cultivation in greenhouse, the seedlings of Oplopanaxs elatus should be given humid soil, high humidity air and fitting light Shading net was used to regulate light, and the fitting transparency of it was 30 percent. After defoliation, one-year seedlings could live through the winter in greenhouse or burring outdoor with snow. One-year seedlings had no obvious stem growth. In the second year, the stem growth of some seedlings (about 5%) was earlier, and the production of it was higher. The stem growth of other seedlings (about 95%) was later, and the production of it was lower.Current-year seedlings of Oplopanax elatus could survive completely and grow normally on site in their natural distributing area. Two arid three years old seedlings could survive completely on site with environment conditions similar to their natural distributing area, and three years old seedlings could growth normally on this site. So we can magnify the natural populations and extend the distribution area of Oplopanaxs elatus through sexual propagation approach.