| Viburnum is a genous of excellent ornamental tree species, has not been widely applied in landscaping yet. In this rearch, 6 species of Viburnum (V. sempervirens K. Koch var. trichophorum Hand.-Mazz.,V. dilatatum Thunb.,V. luzonicum Rolfe,V. propinquum Hemsl.,V. setigerum Hance and V. melancarpum Hsu) in Zhejiang provience were served as experimental materials. Their biological and ecological characteristics, seed and seedling morphology were observed. After experiments on seed germination, cutting propagation and photosynthetic characteristics measuring, recommendations for their application in the landscape were made. The thesis also provided some valuable information on the resources development and utilization of Viburnum, and still gave a new way to break seed dormancy. The main conclusions were as follows:(1)The fresh seeds viability of the 6 species Viburnum plant reaches a higher survival rate, which is 90%. Through dissecting the seeds, this research discovers that the seed has tiny embryo with a rich endosperm and the embryo is not fully differentiated when the seeds harvested, they belong to a type of embryo morphology dormancy. The seeds coats had a good water permeability. Under natural conditions seeds need about 15 months to germinate. Exogenous hormone could not affect their germination at 20℃. But the seed dormancy could be effectively overcomed by alternative stratification (first 30℃90~120 day then 4℃over 60 day).The the order from warm to cold could not be inversed. The germination rate of V. setigerum is the highest, up to 90%, and V. sempervirens the lowest, to 68.89%. It was also observd that their seedling morphology were different. The cutting survival rate of V. luzonicum was the highest, up to 95.56% by treated with ABT1's 50mg·L-1 for 3 hours. V. dilatatum is the second, to 86.67% by the same treatment. The cutting survival rate of V. propinquum was 81.11% by treated with ABT1's 100 mg·L-1 for 3 hours. The cutting survival rate of V. sempervirens and V. setigerum were 82.22% and 60.00% respectively by treated with ABT1's 100 mg·L-1 for 6 hours. The cutting survival rate of V. melancarpum is the lowest , only to 40.00% by treated with ABT1's 200 mg·L-1 for 6 hours. The exogenous hormone had a significant effect on their rooting rate, root number and the length of roots.(2) By field survey and phenophase observation, it was found that the branch and crown shape of the 6 species of Viburnum, including evergreen and deciduous, had beautiful appearence. Their flowers were white, except for the V. propinquum light green. All flower cymes were bisexual. The fruit of the V. propinquum is blue, the V. melancarpum′s black but others red. All flowers and fruits were beautiful.The photosynthetic capacity of the 6 species of Viburnum is arrayed as follows: V. setigerum > V. luzonicum > V. melancarpum >V. sempervirens > V. propinquum> V. dilatatum. V. setigerum could adapt to a wide range of light, but V. dilatatum could not.According to their ornamental and photosynthetic characteristics, the 6 species of Viburnum can be applied to the landscape architecture through a variety of ways,such as Specialized Garden, isolated planting and planting with other plants at the edge of woodland.
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