| Broad-leaved evergreens have excellent ecological and landscaping effect, which are main materials of urban landscape in South Parts of China. But it is lacking of those, and also is humdrum in North Parts. Along with improvement of environmental requirements, and trends of warming up of global climate, it makes introduction of broad-leaved evergreens feasible. And it has been one of important tasks to landscapers in North Parts. The work could enrich biodiversity, improve environment, and develop plant introduction science. So introduction of broad-leaved evergreens are meaningful.According to basic principles, methods, and programmes, investigation and analysis of broad-leaved evergreens in Beijing present, and consulting references etc., study the introduction of cold hardy camellias in Beijing Plain is established in the dissertation. And the main achievements of the dissertation are as follow:1. Through 2 years' (2005～07) study, 'April Rose' camellia from 17 cultivars and 4 individuals from more than 500 hybrids are selected after 2006～07 winter in the microclimate. The survivals could withstand -16℃ in the winter and -9℃ in late spring cold.2. Introduced cold hardy camellias have been judged the adaptability outdoors after the nearest winter by observation, leaf tissue structure, and physiological and biochemical indices (incl. chlorophyll fluorescence parameters, relative electronic conductivity, and contents of soluble sugars and proteins, and MDA). It is noticed that the ratio of palisade to spongy tissues, CTR, SR, thichness of cuticle, F'_v'/F'_m, relative electronic conductivity, and contents of total soluble sugars could respond to cold hardy.Also, it is considered temperarture and moisture are restrictive factors of plant introduction in Beijing. And a series of cultivation and maintenance suitable to Beijing are established.Finally, the study provides data to introduction of cold hardy camellias in Beijing Plain, and relative problems and further studies are mentioned.
|
PDF Full Text Request