Studies On The Main Limitation Factors Of Introduced Broad-leaved Evergreen Plants In Beijing

During the broad-leaved evergreen plantsbroad-leaved evergreen plants introduction, the viewpoint that low temperture in winter is the pivotal limititon factor was pugned. In order to find out the main limitation factors of introduced broad-leaved evergreens in Beijing, the introdution species, the grow environment and the winter injury was investigated, and relative physiological and biochemical indexes of six broad-leaved evergreens in winter were analysed.The seasonal changes of membrane permeability, enzymatic protection system(SOD, ASA-POD, CAT, POD) and osmatica were correlated with the temperature of beijing and the cold hardiness of the broad-leaved evergreens themselves.Water was not the main factor which induced the leaves browning. Light intensity were correlated with the winter injury of broad-leaved evergreens. High light intensity could aggravate the winter injury. The injury degree directed by the ecological habits of plants. The injury on shade endurance plants were more serious than the light demanding plants.The major limitation factor of broad-leaved evergreens overwintering were not consistent with each other. It was correlated with the ecological habits. Photooxidation was correlated with the winter injury. But the injury degree was correlated with the ecological habits. For photooxidation injury, shade endurance plants were more sensitive than light demanding plants. To such plants, High light intensity was the main limitation factor. Water was not the main factor which induced the leaves browning. Moderate shade can protect shade endurance plants from photooxidation injury. For the poor ability of endurce water stress or introduced not long, water stress may be the most important limitation factor.The coclusion will have important guidance to the application and the establishment of overwintering protection of broad-leaved evergreen plants.