| The experiment had been carried out in Horticultural Experiment Station, Shandong Agriculture University. Chunjie (Prunus persica cv. Chunjie), Siyuetezaohong (Prunus persica cv. Siyuetezaohong), Xuri (Prunus persica cv. Xuri), Zhaoyang (Prunus persica cv. Zhaoyang) in protected culture were used as experimental materials. With different films (coating- anti-fog film and inner-added anti-fog film) and different intensity of artificial ultraviolet-B radiation, morphological and physiological reactions of the peach tree were studied. The main results were as follows:1. Coated anti-fog film and inner-added anti-fog film made no significant differentiations in temperature and related humidity in greenhouse in long-time; coated film maintained higher temperature and lower related humidity in the afternoon in diurnal changes than inner added film. Intensity of total ultraviolet radiation was higher udder the inner-added film than the coated film.Compared with results under inner-added film, peach trees growing under coated film contained lower growing rate and shorter shoots, lower contents of chlorophyll, lower LA, FW, DW and SLW of single leaf; No significant differentiations exhibited in contents of Carotenoid and chlorophyll fluorescence parameters under different films; peach trees under inner-added film manifested high net photosynthetic rate than that under coated film.2. With some additional artificial ultraviolet-B radiation in greenhouse, elongation of growing shoots could be restrained, and finished in advance with shorter shoots. With low intensity of artificial ultraviolet-B radiation (20μW·cm-2), new leaves were developed with a faster speed than the contrast, having a longger length. With high intensity of appended ultraviolet-B radiation (40μW·cm-2), the number of totally expanded leaves was fewer at the same time, and the leaf was shorter on specific node than the contrast. Additional ultraviolet-B radiation could reduced the leaf area, fresh weight, dry weight of single leaf and simple leaf weight of Xuri and increased that of Zhaoyang in protected culture. No significant effects of artificial ultraviolet-B radiation on leaf area appeared in Chunjie, and leaf weight of chunjie (FW and DW) increased firstly and decreed at last with higher and high intensity of ultraviolet-B radiation. Great differentiations were present in different cultivars and with different intensity of appended radiation.3. the additional artificial ultraviolet-B (20μW·cm-2) in one month could improve the contents of the photosynthetic pigments and flavonoids of peach trees in green house significantly; the increments varied with different cultivars and kinds of pigments, and the chlorophyll A was relatively inflexible, then the chlorophyll b, while the greatest variation took place in the carotenoid; With the prolongation of radiation or the increase of the intensity, the contents of the photosynthetic pigments would be lower than the contrast, while flavonoids content of Xuri and Chunjie took the same falling tendency, and flavonoids of Zhaoyang increased.4. Contents of MDA in leaf of peach tree in greenhouse were not affected with low intensity of additional artificial ultraviolet-B radiation (20μW·cm-2), and obviously increased with high intensity (40μW·cm-2). Contents of dissoluble sugar increased obviously, correlated to the intensity of additional ultraviolet ray in some extents, and felt down with too high intensity of artificial ultraviolet-B radiation (60μW·cm-2).5. With low intensity of additional artificial ultraviolet radiation in greenhouse, net photosynthetic rate of peach tree was improved in some extents, with no significant differentiation, while the stomatal conductance and the transpiration rate decreased. With relatively higher intensity of ultraviolet-B radiation in thermostat incubator, minimal fluorescence(Fo) was reduced, and maximal fluorescence increased, as Optimal photochemical efficiency of PSII in the dark(Fv/Fm) was reduced, and Actual photochemical efficiency of PSII in the light was inhibited also. With a long-term treating in low intensity of appended ultraviolet radiation, Optimal photochemical efficiency of PSII in the dark(Fv/Fm) and Actual photochemical efficiency of PSII in the light were higher than the contrast. With a high intensity, opposing results were present.
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