Effects of Enhanced Ultraviolet B Radiation on Physiological Indices and Camptothecin Content in Camptotheca acuminata Decne 紫外线-B辐射与3种植物幼苗的光合作用——光合作用对紫外线-B敏感性的比较 Cumulative effect of solar ultraviolet B radiation on pollen germination and tube growth of19 species in vitro EFFECTS OF UV-B RADIATION ON PROTEIN AND NUCLEIC ACID SYNTHESIS IN THREE SPECIES OF MARINE RED-TIDE MICROALGAE Influence of Ultraviolet B Radiation on the Phenylpropanoid Metabolism in Common Buckwheat (Fagopyrum esculentum Moench) PLANT RESPONSES TO ATMOSPHERE OZONE DEPLETION,ULTRAVIOLET-B RADIATION INCREASE REACHING THE EARTH‘S SURFACE