Impacts of ultraviolet irradiation on the sperm motility and longevity of Acipenser baerii. EFFECTS OF THREE IRRADIATION METHODS ON POLLEN GERMINATION AND POLLEN TUBE GROWTH OF Pinus thunbegii ULTRASTRUCTURE OF CELL WALLS AND COLOUR CHANGE IN PHYLLOSTACHYS PUBESCENS CULM AFTER THE TREATMENT OF ULTRAVIOLET IRRADIATION Effects of UV-B Treatment on the Major Quality of Blueberry and Related Enzyme Activities in Different Developmental Stages