The Effects of Increased UV-B Radiation,NaCl Stress and Their Combined Treatment on the Photosynthesis and Flavone Metabolism in Wheat Seedlings
增强UV-B辐射、NaCl胁迫及其复合处理对小麦幼苗光合作用及黄酮代谢的影响

During increased UV-B radiation,NaCl strees and their combined treatment,measuring the net photosynthetic rate,stomatal conductance,intercellular CO_2 concentration,PAL activity,the contents of chlorophyll and flavone of first leave of wheat seedlings respectively.The net photosynthetic rate,stomatal conductance and intercellular CO_2 concentration of wheat seedlings were reduced by NaCl stress and increased UV-B radiation;In comparison with NaCl stress,NaCl + UV-B did not influence the net photosynthetic rate,stomatal conductance and intercellular CO_2 concentration of wheat seedlings; PAL activity and content of flavone of wheat seedlings were enhanced by increased UV-B radiation,NaCl stress and their combined treatment.The main reason of inhibition of photosynthesis by increased UV-B radiation was stomatal limitation;In NaCl + UV-B treatment,the reduction effect of increased UV-B radiation on photosynthesis of wheat seedlings could be weakened by NaCl stress.