D,L-甘油醛处理引起的小麦叶片表观光合量子效率的降低

摘要

Application of D, L-glyceraldehyde ( DL-GA, 10 mmol/L) , an inhibitor of phosphoribulokinase, decreased both net photosynthetic rate and apparent quantum yield of CO2 assimilation (Фc ) by about 20% -30% in winter wheat flag leaves. It also decreased the photochemical efficiency (△F/Fm′) of PS Ⅱ under actinic light, electron transport ratern(ETR) and ATP content per unit leaf area but increased the intercellular CO2 concentration and nonphotochemical quenching of chlorophyll fluorescence (NPQ). These results indicate that after DLGA treatment the decline in apparent quantum yield in wheat flag leaves is due to the feedback inhibition of photornsynthetic electron transport caused by restriction of carbon assimilation.%D,L-甘油醛(磷酸核酮糖激酶抑制剂,10mmol/L)处理小麦旗叶1 h可降低叶片净光合速率和表观量子效率.同时,光系统Ⅱ光化学效率(△F/Fm′)、电子传递速率(ETR)和单位叶面积ATP含量均降低,而胞间二氧化碳浓度(Ci)和叶绿素荧光非光化学猝灭(NPQ)增加.这些结果说明,D,L-甘油醛引起的小麦旗叶表观量子效率降低是由于光合碳同化受阻对光合电子传递的反馈抑制.