摘要
水分胁迫使小麦Triticum aestivum L.叶片光合放氧速率下降,表现为降低叶绿体电子传递速率,且PS Ⅱ电子传递较PS Ⅰ对水分胁迫更为敏感,并表现出明显的解偶联效应;降低叶绿体偶联因子及光合磷酸化活力,使ATP合成受阻。解偶联效应可能与叶绿体光下质子转移受抑有关。
Water stress inhibited the photosynthetic O_2 evolution rate of wheat leaves.It was shown that water stress decreased the electron transport rate,the activities of photophosphorylation and,coupling factor,and,the synthesis of ATP in chloroplasts.PS Ⅱ electron transport was more senstitive to water stress than PS I.The reduction in photophosphorylation activity might be the results of reduction in electron transport rate and coupling factor activity,as well as the uncoupling effect of water stress on chloroplasts.The uncoupling effect could be due to the inhibition of light induced proton translocation in chloroplasts.
关键词
水分胁迫
叶绿体
能量转换
Water stress
Chloroplasts
Photophosphorylation
Energy transduction
Proton transloction
