【摘要】 以高产杂交稻两优培九和常规杂交稻汕优63为材料,研究10℃夜间低温处理对水稻幼苗叶绿体自发荧光强度及抗氧化系统的影响。与同时期的常温对照相比,两优培九的SOD、GR、CAT、POD酶活性的上升幅度要强于汕优63,而汕优63的GSH、ASA含量的上升幅度要强于两优培九。两优培九的O2-和MDA的积累少,叶绿体自发荧光强度降低程度小于汕优63。表明两优培九幼苗的抗冷性优于汕优63。胁迫后期,两优培九中一些保护酶类活性低于对照,O2-产生速率和MDA含量高于对照,表明此时活性氧清除系统的平衡已被破坏。更多还原

【Abstract】 To clarify the resistance of high-yield hybrid rice （Oryza sativa L） at seedling stage to chilling temperature,antioxidant system and chloroplast auto-fluorescence were investigated in two cultivars-Liangyoupeijiu and Shanyou63,setting 25℃ as control and 10℃ as low temperature treatment.The results indicated that under low temperature,the increasing extent of the activity of superoxide dismutase and glutathione reductase was higher in Liangyoupeijiu than that in Shanyou63.The activity of catalase in Liangyoupeijiu increased,while that in Shanyou63 decreased.Isoenzyme of peroxidase had evident new expression in Liangyoupeijiu,which was not obvious in Shanyou63.All the above showed that the protective enzyme system of Liangyoupeijiu was superior to that of Shanyou63.Ascorbic acid and glutathione cooperated with each other to clean peroxid.The increasing extent of the content of Ascorbic acid and glutathione were higher in Shanyou63 than in Liangyoupeijiu,which meant the protective nonenzyme system of Liangyoupeijiu was weaker than that of Shanyou63.The producing velocity of O₂^-was lower in Liangyoupeijiu in chilling situation than the normal.But the case was opposite in Shanyou63.The decreasing extent of chloroplast auto-fluorescence was lower in Liangyoupeijiu than that of Shanyou63.The findings indicated that the cold-resistance ability of super-high-yield hybrid rice Liangyoupeijiu was better than the traditional rice cultivar Shanyou63.But at the later period of chilling stress,O₂^-producing velocity and MDA content in Liangyoupeijiu was higher than the normal.This showed that the balance of the clean system of O₂^-had been destroyed.更多还原