超级杂交稻两优培九及其亲本生育后期的光抑制和早衰特性

Characteristics of Photoinhibition and Early Aging in Super-hybrid Rice (Oryza sativa L.) "Liangyoupeijiu" and It's Parents at Late Development Stage

以超级杂交稻两优培九 (培矮 6 4S 931 1 )和母本培矮 6 4S(PA6 4S)以及父本中籼 931 1为材料 ,研究亲本和后代在自然条件下叶绿素荧光和活性氧代谢的差异。结果表明 :强光高温下 ,在叶片衰老过程中 ,两优培九的叶绿素、蛋白质含量、PSⅡ原初光化学效率 (Fv Fm)和光化学猝灭系数 (qP)减少较少 ,非光化学猝灭系数 (qN)增加不明显 ,说明在自然条件下 ,超级杂交稻两优培九吸收的光能较多地转化为化学能 ,热耗散较少 ,耐光抑制。同时两优培九的内源活性氧清除酶系如超氧化物歧化酶 (SOD)和过氧化物酶 (POD)诱导的活性较高 ,表现耐光氧化和抗早衰。

With the materials of super hybrid rice 'Liangyoupeijiu' and its female parent Peiai64S and male parent indica rice 9311, relationships between Liangyoupeijiu and it's parents were studied through chlorophyll fluorescence parameters and key indexes of active oxygen metabolism under natural condition The decrease of contents of chlorophyll and protein, PSⅡprimary photochemical efficiency( F v/ F m)and photochemical quenching coefficient ( q P) were less; increment of non photochemical quenching coefficient( q N)were less in super hybrid rice Liangyoupeijiu at noon (high light intensity and temperature) and during leaf senescence The above results suggested that more light energy absorbed by Liangyoupeijiu was converted into chemical energy and less light energy was dissipated through thermal energy, showing the tolerance to photoinhibition Meantime, the inductive activity of scavenging active oxygen enzymes such as superoxide dismutase (SOD) and peroxidase (POD) were higher Thus endogenous active oxygen could be scavenged efficiently As a result, the membrane lipid peroxidation was lighter These showed the tolerance to photooxidation and resistant to early aging The above results demonstrated that super hybrid rice 'Liangyoupeijiu' had photosynthetic physiology advantage in the tolerance to photoinhibition and resistant to early aging