【作者】 张云华；

【导师】 王荣富；

【作者基本信息】 安徽农业大学 ， 生物物理学， 2003， 硕士

【摘要】 以超级杂交稻两优培九（培矮64S／9311）和母本培矮64S（PA64S）以及父本中籼9311为材料，测定亲本和后代在自然条件下和光氧化条件下叶绿素荧光参数和活性氧代谢的关键指标。同时对¹⁴CO₂同化产物分配和C₄途径酶等指标进行了测定。研究结果表明： 在强光高温下，两优培九的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，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。通过对两优培九及其亲本的比较发现，两优培九的耐光抑制特性偏母本超父本。 光氧化处理后，与父母本相比，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）的降低和非光化学猝灭系数（qN）增加较少，说明在光氧化条件下，超级杂交稻两优培九吸收的光能能较多的转化为化学能，通过热耗散的能量较少；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）诱导的活性高，从而能有效清除叶片内的活性氧，膜脂过氧化较轻。杂交稻两优培九表现耐光抑制／光氧化特性。同时也可以看出超级杂交稻两优培九在耐光氧化特性上具有超双亲的光合生理优势。 在叶片衰老过程中，两优培九的叶绿素、蛋白质含量、PSⅡ的光能利用率（Fv／Fm，qP和φPSⅡ）下降相对较少，而非光化学猝灭系数（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。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。两优培九与其亲本的比较发现：在生育后期衰老过程中杂交稻两优培九抗早衰特性具有偏母本超父本的现象。 用同位素¹⁴C对光合同化产物运转分配进行研究，发现两优培九光合同化产物向穗部的分配比率较高，表明其具有较好的源库协调性。从灌浆前、中、后期标记的¹⁴CO₂同化产物在穗上部和下部的分配比例来看，两优培九较父本9311上部穗的强势粒多，满足灌浆时间较长。这可能是其高产的一个机理。 通过对超级杂交稻两优培九及其亲本叶片中与C₄途径有关的酶的含量测定，我们发现：两优培九的C₄循环中CO₂固定的关键酶PEPcase，NADP-ME，NAD-ME和PPDK的活性均表现出超双亲的优势。这可能是其耐光抑制的一个生理基础。 综上所述，两优培九的高产与其耐光抑制/光氧化，抗早衰和良好的源库协调性以及高活性的C;途径酶有关。此研究为超高产稻的选育提供了必要的生理生化依据。更多还原

【Abstract】 Based on the data collected from the super-hybrid rice "Liangyoupeijiu" ( Pei’ai64S/9311) and its female parent Pei’ai64S and its male parent Indica rice 9311, their chlorophyll fluorescence parameters and the key indexes of active oxygen metabolism were measured separately under both natural and photooxidized condition. Meanwhile, the distribution of 14CO2 assimilate products and €4 pathway enzymes were studied as well. The results are stated as follows.Under high temperature of strong light, the decrease of PS II primary photochemical efficiency(Fv/Fm)and photochemical quenching coefficient (qP) were low; and the increment of non-photochemical quenching coefficient (qN) were not evident either. While in the natural condition, light energy absorbed by "Licingyoupeijiu" was mostly converted into chemical energy and little was dissipated in the form of thermal energy, which shows its capability of tolerance for photoinhibition. In the comparison of the filial and its parents, it was observed that the young one has, surpassing its male parent, adopted its female parent’s features of tolerance for photoinhibition .After the process of photooxidization, both the decrement of the contents of chlorophyll and protein and PS II primary photochemical efficiency (Fv/Fm) as well as photochemical quenching coefficient (qP) and the increment of non-photochemical quenching coefficient (qN) in super-hybrid rice "Liangyoupeijiu" were very small, compared with its parents. These suggest that most light energy absorbed by "Liangyoupeijiu" was converted into chemical energy and little was dissipated in the form of thermal energy. Furthermore, the it had a positive inductive activation of scavenging active oxygen enzymes, such as superoxide dismutase (SOD) and peroxidase (POD), which in turn helped to clear up endogenous active oxygen could be scavenged efficiently and thus limited the membrane-lipid peroxidation. As a result, it was demonstrated that "Liangyoupeijiu" had outgrown its parents in photosynthetic physiology and possessed the advantage of tolerance for photooxidation .In its leaf aging process, the decrement of its contents of chlorophyll and protein and PS II light energy (Fv/Fm, qP and PS II ) were relatively small, while the increment of non-photochemical quenching coefficient (qN) were not obvious either. That again suggeststhe fact that most light energy absorbed by "Liangyoupeijiu" was converted into chemical energy and little was dissipated in the form of thermal energy. Besides, for its inductive activity of scavenging active oxygen enzymes such as superoxide dismutase (SOD) and peroxidase (POD) were high, it had a strong tolerance for photoinhibition and early aging. With the comparison of its parents, it had the characteristics of resistant to early aging in its late process of reproduction, which seemed to have adopted from its female parent other than form its male one.14C was applied studied on the distribution and transportation of photosynthesis assimilate products in "Liangyoupeijhr and it was found out that they were mainly distributed in its panicle other than any other parts, which meant it had a better coordination of source-sink. Measured separately at the early, late and between stages of its milk time, the distribution percentage labeled at upper and lower parts of panicle showed that "Liangyoitpeijiu" had far more potential strong grains in the upper than its male parent 9311 and that it had a longer milk time. This is perhaps one of the possible reasons for its super high yielding.Last but not least, stronger activations of key enzymes, fixed by CO2 , in €4 pathway, such as PEPcase, NADP-ME, NAD-ME and PPDK, were demonstrated in "Liangyoupeijiu". This was speculated as one of its physiological reasons for its tolerant for photoinhibition.As a conclusion, the high yielding of "Liangyoiipeijiu" owed a lot to its tolerance for photoinhibition/photooxidation, its resistance to early aging and its capacity of well-coordination of source-sink as well as its activation of €4 pat更多还原