转PEPC基因水稻的光保护效应的可逆动态变化

研究了转PEPC基因水稻及其原种粳稻Kitaake旗叶的叶绿素荧光参数和活性氧代谢有关指标的日变化进程。结果表明,玉米PEPC基因导入水稻后,在高光强下光合速率提高50%,光合作用的光抑制减轻。用PEPC的专一抑制剂证明光合增加确与PEPC基因的导入有关。不同基因型水稻在高光高温自然条件下中午均有光抑制现象,其中转PEPC基因水稻中午Fv/Fm降低较少,光抑制较轻,光能转化为化学能的效率较高,热耗散较低。这些结果为进一步研究转PEPC基因水稻耐光抑制机理和高光效育种提供了依据。

Study of the Protective Effects in PEPC Transgenic Rice

The diurnal course of chlorophyll fluorescence parameter and active oxygen metabolism of flag leaf in PEPC transgenic and untransformed rice Kitaake were studied. The results showed that the photosynthetic rate under high light intensity increased by 50% and photoinhibition of photosynthesis alleviated after the introduction of PEPC gene from maize into rice. It was demonstrated that the increment of photosynthesis was related to the introduction of PEPC gene. Photoinhibition of photosynthesis existed at noon in different genotypes under natural condition with high light and high temperature,in which Fv/Fm reduced less in PEPC transgenic rice, thus photo-inhibition exhibited slightly; The efficiency of light energy transferring to chemical energy was higher; The thermal energy dissipation was lower. These results provided the physiological basis on the mechanism of tolerance to photo-inhibition and rice breeding with high photosynthetic efficiency.