Analysis Of Photosynthesis Specificity Of Transgenic Poplars With PEPC Gene

Poplar plantation area has reached 7 million hm2 in China, leading the world's first .Using genetic engineering of poplar cultivation of new varieties with high photosynthetic efficiency of poplar plantations is important to increase the yield in China. In this study, Transgenic poplar with PEPC gene for materials with the control transgenic plants (non-transgenic poplar) in the seedling growth, Carried out a physiological analysis of transgenic plants, transgenic poplar leaves photosynthetic enzyme activity in transgenic poplar, the process of plant photosynthesis and other aspects of the protective enzyme research, and photosynthesis relevant parameters of a preliminary comparative analysis of high efficiency for selection of transgenic poplar provide the basis for new varieties. The main findings are as follows:(1)After Seedlings were observed analysis showed that, the seedling growth of transgenic poplars was better than the control. Height of transgenic poplars was higher than the control such as PE68, PE33, PE30, PE28, PE84 and other plant were higher than the control, The highest compared with the control by up to 21.5cm; But analysis showed that the strains the contents of chlorophyll varied small.(2) PEPCase is a C4 plant CO₂ assimilation pathway key enzymes, the study showed: PEPC activity increased significantly as high as 22.3%.(3) After determination of photosynthesis-related parameters, and C4 plants PEPC gene transfer combined characteristics of anoplophora analysis shows that: Transgenic poplars have strong capacity for using high light intensity ,and its light saturation point increased than the control by about 10% to 15%.The photosynthetic rates of transgenic poplars in light saturation point were higher than that of the control ,and the light compensation points of transgenic poplars were lower than that of control, and the light compensation points of transgenic poplars were lower than that of control. Also, the ability of transgenic poplars to use low light was stronger than the control.(4)CO₂ saturation point and CO₂ compensation point of transgenic poplars were lower than the control. The photorespiration of transgenic poplars was lower than that of control, which is favorable to photosynthetic formation and organics accumulation. In addition, the transgenic poplars had higher efficiency of carboxylation, the highest of which was higher than that of the control by 62.3%, indicating that transgenic poplars have the ability to use more CO₂.(5) Under photosynthesis, antioxidant enzymes activity in the transgenic poplars were higher that of control. It showed that the transgenic poplars enhanced tolerance to photo oxidation.