The Relationship Of Nitrogen Application And The Key Photosynthetic Enzyme Activity Of Photosynthetic Organs Of The Spring Wheat

The wheat is one of the important grain crops in China, It is important to reveal the mechanism of photosynthetic to improve the photosynthetic efficiency and increase yield. There are C3 and C4 cycle in the wheat cycle system and the key enzyme activity affects the first step reactions directly in photosynthetic carbon cycle. In order to explore the connection between nitrogen and the total N content of organs and the key photosynthetic enzyme activity, and understand the relationship of the key photosynthetic enzyme activity and the yield. In this experiment, the key photosynthetic enzyme activity of photosynthetic organs were measured under different nitrogen levels. The data was analyzed by correlation analysis and ANOVA analysis. The results showed that: the key photosynthetic enzyme activity of photosynthetic organs changed as a single peak curve after flowering in different treatments, along with the sampling period. It was found that the key photosynthetic enzyme activity exhibit a negative correlation with the total N content decline rate(r =-0.123~ -0.997),whereas the ratio of PEPCase/RuBPCase exhibited a positive correlation with the total N content decline rate(r =0.679~0.993). The PEPCase activity of flag leaf increased in the early grain filling stage with later topdressing nitrogen, the PEPCase activity of flag leaf, glume, and awn was opposite in the later grain filling stage. But later topdressing nitrogen was favor of Peduncle all the time. The RuBPCase activity of organs increased then decreased with amount of applied nitrogen, and reached its maximum at 150~225kg/hm2.The PEPCase activity of non-leaf organs was always higher than that of flag leaf, and the trend increased with amount of applied nitrogen. The PEPCase and the RuBPCase activity of organs exhibited a positive correlation with the wheat yield.