Effects Of Nitrogen Regulation On Photosynthetic Characteristics Of Non-leaf Organs Of Spring Wheat After Anthesis

To understand the regulation of nitrogen fertilizer makes the role of photosynthesis on non-leaf organs of spring wheat (the flag leaf sheath, peduncle,glumes) and the relationship between photosynthetic characteristics and yield, wheat cultivar was wheat-Nongmai2 in this study, the research was carried out in Horticultural Research Institute of Inner Mongolia in 2009, there were two experimental designs that including nitrogen fertilizer and nitrogen stage. The study examines that different fertilizer treatments make effect on photosynthetic rate, chlorophyll content, fluorescence characteristics of non-leaf organs of spring wheat, and reaches the following conclusions:1. The results of nitrogen fertilizer show that increasing nitrogen fertilizer can significantly improve the photosynthetic rate, stomata conductance, transpiration rate, reduc intercellular CO2 concentration of the flag leaf sheath, peduncle and glumes on spring wheat after anthesis, and the effect is more significant under N150 fertilization, of which the photosynthetic rate increases by 88.6%, 81.2%, 59.8% than the N0, followed by the N225 fertilization, and all were significantly different level with N0; also increases chlorophyll content and maximal photochemical efficiency of PSâ…¡(Fv/Fm) and the potential activity of PSâ…¡(Fv/Fo) of the non-leaf organs; and there are some differences on photosynthetic characteristics of non-leaf organs among different nitrogen fertilizers.2. The results of nitrogen stage show that nitrogen can significantly improve the photosynthetic rate, stomata conductance, transpiration rate, and can reduce the intercellular CO2 concentration on flag leaf sheath, peduncle, glumes of the non-leaf organs of spring wheat after anthesis at the jointing stage, the photosynthetic rate respectively increases by 12.3%, 16.0%, 5.4% than booting, and increases by 27.6%, 37.5%, 52.6% than heading; the same time to increase the maximum photochemical efficiency of PSâ…¡(Fv/Fm) and the potential activity of PSâ…¡(Fv/Fo), its influence is better than booting and heading in nitrogen; and chlorophyll content was the lowest performance in nitrogen at jointing stage.3. In study on the diurnal dynamics of the non-leaf organs, we found that non-leaf organs were no obvious depression at midday, and photosynthetic rate is higher in the afternoon than the whole morning, which are similar in nitrogen fertilizer and nitrogen fertilizer application during the trial performance, indicating that when the photosynthetic ability of the leaf break down in the lunch state and the non-leaf organs can continue to maintain strong and effective photosynthetic capacity, assimilate more photosynthate.4. The correlation between photosynthetic characteristics of organs non-leaf and production show that amount of nitrogen fertilizer and nitrogen stage at jointing stage can increase the correlation between the photosynthetic rate, chlorophyll content, fluorescence characteristics of non-leaf organs and yield.