Effects Of Different Nitrogen Fertilizer Applied Ratio On Yield And Quality Of Wheat

The thesis studies the regulation effects of nitrogen application on yield and quality of two wheat varieties, Yannong19and Lankao aizao8on the basis of the experiment conducted at field. The result indicates that:Frist, Effects of nitrogen application on the stalk lodging of the different spike type wheatThe second outside stem, the depth of skin and the growth of each branch is closely related with the stalk lodging. The second outside stem, the depth of skin, the strength and the growth of each branch of two wheat varieties decrease with the growth of nitrogen application, and increase in number and depth with the delayed application of nitrogen.By comparison with the state of branches of the LAI of Yannong19and the SPAD value of Lankao aizao8, it can be concluded that the second outside stem, the depth of skin, the strength and the growth of each branch are higher those of Yannongl9. Therefore, the ratio of anti-stalk lodging of Lankao aizao8is better than that of Yannongl9, which shows that the capability of anti-stalk lodging of big spike-type varieties is better than that of various spike-type varieties.Second, Effects of nitrogen application on aging of wheat flag leaf.Comparing to big-spike wheat varieties, Yannong19, a multi-spike wheat variety, holds a higher SOD enzyme activity in20days after blossoming. However,25days after blossoming, the SOD enzyme activity of Yannong19decreases faster than that of Lankaoaizao8, a big-spike wheat variety. Under the same treatment condition, the MDA proportion of Lankaoaizao8is smaller than that of Yannong19, but big-spike wheat varieties age more slowly than multi-spike wheat varieties. With the same amount of nitrogen fertilizer applied, for the two wheat varieties, the SOD enzyme activity increases and the MDA proportion tends to decline with the growth of topdressing. Under the same Nitrogen fertilizer applied ratio, with the rising of Nitrogen fertilizer, the SOD enzyme activity and the MDA proportion of flag leaves have the tendency of increase and decrease respectively.Third,Effects of nitrogen application proportion on Photosynesis ability of different wheat variety with different type spikeFrom the wintering period to the jointing period, the SPAD value of2varieties both increased with a higher basal ratio of nitrogen application. N basal application could effectively regulate the flagleaf photosynthesis capability of both varieties. For Yannong19, The photosynthesis was higher for the upper three leaves when the ratio of base and top-dressing nitrogen fertilizer was5:5.Fourth, Effects of nitrogen application on Photosynesis capability of different wheat varietiesPhotosythesis is an extremely important process for plants’metabolism. The change of photosynthesis makes a significant effect on plants’growth, output and anti-adversity. So, we can regard photosynthesis as a standard of judging the growth of plants and the strength of anti-adversity. Studies show:with the growth of nitrogen, there is an increasing of wheat’s SPAD value as well as its photosynthetic rate in some range of nitrogen fertilizer rate. However, the excessive (300kg hm-2) or lack(150kg hm-2) of nitrogen fertilizer will both decrease the photosynthesis’standard of wheat’s blades and the output. Therefore, increasing the rate of nitrogen fertilizer can make wheat’s photosynthesis, the weight of its particles and its output better. The use of nitrogenous fertilizer’s postpone technique can make a decreasing of average filling rate, a long time of duration of filling. At the later period of filling, the filling rate will relatively slow down, while belong the time of filling.During the whole growth period of Yannongl9, its chlorophyll content always changes in a single peak. From the wintering period to the jointing period, there is an increasing of its chlorophyll content. It is at the largest when it is at the jointing period, and then it will go down gradually. Within different standards of nitrogen fertilizer, the chlorophyll content of flagleaf will enlarge with using nitrogenous fertilizer’s postpone technique. For Lankao Aizao8wheat:from the wintering period to the jointing period, its chlorophyll content tends to enlarge. Then, from the jointing period to the heading period, its chlorophyll content tends to stable. At the later period of the growth,4:6ratio of base and top-dressing nitrogen fertilizer is smaller, and higher chlorophyll content.Fifth, Effects of nitrogen application on energy transfer and production of different wheat varietiesWithin different standards of nitrogen fertilizer, with the improvement of nitrogenous fertilizer’s postpone technique, the transfer ratio and the contribution rate of the plants will both slow down. At the same time, the green organs of the relative flowers will make a progress of the contribution rat of its output. For Yannong19wheat, the ratio of base nitrogen fertilizer is4:6, the ratio of middle and high nitrogen fertilizer is5:5, and it is at the highest output when it reaches7:3. The contribution rate of vegetative organs before blooming flowers to ketnel sink of the large spike-type is smaller than that of multi-spike type wheat. For large spike-type, we should pay more attention to the usage of base fertilizer; make sure the nutrition-supply of wheat’s tillering stage, improve the wheat’s tillering numbers and make the proportion of tillering effect and increase the spike number of the wheat. At last, there is a high production group. Before making sure the nutrition-supplied enough, it is need to use nitrogenous fertilizer’s postpone technique, keep a high group quality in wheat’s filling period, belong the time of wheat’s filling and to prevent its premature senility.