The Influence Of Nitrogen Levels On Different Nitrogen Efficiency Maize Varieties Of Accumulation And Yield Components

Nitrogen fertilizer application can promote the photosynthesis, dry matter accumulation.and there is a significant difference of nitrogen absorption and utilization between different corn varieties,the same variety are also different on the absorption utilization of nitrogen under different nitrogen levels.In the actual production,too much nitrogen fertilizer will not only cause the waste of fertilizer, but more easy to pollute the environment.Therefore,the amount of nitrogen fertilizer should be appropriate,and analysis of the relationship between material production, yield components and yield of different nitrogen efficient varieties, especially to find out the appropriate fertilizer levels of each type,can provide certain theoretical basis for high-efficient and high-yield in corn cultivation.In this article,we selected the high nitrogen efficient varieties ZhengHong 311 and the low nitrogen efficient varieties XianYu 508 as test material to test the change rules of the the photo synthetic characteristics,accumulation of dry matter,nitrogen efficiency and production of two maize varieties under six different nitrogen levels,and draw the following conclusions:(1) The impact on the photosynthetic characteristics of those two tested varieties includes photosynthetic area,stomatal conductance of leaves,intercellular CO2 concentration of leaves,transpiration rate,etc.On the whole,the leaf area and photosynthetic rate at spinning tasseling stage of ZhengHong 311 both first increased and then decreased with the increase of nitrogen level,the highest of which was at 360kg/ha.But,those of XianYu 508 increased with the increase of nitrogen level to be the highest at 450kg/ha.(2) Reasonable application of nitrogen fertilizer could increase the dry matter accumulation of these two varieties.No matter it was before or after spinning tasseling stage,the dry matter accumulation of XianYu 508 always increased with the increased of the nitrogen level to the highest at450kg/ha,but ZhengHong 311 first increased and then decreased with the increase of nitrogen level to the highest between 270-360kg/ha.(3) The influence of nitrogen levels on nitrogen absorption and utilization efficiency is significant.In general,with the increase of fertilization levels,the absorption and accumulation of nitrogen increased,but the absorption rate,utilization rate,partial factor productivity and physiological efficiency all decreased.Compared with XianYu 508,the nitrogen absorption rate of ZhengHong 311 was higher,especially at the middle and low nitrogen levels,which made clear that ZhengHong 311 is a high efficiency of nitrogen absorption variety.The nitrogen partial productivity and agronomic efficiency of ZhengHong 311 were also higher than XianYu 508,especially at the middle and low nitrogen levels,but the difference between these two targets was narrow and even going to be the phenomenon that ZhengHong 311 was lower than XianYu 508 at the high nitrogen levels.There were no significant differences between the two varieties of nitrogen physiological efficiency.The nitrogen digestibility of ZhengHong 311 was lower than XianYu 508,which was because of that the nitrogen uptake and accumulation of ZhengHong 311 was higher while there was no fertilizer.(4) The nitrogen fertilizer impacts the root system of these tested maize varieties on the absorption and utilization of nitrogen and the leaves on photosynthesis,which influences the yield of maize.thereupon then which also impacts its economic benefits,but there were not the same to these two tested varieties on the influence extent and trend.In the experimental disposing range,the grain yield and net income of ZhengHong 311 all increased first and then decreased with the increase of nitrogen levels,but which of XianYu 508 increased all the time.The appropriate nitrogen level for high yield and high efficiency of ZhengHong 311 was at the level of 270kg/ha,which of XianYu 508 was at the level of 450kg/ha,which made it clear that ZhengHong 311 was comparatively barren tolerance but XianYu 508 was fertilizer tolerance.