Effects Of Two Fertilizer Reducing Pathways On Maize Fertilization

As an important nitrogen supplement,nitrogen fertilizer plays an important role in increasing maize yield.In pursuit of high yield of maize,the amount of nitrogen fertilizer is more and more big,and the high nitrogen application rate has caused serious environmental problems.According to the maize planting area maize cultivation in the downstream nitrogen fertilizer nitrogen application process is unreasonable,low utilization rate,high residual nitrogen problem.In order to further reduce the amount of nitrogen fertilizer,improve the utilization rate and reduce the residual nitrate,we designed a two-year experiment in this area,through two different ways to reduce fertilizer(Reduction of nitrogen in maize based on soil fertilization?Fertilizer reduction based on fertilizer dosage)The effects of different nitrogen reduction rates on maize yield,above ground biomass,nitrogen use efficiency and residual nitrate nitrogen in soil were studied.While ensuring that the crop is not cut at the same time,reduce the amount of fertilizer applied to explore the best amount of fertilizer for the scientific and rational application of chemical fertilizers to provide a theoretical basis.The main results are as follows:1.The plant height of maize in the whole growth period continued to increase to a steady trend,while the stem diameter increased first and then decreased to a steady trend.In the experiment of nitrogen fertilizer reduction,the plant height and stem diameter of the plant increased significantly with the increase of nitrogen application rate.When the amount of fertilizer reached 160kg/hm~2,the excessive fertilization had no significant effect on plant height and stem diameter.In the treatment of gravel,the gravel was more suitable for the growth and development of maize plants.Compared with FFP,there was no significant difference in FFP treatment when the tillage was reduced by 25%.2.Fertilization can significantly increase maize grain yield.In the nitrogen fertilizer reduction test,maize yield was not significantly reduced with nitrogen fertilizer amount reducing by 20% at Fulongquan and Mishazi test site and 30% at Kaian test site.The highest yield was obtained in the 10% reduction of nitrogen at Fulongquan and Kaian site.In the same fertilization treatment,the application of gravel fertilizer can significantly increase the grain yield of corn.When the tillage is reduced by 25%,the grain yield of maize is not significantly decreased.3.The dry matter accumulation in maize increased with the increase of nitrogen application rate.In the experiment of nitrogen fertilizer reduction,the dry matter accumulation of N258 treated with N-10 and N-10 dry matter accumulation was not significantly different,but significantly higher than N-30 and N-40 treatment.In the gravel test,the amount of gravel fertilizer reduced to 170kg/hm~2 level showed a significant reduction.Indicating that the appropriate reduction in fertilizer inputs will not have a greater impact on the dry matter accumulation of maize.4.In the nitrogen fertilizer reduction test,Higher nitrogen recovery efficiency was obtained by reducing 10%~30% nitrogen fertilizer applications,nitrogen agronomic efficiency was highest when nitrogen fertilizer was reduced by 10%.In the gravel test,the nitrogen use efficiency of the fertilizer application was significantly higher than that of the FFP treatment.And the nitrogen use rate increased with the decrease of nitrogen fertilizer application rate.The utilization rate of nitrogen fertilizer in gravel fertilizer was 36.8~73.6% higher than that of FFP.When the tillage treatment is reduced by 25%,the agronomic efficiency of nitrogen fertilizer is the highest.5.The residue of nitrate was increased by nitrogen application in soil after maize harvest.Nitrate nitrogen residue in 0~18cm soil layer was decreased significantly when nitrogen fertilizer was reduced by 30%,and in 18~40cm soil layer was decreased significantly when reduce the amount of 20% nitrogen fertilizer.The results of this research indicated that when the nitrogen application was 185 kg/hm~2~243 kg/hm~2,soil nitrate nitrogen concentration after harvesting was almost equivalent to the content before planting.In summary,in 2015 the Yinma River downstream region corn reducing nitrogen fertilizer experiment,the amount of nitrogen fertilizer can be reduced by 20~30%,that was 185 kg/hm~2~206 kg/hm~2.Corn grain yield can be maintained and the nitrogen use efficiency can be improved,and soil nitrate nitrogen concentration after harvesting was almost equivalent to the content before planting..In the 2016 reduction test of gravel fertilizer,the fertilizer can be reduced by 20~30%,that was 170 kg/hm~2.Corn grain yield can be maintained and the nitrogen use efficiency can be improved.Comprehensive maize yield,nitrogen efficiency and nitrogen changes and other factors,Yinma River downstream region of Spring Maize in the best way for less nitrogen fertilizer gravel,the optimum nitrogen application amount was 170kg/hm~2.